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Archive for the ‘Human Immune System in Health and in Disease’ Category

Covid-19 and its implications on pregnancy

Reporter and Curator: Mr. Srinjoy Chakraborty (Junior Research Felllow) and Dr. Sudipta Saha, Ph.D.

Coronavirus disease 2019 (COVID-19), which is caused by the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has emerged as a serious global health issue with high transmission rates affecting millions of people worldwide. The SARS-CoV-2 is known to damage cells in the respiratory system, thus causing viral pneumonia. The novel SARS-CoV-2 is a close relative to the previously identified severe acute respiratory syndrome-coronavirus (SARS-CoV) and Middle East respiratory syndrome-coronavirus (MERS-CoV) which affected several people in 2002 and 2012, respectively. Ever since the outbreak of covid-19, several reports have poured in about the impact of Covid-19 on pregnancy. A few studies have highlighted the impact of the viral infection in pregnant women and how they are more susceptible to the infection because of the various physiological changes of the cardiopulmonary and immune systems during pregnancy. It is known that SARS-CoV and MERS-CoV diseases have influenced the fatality rate among pregnant women. However, there are limited studies on the impact of the novel corona virus on the course and outcome of pregnancy.

Figure: commonly observed clinical symptoms of COVID-19 in the general population: Fever and cough, along with dyspnoea, diarrhoea, and malaise are the most commonly observed symptoms in pregnant women, which is similar to that observed in the normal population.

The WHO and the Indian Council of Medical Research (ICMR) have proposed detailed guidelines for treating pregnant women; these guidelines must be strictly followed by the pregnant individual and their families. According to the guidelines issued by the ICMR, the risk of pregnant women contracting the virus to that of the general population. However, the immune system and the body’s response to a viral infection is altered during pregnancy. This may result in the manifestation of more severe symptoms. The ICMR guidelines also state that the reported cases of COVID-19 pneumonia in pregnancy are milder and with good recovery. However, by observing the trends of the other coronavirus infection (SARS, MERS), the risks to the mother appear to increase in particular during the last trimester of pregnancy. Cases of preterm birth in women with COVID-19 have been mentioned in a few case report, but it is unclear whether the preterm birth was always iatrogenic, or whether some were spontaneous. Pregnant women with heart disease are at highest risk of acquiring the infection, which is similar to that observed in the normal population. Most importantly, the ICMR guidelines highlights the impact of the coronavirus epidemic on the mental health of pregnant women. It mentions that the since the pandemic has begun, there has been an increase in the risk of perinatal anxiety and depression, as well as domestic violence. It is critically important that support for women and families is strengthened as far as possible; that women are asked about mental health at every contact.

With the available literature available on the impact of SARS and MERS on reproductive outcome, it has been mentioned that SARS infection did increase the risk of miscarriage, preterm birth and, intrauterine foetal growth restriction. However, the same has not been demonstrated in early reports from COVID-19 infection in pregnancy. According to a study that included 8200 participants conducted by the centre for disease control and prevention, pregnant women may be at a higher risk of acquiring severe infection and need for ICU admissions as compared to their non-pregnant counterparts. However, a detailed and thorough study involving a larger proportion of the population is needed today.

References:

https://www.news-medical.net/news/20210614/COVID-19-in-pregnancy-could-be-less-severe-than-previously-thought-A-Danish-case-study.aspx

https://obgyn.onlinelibrary.wiley.com/doi/10.1111/jog.14696

https://www.nature.com/articles/s41577-021-00525-y

https://www.tandfonline.com/doi/full/10.1080/14767058.2020.1759541

https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/special-populations/pregnancy-data-on-covid-19/what-cdc-is-doing.html

https://economictimes.indiatimes.com/news/india/why-is-covid-19-killing-so-many-pregnant-women-in-india/articleshow/82902194.cms?from=mdr

https://content.iospress.com/download/international-journal-of-risk-and-safety-in-medicine/jrs200060?id=international-journal-of-risk-and-safety-in-medicine%2Fjrs200060

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Thriving Vaccines and Research: Weizmann Institute Coronavirus Research Development

Reporter: Amandeep Kaur, B.Sc., M.Sc.

In early February, Prof. Eran Segal updated in one of his tweets and mentioned that “We say with caution, the magic has started.”

The article reported that this statement by Prof. Segal was due to decreasing cases of COVID-19, severe infection cases and hospitalization of patients by rapid vaccination process throughout Israel. Prof. Segal emphasizes in another tweet to remain cautious over the country and informed that there is a long way to cover and searching for scientific solutions.

A daylong webinar entitled “COVID-19: The epidemic that rattles the world” was a great initiative by Weizmann Institute to share their scientific knowledge about the infection among the Israeli institutions and scientists. Prof. Gideon Schreiber and Dr. Ron Diskin organized the event with the support of the Weizmann Coronavirus Response Fund and Israel Society for Biochemistry and Molecular Biology. The speakers were invited from the Hebrew University of Jerusalem, Tel-Aviv University, the Israel Institute for Biological Research (IIBR), and Kaplan Medical Center who addressed the molecular structure and infection biology of the virus, treatments and medications for COVID-19, and the positive and negative effect of the pandemic.

The article reported that with the emergence of pandemic, the scientists at Weizmann started more than 60 projects to explore the virus from different range of perspectives. With the help of funds raised by communities worldwide for the Weizmann Coronavirus Response Fund supported scientists and investigators to elucidate the chemistry, physics and biology behind SARS-CoV-2 infection.

Prof. Avi Levy, the coordinator of the Weizmann Institute’s coronavirus research efforts, mentioned “The vaccines are here, and they will drastically reduce infection rates. But the coronavirus can mutate, and there are many similar infectious diseases out there to be dealt with. All of this research is critical to understanding all sorts of viruses and to preempting any future pandemics.”

The following are few important projects with recent updates reported in the article.

Mapping a hijacker’s methods

Dr. Noam Stern-Ginossar studied the virus invading strategies into the healthy cells and hijack the cell’s systems to divide and reproduce. The article reported that viruses take over the genetic translation system and mainly the ribosomes to produce viral proteins. Dr. Noam used a novel approach known as ‘ribosome profiling’ as her research objective and create a map to locate the translational events taking place inside the viral genome, which further maps the full repertoire of viral proteins produced inside the host.

She and her team members grouped together with the Weizmann’s de Botton Institute and researchers at IIBR for Protein Profiling and understanding the hijacking instructions of coronavirus and developing tools for treatment and therapies. Scientists generated a high-resolution map of the coding regions in the SARS-CoV-2 genome using ribosome-profiling techniques, which allowed researchers to quantify the expression of vital zones along the virus genome that regulates the translation of viral proteins. The study published in Nature in January, explains the hijacking process and reported that virus produces more instruction in the form of viral mRNA than the host and thus dominates the translation process of the host cell. Researchers also clarified that it is the misconception that virus forced the host cell to translate its viral mRNA more efficiently than the host’s own translation, rather high level of viral translation instructions causes hijacking. This study provides valuable insights for the development of effective vaccines and drugs against the COVID-19 infection.

Like chutzpah, some things don’t translate

Prof. Igor Ulitsky and his team worked on untranslated region of viral genome. The article reported that “Not all the parts of viral transcript is translated into protein- rather play some important role in protein production and infection which is unknown.” This region may affect the molecular environment of the translated zones. The Ulitsky group researched to characterize that how the genetic sequence of regions that do not translate into proteins directly or indirectly affect the stability and efficiency of the translating sequences.

Initially, scientists created the library of about 6,000 regions of untranslated sequences to further study their functions. In collaboration with Dr. Noam Stern-Ginossar’s lab, the researchers of Ulitsky’s team worked on Nsp1 protein and focused on the mechanism that how such regions affect the Nsp1 protein production which in turn enhances the virulence. The researchers generated a new alternative and more authentic protocol after solving some technical difficulties which included infecting cells with variants from initial library. Within few months, the researchers are expecting to obtain a more detailed map of how the stability of Nsp1 protein production is getting affected by specific sequences of the untranslated regions.

The landscape of elimination

The article reported that the body’s immune system consists of two main factors- HLA (Human Leukocyte antigen) molecules and T cells for identifying and fighting infections. HLA molecules are protein molecules present on the cell surface and bring fragments of peptide to the surface from inside the infected cell. These peptide fragments are recognized and destroyed by the T cells of the immune system. Samuels’ group tried to find out the answer to the question that how does the body’s surveillance system recognizes the appropriate peptide derived from virus and destroy it. They isolated and analyzed the ‘HLA peptidome’- the complete set of peptides bound to the HLA proteins from inside the SARS-CoV-2 infected cells.

After the analysis of infected cells, they found 26 class-I and 36 class-II HLA peptides, which are present in 99% of the population around the world. Two peptides from HLA class-I were commonly present on the cell surface and two other peptides were derived from coronavirus rare proteins- which mean that these specific coronavirus peptides were marked for easy detection. Among the identified peptides, two peptides were novel discoveries and seven others were shown to induce an immune response earlier. These results from the study will help to develop new vaccines against new coronavirus mutation variants.

Gearing up ‘chain terminators’ to battle the coronavirus

Prof. Rotem Sorek and his lab discovered a family of enzymes within bacteria that produce novel antiviral molecules. These small molecules manufactured by bacteria act as ‘chain terminators’ to fight against the virus invading the bacteria. The study published in Nature in January which reported that these molecules cause a chemical reaction that halts the virus’s replication ability. These new molecules are modified derivates of nucleotide which integrates at the molecular level in the virus and obstruct the works.

Prof. Sorek and his group hypothesize that these new particles could serve as a potential antiviral drug based on the mechanism of chain termination utilized in antiviral drugs used recently in the clinical treatments. Yeda Research and Development has certified these small novel molecules to a company for testing its antiviral mechanism against SARS-CoV-2 infection. Such novel discoveries provide evidences that bacterial immune system is a potential repository of many natural antiviral particles.

Resolving borderline diagnoses

Currently, Real-time Polymerase chain reaction (RT-PCR) is the only choice and extensively used for diagnosis of COVID-19 patients around the globe. Beside its benefits, there are problems associated with RT-PCR, false negative and false positive results and its limitation in detecting new mutations in the virus and emerging variants in the population worldwide. Prof. Eran Elinavs’ lab and Prof. Ido Amits’ lab are working collaboratively to develop a massively parallel, next-generation sequencing technique that tests more effectively and precisely as compared to RT-PCR. This technique can characterize the emerging mutations in SARS-CoV-2, co-occurring viral, bacterial and fungal infections and response patterns in human.

The scientists identified viral variants and distinctive host signatures that help to differentiate infected individuals from non-infected individuals and patients with mild symptoms and severe symptoms.

In Hadassah-Hebrew University Medical Center, Profs. Elinav and Amit are performing trails of the pipeline to test the accuracy in borderline cases, where RT-PCR shows ambiguous or incorrect results. For proper diagnosis and patient stratification, researchers calibrated their severity-prediction matrix. Collectively, scientists are putting efforts to develop a reliable system that resolves borderline cases of RT-PCR and identify new virus variants with known and new mutations, and uses data from human host to classify patients who are needed of close observation and extensive treatment from those who have mild complications and can be managed conservatively.

Moon shot consortium refining drug options

The ‘Moon shot’ consortium was launched almost a year ago with an initiative to develop a novel antiviral drug against SARS-CoV-2 and was led by Dr. Nir London of the Department of Chemical and Structural Biology at Weizmann, Prof. Frank von Delft of Oxford University and the UK’s Diamond Light Source synchroton facility.

To advance the series of novel molecules from conception to evidence of antiviral activity, the scientists have gathered support, guidance, expertise and resources from researchers around the world within a year. The article reported that researchers have built an alternative template for drug-discovery, full transparency process, which avoids the hindrance of intellectual property and red tape.

The new molecules discovered by scientists inhibit a protease, a SARS-CoV-2 protein playing important role in virus replication. The team collaborated with the Israel Institute of Biological Research and other several labs across the globe to demonstrate the efficacy of molecules not only in-vitro as well as in analysis against live virus.

Further research is performed including assaying of safety and efficacy of these potential drugs in living models. The first trial on mice has been started in March. Beside this, additional drugs are optimized and nominated for preclinical testing as candidate drug.

Source: https://www.weizmann.ac.il/WeizmannCompass/sections/features/the-vaccines-are-here-and-research-abounds

Other related articles were published in this Open Access Online Scientific Journal, including the following:

Identification of Novel genes in human that fight COVID-19 infection

Reporter: Amandeep Kaur, B.Sc., M.Sc. (ept. 5/2021)

https://pharmaceuticalintelligence.com/2021/04/19/identification-of-novel-genes-in-human-that-fight-covid-19-infection/

Fighting Chaos with Care, community trust, engagement must be cornerstones of pandemic response

Reporter: Amandeep Kaur, B.Sc., M.Sc. (ept. 5/2021)

https://pharmaceuticalintelligence.com/2021/04/13/fighting-chaos-with-care/

T cells recognize recent SARS-CoV-2 variants

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2021/03/30/t-cells-recognize-recent-sars-cov-2-variants/

Need for Global Response to SARS-CoV-2 Viral Variants

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2021/02/12/need-for-global-response-to-sars-cov-2-viral-variants/

Mechanistic link between SARS-CoV-2 infection and increased risk of stroke using 3D printed models and human endothelial cells

Reporter: Adina Hazan, PhD

https://pharmaceuticalintelligence.com/2020/12/28/mechanistic-link-between-sars-cov-2-infection-and-increased-risk-of-stroke-using-3d-printed-models-and-human-endothelial-cells/

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Live Notes and Conference Coverage in Real Time. COVID19 And The Impact on Cancer Patients Town Hall with Leading Oncologists; April 4, 2020

Reporter: Stephen J. Williams, PhD 

@StephenJWillia2

UPDATED 5/11/2020 see below

This update is the video from the COVID-19 Series 4.

UPDATED 4/08/2020 see below

The Second in a Series of Virtual Town Halls with Leading Oncologist on Cancer Patient Care during COVID-19 Pandemic: What you need to know

The second virtual Town Hall with Leading International Oncologist, discussing the impact that the worldwide COVID-19 outbreak has on cancer care and patient care issues will be held this Saturday April 4, 2020.  This Town Hall Series is led by Dr. Roy Herbst and Dr. Hossain Borghaei who will present a panel of experts to discuss issues pertaining to oncology practice as well as addressing physicians and patients concerns surrounding the risk COVID-19 presents to cancer care.  Some speakers on the panel represent oncologist from France and Italy, and will give their views of the situation in these countries.

Speakers include:

Roy S. Herbst, MD, PhD, Ensign Professor of Medicine (Medical Oncology) and Professor of Pharmacology; Chief of Medical Oncology, Yale Cancer Center and Smilow Cancer Hospital; Associate Cancer Center Director for Translational Research, Yale Cancer Center

Hossain Borghaei, DO, MS , Chief of Thoracic Medical Oncology and Director of Lung Cancer Risk Assessment, Fox Chase Cancer Center

Giuseppe Curigliano, MD, PhD, University of Milan and Head of Phase I Division at IEO, European Institute of Oncology

Paolo Ascierto, MD National Tumor Institute Fondazione G. Pascale, Medical oncologist from National Cancer Institute of Naples, Italy

Fabrice Barlesi, MD, PhD, Thoracic oncologist Cofounder Marseille Immunopole Coordinator #ThePioneeRproject, Institut Gustave Roussy

Jack West, MD, Department of Medical Oncology & Therapeutics Research, City of Hope California

Rohit Kumar, MD Department of Medicine, Section of Pulmonary Medicine, Fox Chase Cancer Center

Christopher Manley, MD Director, Interventional Pulmonology Fox Chase Cancer Center

Hope Rugo, MD FASCO Division of Hematology and Oncology, University of California San Francisco (UCSF) Helen Diller Family Comprehensive Cancer Center

Harriet Kluger, MD Professor of Medicine (Medical Oncology); Director, Yale SPORE in Skin Cancer, Yale Cancer Center

Marianne J. Davies, DNP, MSN, RN, APRN, CNS-BC, ACNP-BC, AOCNP Assistant Professor of Nursing, Yale University

Barbara Burtness, MD Professor of Medicine (Medical Oncology);  Head and Neck Cancers Program, Yale University

@pharma_BI and @StephenJWillia2 will be Tweeting out live notes using #CancerCareandCOVID19

Live Notes

Part I: Practice Management

Dr. Jack West from City of Hope talked about telemedicine:  Coordination of the patient experience, which used to be face to face now moved to a telemedicine alternative.  For example a patient doing well on personalized therapy, many patients are well suited for a telemedicine experience.  A benefit for both patient and physician.

Dr. Rohit Kumar: In small cancer hospitals, can be a bit difficult to determine which patient needs to come in and which do not.  For outpatients testing for COVID is becoming very pertinent as these tests need to come back faster than it is currently.  For inpatients the issue is personal protection equipment.  They are starting to reuse masks after sterilization with dry heat.   Best to restructure the system of seeing patients and scheduling procedures.

Dr. Christopher Manley: hypoxia was an issue for COVID19 patients but seeing GI symptoms in 5% of patients.  Nebulizers have potential to aerosolize.  For patients in surgery prep room surgical masks are fine.  Ventilating these patients are a challenge as hypoxia a problem.  Myocarditis is a problem in some patients.  Diffuse encephalopathy and kidney problems are being seen. So Interleukin 6 (IL6) inhibitors are being used to reduce the cytokine storm presented in patients suffering from COVID19.

Dr. Hope Rugo from UCSF: Breast cancer treatment during this pandemic has been challenging, even though they don’t use too much immuno-suppressive drugs.  How we decide on timing of therapy and future visits is crucial.  For early stage breast cancer, neoadjuvant therapy is being used to delay surgeries.  Endocrine therapy is more often being used. In patients that need chemotherapy, they are using growth factor therapy according to current guidelines.  Although that growth factor therapy might antagonize some lung problems, there is less need for multiple visits.

For metastatic breast cancer,  high risk ER positive are receiving endocrine therapy and using telemedicine for followups.  For chemotherapy they are trying to reduce the schedules or frequency it is given. Clinical trials have been put on hold, mostly pharmokinetic studies are hard to carry out unless patients can come in, so as they are limiting patient visits they are putting these type of clinical studies on hold.

Dr. Harriet Kluger:  Melanoma community of oncologists gathered together two weeks ago to discuss guidelines and best practices during this pandemic.   The discussed that there is a lack of data on immunotherapy long term benefit and don’t know the effectiveness of neoadjuvant therapy.  She noted that many patients on BRAF inhibitors like Taflinar (dabrafenib)   or Zelboraf (vemurafenib) might get fevers as a side effect from these inhibitors and telling them to just monitor themselves and get tested if they want. Yale has also instituted a practice that, if a patient tests positive for COVID19, Yale wants 24 hours between the next patient visit to limit spread and decontaminate.

Marianne Davies:  Blood work is now being done at satellite sites to limit number of in person visits to Yale.  Usually they did biopsies to determine resistance to therapy but now relying on liquid biopsies (if insurance isn’t covering it they are working with patient to assist).  For mesothelioma they are dropping chemotherapy that is very immunosuppressive and going with maintenance pembrolizumab (Keytruda).  It is challenging in that COPD mimics the symptoms of COVID and patients are finding it difficult to get nebulizers at the pharmacy because of shortages; these patients that develop COPD are also worried they will not get the respirators they need because of rationing.

Dr. Barbara Burtness: Head and neck cancer.  Dr. Burtness stresses to patients that the survival rate now for HPV positive head and neck is much better and leaves patients with extra information on their individual cancers.  She also noted a registry or database that is being formed to track data on COVID in patients undergoing surgery  and can be found here at https://globalsurg.org/covidsurg/

About CovidSurg

  • There is an urgent need to understand the outcomes of COVID-19 infected patients who undergo surgery.
  • Capturing real-world data and sharing international experience will inform the management of this complex group of patients who undergo surgery throughout the COVID-19 pandemic, improving their clinical care.
  • CovidSurg has been designed by an international collaborating group of surgeons and anesthetists, with representation from Canada, China, Germany, Hong Kong, Italy, Korea, Singapore, Spain, United Kingdom, and the United States.

Dr. Burtness had noted that healthcare care workers are at high risk of COVID exposure during ear nose and throat (ENT) procedures as the coronavirus resides in the upper respiratory tract.  As for therapy for head and neck cancers, they are staying away from high dose cisplatin because of the nephrotoxicity seen with high dose cisplatin.  An alternative is carboplatin which generally you do not see nephrotoxicity as an adverse event (a weekly carboplatin).  Changing or increasing dose schedule (like 6 weeks Keytruda) helps reduce immunologic problems related to immunosupression and patients do not have to come in as often.

Italy and France

Dr. Paolo Ascierto:   with braf inhibitors, using in tablet form so patients can take from home.  Also they are moving chemo schedules for inpatients so longer dosing schedules.  Fever still a side effect from braf inhibitors and they require a swab to be performed to ascertain patient is COVID19 negative.  Also seeing pneumonitis as this is an adverse event from checkpoint inhibitors so looking at CT scans and nasal swab to determine if just side effect of I/O drugs or a COVID19 case.  He mentioned that their area is now doing okay with resources.

Dr. Guiseppe Curigliano mentioned about the redesign of the Italian health system with spokes and hubs of health care.  Spokes are generalized medicine while the hubs represent more specialized centers like CV hubs or cancer hubs.  So for instance, if a melanoma patient in a spoke area with COVID cases they will be referred to a hub.  He says they are doing better in his area

In the question and answer period, Dr. West mentioned that they are relaxing many HIPAA regulations concerning telemedicine.  There is a website on the Centers for Connective Health Policy that shows state by state policy on conducting telemedicine.   On immuno oncology therapy, many in the panel had many questions concerning the long term risk to COVID associated with this type of therapy.  Fabrice mentioned they try to postpone use of I/O and although Dr. Kluger said there was an idea floating around that PD1/PDL1 inhibitors could be used as a prophylactic agent more data was needed.

Please revisit this page as the recording of this Town Hall will be made available next week.

UPDATED 4/08/2020

Below find the LIVE RECORDING and TAKEAWAYS by the speakers

 
Town Hall Takeaways
 

 

Utilize Telehealth to Its Fullest Benefit

 

·       Patients doing well on targeted therapy or routine surveillance are well suited to telemedicine

·       Most patients are amenable to this, as it is more convenient for them and minimizes their exposure

·       A patient can speak to multiple specialists with an ease that was not previously possible

·       CMS has relaxed some rules to accommodate telehealth, though private insurers have not moved as quickly, and the Center for Connected Health Policy maintains a repository of current state-by-state regulations:  https://www.cchpca.org/

 

Practice Management Strategies

 

·       In the face of PPE shortages, N95 masks can be decontaminated using UV light, hydrogen peroxide, or autoclaving with dry heat; the masks can be returned to the original user until the masks are no longer suitable for use

·       For blood work or scans, the use of external satellite facilities should be explored

·       Keep pumps outside of the room so nurses can attend to them quickly

·       Limit the use of nebulizers, CPAPs, and BiPAPs due to risk of aerosolization

 

Pool Our Knowledge for Care of COVID Patients

 

·       There is now a global registry for tracking surgeries in COVID-positive cancer patients:  https://globalsurg.org/cancercovidsurg/

·       Caution is urged in the presence of cardiac complications, as ventilated patients may appear to improve, only to suffer severe myocarditis and cardiac arrest following extubation

·       When the decision is made to intubate, intubate quickly, as less invasive methods result in aerosolization and increased risks to staff

 

Study the Lessons of Europe

 

·       The health care system in Italy has been reorganized into “spokes” and “hubs,” with a number of cancer hubs; if there is a cancer patient in a spoke hospital with many COVID patients, this patient may be referred to a hub hospital

·       Postpone adjuvant treatments whenever possible

·       Oral therapies, which can be managed at home, are preferred over therapies that must be administered in a healthcare setting

·       Pneumonitis patients without fevers may be treated with steroids, but nasal swab testing is needed in the presence of concomitant fever

·       Any staff who are not needed on site should be working from home, and rotating schedules can be used to keep people healthy

·       Devise an annual epidemic control plan now that we have new lessons from COVID

 

We Must Be Advocates for Our Cancer Patients

 

·       Be proactive with other healthcare providers on behalf of patients with a good prognosis

·       Consider writing letters for cancer patients for inclusion into their chart, or addendums on notes, then encourage patients to print these out, or give it to them during their visit

·       The potential exists for a patient to be physiologically stable on a ventilator, but intolerant of decannulation; early discussions are necessary to determine reasonable expectations of care

·       Be sure to anticipate a second wave of patients, comprised of cancer patients for whom treatments and surgery have been delayed!

 

Tumor-Specific Learnings

 

Ø  Strategies in Breast Cancer:

·       In patients with early-stage disease, promote the use of neoadjuvant therapy where possible to delay the need for surgery

·       For patients with metastatic disease in the palliative setting, transition to less frequent chemotherapy dosing if possible

·       While growth factors may pose a risk in interstitial lung disease, new guidelines are emerging

 

Ø  Strategies in Melanoma:

·       The melanoma community has released specific recommendations for treatment during the pandemic:  https://www.nccn.org/covid-19/pdf/Melanoma.pdf

·       The use of BRAF/MEK inhibitors can cause fevers that are drug-related, and access to an alternate clinic where patients can be assessed is a useful resource

 

Ø  Strategies in Lung Cancer:

·       For patients who are stable on an oral, targeted therapy, telehealth check-in is a good option

·       For patients who progress on targeted therapies, increased use of liquid biopsies when appropriate can minimize use of bronchoscopy suites and other resources

·       For patients on pembrolizumab monotherapy, consider switching to a six-week dosing of 400 mg

·       Many lung cancer patients worry about “discrimination” should they develop a COVID infection; it is important to support patients and help manage expectations and concerns

 

UPDATED 5/11/2020

Townhall on COVID-19 and Cancer Care with Leading Oncologists Series 4

Addressing the Challenges of Cancer Care in the Community

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Medicine in 2045 – Perspectives by World Thought Leaders in the Life Sciences & Medicine

Reporter: Aviva Lev-Ari, PhD, RN

 

This report is based on an article in Nature Medicine | VOL 25 | December 2019 | 1800–1809 | http://www.nature.com/naturemedicine

Looking forward 25 years: the future of medicine.

Nat Med 25, 1804–1807 (2019) doi:10.1038/s41591-019-0693-y

 

Aviv Regev, PhD

Core member and chair of the faculty, Broad Institute of MIT and Harvard; director, Klarman Cell Observatory, Broad Institute of MIT and Harvard; professor of biology, MIT; investigator, Howard Hughes Medical Institute; founding co-chair, Human Cell Atlas.

  • millions of genome variants, tens of thousands of disease-associated genes, thousands of cell types and an almost unimaginable number of ways they can combine, we had to approximate a best starting point—choose one target, guess the cell, simplify the experiment.
  • In 2020, advances in polygenic risk scores, in understanding the cell and modules of action of genes through genome-wide association studies (GWAS), and in predicting the impact of combinations of interventions.
  • we need algorithms to make better computational predictions of experiments we have never performed in the lab or in clinical trials.
  • Human Cell Atlas and the International Common Disease Alliance—and in new experimental platforms: data platforms and algorithms. But we also need a broader ecosystem of partnerships in medicine that engages interaction between clinical experts and mathematicians, computer scientists and engineers

Feng Zhang, PhD

investigator, Howard Hughes Medical Institute; core member, Broad Institute of MIT and Harvard; James and Patricia Poitras Professor of Neuroscience, McGovern Institute for Brain Research, MIT.

  • fundamental shift in medicine away from treating symptoms of disease and toward treating disease at its genetic roots.
  • Gene therapy with clinical feasibility, improved delivery methods and the development of robust molecular technologies for gene editing in human cells, affordable genome sequencing has accelerated our ability to identify the genetic causes of disease.
  • 1,000 clinical trials testing gene therapies are ongoing, and the pace of clinical development is likely to accelerate.
  • refine molecular technologies for gene editing, to push our understanding of gene function in health and disease forward, and to engage with all members of society

Elizabeth Jaffee, PhD

Dana and Albert “Cubby” Broccoli Professor of Oncology, Johns Hopkins School of Medicine; deputy director, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins.

  • a single blood test could inform individuals of the diseases they are at risk of (diabetes, cancer, heart disease, etc.) and that safe interventions will be available.
  • developing cancer vaccines. Vaccines targeting the causative agents of cervical and hepatocellular cancers have already proven to be effective. With these technologies and the wealth of data that will become available as precision medicine becomes more routine, new discoveries identifying the earliest genetic and inflammatory changes occurring within a cell as it transitions into a pre-cancer can be expected. With these discoveries, the opportunities to develop vaccine approaches preventing cancers development will grow.

Jeremy Farrar, OBE FRCP FRS FMedSci

Director, Wellcome Trust.

  • shape how the culture of research will develop over the next 25 years, a culture that cares more about what is achieved than how it is achieved.
  • building a creative, inclusive and open research culture will unleash greater discoveries with greater impact.

John Nkengasong, PhD

Director, Africa Centres for Disease Control and Prevention.

  • To meet its health challenges by 2050, the continent will have to be innovative in order to leapfrog toward solutions in public health.
  • Precision medicine will need to take center stage in a new public health order— whereby a more precise and targeted approach to screening, diagnosis, treatment and, potentially, cure is based on each patient’s unique genetic and biologic make-up.

Eric Topol, MD

Executive vice-president, Scripps Research Institute; founder and director, Scripps Research Translational Institute.

  • In 2045, a planetary health infrastructure based on deep, longitudinal, multimodal human data, ideally collected from and accessible to as many as possible of the 9+ billion people projected to then inhabit the Earth.
  • enhanced capabilities to perform functions that are not feasible now.
  • AI machines’ ability to ingest and process biomedical text at scale—such as the corpus of the up-to-date medical literature—will be used routinely by physicians and patients.
  • the concept of a learning health system will be redefined by AI.

Linda Partridge, PhD

Professor, Max Planck Institute for Biology of Ageing.

  • Geroprotective drugs, which target the underlying molecular mechanisms of ageing, are coming over the scientific and clinical horizons, and may help to prevent the most intractable age-related disease, dementia.

Trevor Mundel, MD

President of Global Health, Bill & Melinda Gates Foundation.

  • finding new ways to share clinical data that are as open as possible and as closed as necessary.
  • moving beyond drug donations toward a new era of corporate social responsibility that encourages biotechnology and pharmaceutical companies to offer their best minds and their most promising platforms.
  • working with governments and multilateral organizations much earlier in the product life cycle to finance the introduction of new interventions and to ensure the sustainable development of the health systems that will deliver them.
  • deliver on the promise of global health equity.

Josep Tabernero, MD, PhD

Vall d’Hebron Institute of Oncology (VHIO); president, European Society for Medical Oncology (2018–2019).

  • genomic-driven analysis will continue to broaden the impact of personalized medicine in healthcare globally.
  • Precision medicine will continue to deliver its new paradigm in cancer care and reach more patients.
  • Immunotherapy will deliver on its promise to dismantle cancer’s armory across tumor types.
  • AI will help guide the development of individually matched
  • genetic patient screenings
  • the promise of liquid biopsy policing of disease?

Pardis Sabeti, PhD

Professor, Harvard University & Harvard T.H. Chan School of Public Health and Broad Institute of MIT and Harvard; investigator, Howard Hughes Medical Institute.

  • the development and integration of tools into an early-warning system embedded into healthcare systems around the world could revolutionize infectious disease detection and response.
  • But this will only happen with a commitment from the global community.

Els Toreele, PhD

Executive director, Médecins Sans Frontières Access Campaign

  • we need a paradigm shift such that medicines are no longer lucrative market commodities but are global public health goods—available to all those who need them.
  • This will require members of the scientific community to go beyond their role as researchers and actively engage in R&D policy reform mandating health research in the public interest and ensuring that the results of their work benefit many more people.
  • The global research community can lead the way toward public-interest driven health innovation, by undertaking collaborative open science and piloting not-for-profit R&D strategies that positively impact people’s lives globally.

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

Effective humoral immune responses to infection and immunization are defined by high-affinity antibodies generated as a result of B cell differentiation and selection that occurs within germinal centers (GC). Within the GC, B cells undergo affinity maturation, an iterative and competitive process wherein B cells mutate their immunoglobulin genes (somatic hypermutation) and undergo clonal selection by competing for T cell help. Balancing the decision to remain within the GC and continue participating in affinity maturation or to exit the GC as a plasma cell (PC) or memory B cell (MBC) is critical for achieving optimal antibody avidity, antibody quantity, and establishing immunological memory in response to immunization or infection. Humoral immune responses during chronic infections are often dysregulated and characterized by hypergammaglobulinemia, decreased affinity maturation, and delayed development of neutralizing antibodies. Previous studies have suggested that poor antibody quality is in part due to deletion of B cells prior to establishment of the GC response.

 

In fact the impact of chronic infections on B cell fate decisions in the GC remains poorly understood. To address this question, researchers used single-cell transcriptional profiling of virus-specific GC B cells to test the hypothesis that chronic viral infection disrupted GC B cell fate decisions leading to suboptimal humoral immunity. These studies revealed a critical GC differentiation checkpoint that is disrupted by chronic infection, specifically at the point of dark zone re-entry. During chronic viral infection, virus-specific GC B cells were shunted towards terminal plasma cell (PC) or memory B cell (MBC) fates at the expense of continued participation in the GC. Early GC exit was associated with decreased B cell mutational burden and antibody quality. Persisting antigen and inflammation independently drove facets of dysregulation, with a key role for inflammation in directing premature terminal GC B cell differentiation and GC exit. Thus, the present research defines GC defects during chronic viral infection and identify a critical GC checkpoint that is short-circuited, preventing optimal maturation of humoral immunity.

 

Together, these studies identify a key GC B cell differentiation checkpoint that is dysregulated during chronic infection. Further, it was found that the chronic inflammatory environment, rather than persistent antigen, is sufficient to drive altered GC B cell differentiation during chronic infection even against unrelated antigens. However, the data also indicate that inflammatory circuits are likely linked to perception of antigen stimulation. Nevertheless, this study reveals a B cell-intrinsic program of transcriptional skewing in chronic viral infection that results in shunting out of the cyclic GC B cell process and early GC exit with consequences for antibody quality and hypergammaglobulinemia. These findings have implications for vaccination in individuals with pre-existing chronic infections where antibody responses are often ineffective and suggest that modulation of inflammatory pathways may be therapeutically useful to overcome impaired humoral immunity and foster affinity maturation during chronic viral infections.

 

References:

 

https://www.biorxiv.org/content/10.1101/849844v1

 

https://www.ncbi.nlm.nih.gov/pubmed/25656706

 

https://www.ncbi.nlm.nih.gov/pubmed/27653600

 

https://www.ncbi.nlm.nih.gov/pubmed/26912368

 

https://www.ncbi.nlm.nih.gov/pubmed/26799208

 

https://www.ncbi.nlm.nih.gov/pubmed/23001146

 

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

One of the most contagious diseases known to humankind, measles killed an average of 2.6 million people each year before a vaccine was developed, according to the World Health Organization. Widespread vaccination has slashed the death toll. However, lack of access to vaccination and refusal to get vaccinated means measles still infects more than 7 million people and kills more than 100,000 each year worldwide as reported by WHO. The cases are on the rise, tripling in early 2019 and some experience well-known long-term consequences, including brain damage and vision and hearing loss. Previous epidemiological research into immune amnesia suggests that death rates attributed to measles could be even higher, accounting for as much as 50 percent of all childhood mortality.

 

Over the last decade, evidence has mounted that the measles vaccine protects in two ways. It prevents the well-known acute illness with spots and fever and also appears to protect from other infections over the long term by giving general boost to the immune system. The measles virus can impair the body’s immune memory, causing so-called immune amnesia. By protecting against measles infection, the vaccine prevents the body from losing or “forgetting” its immune memory and preserves its resistance to other infections. Researchers showed that the measles virus wipes out 11% to 73% of the different antibodies that protect against viral and bacterial strains a person was previously immune to like from influenza to herpes virus to bacteria that cause pneumonia and skin infections.

 

This study at Harvard Medical School and their collaborators is the first to measure the immune damage caused by the virus and underscores the value of preventing measles infection through vaccination. The discovery that measles depletes people’s antibody repertoires, partially obliterating immune memory to most previously encountered pathogens, supports the immune amnesia hypothesis. It was found that those who survive measles gradually regain their previous immunity to other viruses and bacteria as they get re-exposed to them. But because this process may take months to years, people remain vulnerable in the meantime to serious complications of those infections and thus booster shots of routine vaccines may be required.

 

VirScan detects antiviral and antibacterial antibodies in the blood that result from current or past encounters with viruses and bacteria, giving an overall snapshot of the immune system. Researchers gathered blood samples from unvaccinated children during a 2013 measles outbreak in the Netherlands and used VirScan to measure antibodies before and two months after infection in 77 children who’d contracted the disease. The researchers also compared the measurements to those of 115 uninfected children and adults. Researchers found a striking drop in antibodies from other pathogens in the measles-infected children that clearly suggested a direct effect on the immune system resembling measles-induced immune amnesia.

 

Further tests revealed that severe measles infection reduced people’s overall immunity more than mild infection. This could be particularly problematic for certain categories of children and adults, the researchers said. The present study observed the effects in previously healthy children only. But, measles is known to hit malnourished children much harder, the degree of immune amnesia and its effects could be even more severe in less healthy populations. Inoculation with the MMR (measles, mumps, rubella) vaccine did not impair children’s overall immunity. The results align with decades of research. Ensuring widespread vaccination against measles would not only help prevent the expected 120,000 deaths that will be directly attributed to measles this year alone, but could also avert potentially hundreds of thousands of additional deaths attributable to the lasting damage to the immune system.

 

References:

 

https://hms.harvard.edu/news/inside-immune-amnesia?utm_source=Silverpop

 

https://science.sciencemag.org/content/366/6465/599

 

www.who.int/immunization/newsroom/measles-data-2019/en/

 

https://www.ncbi.nlm.nih.gov/pubmed/20636817

 

https://www.ncbi.nlm.nih.gov/pubmed/27157064

 

https://www.ncbi.nlm.nih.gov/pubmed/30797735

 

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

Obesity is a global concern that is associated with many chronic complications such as type 2 diabetes, insulin resistance (IR), cardiovascular diseases, and cancer. Growing evidence has implicated the digestive system, including its microbiota, gut-derived incretin hormones, and gut-associated lymphoid tissue in obesity and IR. During high fat diet (HFD) feeding and obesity, a significant shift occurs in the microbial populations within the gut, known as dysbiosis, which interacts with the intestinal immune system. Similar to other metabolic organs, including visceral adipose tissue (VAT) and liver, altered immune homeostasis has also been observed in the small and large intestines during obesity.

 

A link between the gut microbiota and the intestinal immune system is the immune-derived molecule immunoglobulin A (IgA). IgA is a B cell antibody primarily produced in dimeric form by plasma cells residing in the gut lamina propria (LP). Given the importance of IgA on intestinal–gut microbe immunoregulation, which is directly influenced by dietary changes, scientists hypothesized that IgA may be a key player in the pathogenesis of obesity and IR. Here, in this study it was demonstrate that IgA levels are reduced during obesity and the loss of IgA in mice worsens IR and increases intestinal permeability, microbiota encroachment, and downstream inflammation in metabolic tissues, including inside the VAT.

 

IgA deficiency alters the obese gut microbiota and its metabolic phenotype can be recapitulated into microbiota-depleted mice upon fecal matter transplantation. In addition, the researchers also demonstrated that commonly used therapies for diabetes such as metformin and bariatric surgery can alter cellular and stool IgA levels, respectively. These findings suggested a critical function for IgA in regulating metabolic disease and support the emerging role for intestinal immunity as an important modulator of systemic glucose metabolism.

 

Overall, the researchers demonstrated a critical role for IgA in regulating intestinal homeostasis, metabolic inflammation, and obesity-related IR. These findings identify intestinal IgA+ immune cells as mucosal mediators of whole-body glucose regulation in diet-induced metabolic disease. This research further emphasized the importance of the intestinal adaptive immune system and its interactions with the gut microbiota and innate immune system within the larger network of organs involved in the manifestation of metabolic disease.

 

Future investigation is required to determine the impact of IgA deficiency during obesity in humans and the role of metabolic disease in human populations with selective IgA deficiency, especially since human IgA deficiency is associated with an altered gut microbiota that cannot be fully compensated with IgM. However, the research identified IgA as a critical immunological molecule in the intestine that impacts systemic glucose homeostasis, and treatments targeting IgA-producing immune populations and SIgA may have therapeutic potential for metabolic disease.

 

References:

 

https://www.nature.com/articles/s41467-019-11370-y?elqTrackId=dc86e0c60f574542b033227afd0fdc8e

 

https://www.jci.org/articles/view/88879

 

https://www.nature.com/articles/nm.2353

 

https://diabetes.diabetesjournals.org/content/57/6/1470

 

https://www.sciencedirect.com/science/article/pii/S1550413115001047?via%3Dihub

 

https://www.sciencedirect.com/science/article/pii/S1550413115002326?via%3Dihub

 

https://www.sciencedirect.com/science/article/pii/S1931312814004636?via%3Dihub

 

https://www.nature.com/articles/nature15766

 

https://www.sciencedirect.com/science/article/pii/S1550413116000371?via%3Dihub

 

https://www.nature.com/articles/nm.2001

 

https://www.sciencedirect.com/science/article/abs/pii/S1550413118305047?via%3Dihub

 

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

When a baby is born through its mother’s birth canal, it is bathed in a soup of microbes. Those born by caesarean section (C-section) miss out on this bacterial baptism. The differences in microbe exposure at birth and later health could be caused by other factors, such as whether a mother takes antibiotics during her surgery, and whether a baby is breastfed or has a genetic predisposition to obesity. So, the researchers are sharply split on whether or not this missing of bacterial exposure increases the risk of chronic health problems such as obesity and asthma.

 

Researchers found that babies delivered surgically harboured different collections of bacteria than did those born vaginally. C-section babies, which comprise more than 30% of births in the United States, are also more prone to obesity and immune diseases such as diabetes. Experiments show that mice born by C-section are more prone to obesity and have impaired immune systems. There are fewer factors that could account for these differences in the rodents, which can be studied in controlled conditions, than in people.

 

A wave of clinical trials now under way could help to settle the question — and feed into the debate over whether seeding babies born by C-section with their mother’s vaginal bacteria is beneficial or potentially harmful. Several groups of researchers will be swabbing hundreds of C-section babies with their mother’s microbes, while comparing them to a control group. Each team plans to monitor its study participants over several years in the hope of learning more about how the collection of microbes in their bodies might influence weight, allergy risk and other factors.

 

But some scientists say that the trials could expose C-section babies to infection, or encourage mothers to try do-it-yourself swabbing, without much evidence that there is a benefit or risk. Moreover, there is no evidence that differing exposure to vaginal microbes at birth can help explain variation in people’s health over time. Presently the whole concept is in very much a state of uncertainty.

 

Researchers in near future will compare swabbed C-section babies with a placebo group and with infants delivered vaginally. They confirmed that their protocols will not increase the risk of infection for C-section babies. Scientists will also rigorously screen mothers participating in these trials for microbes such as HIV and group B streptococcus — a common vaginal bacterium that causes respiratory problems in newborns.

 

References:

 

https://www.nature.com/articles/d41586-019-02348-3?utm_source=Nature+Briefing

 

https://www.ncbi.nlm.nih.gov/pubmed/31431742

 

https://www.ncbi.nlm.nih.gov/pubmed/20566857

 

https://www.ncbi.nlm.nih.gov/pubmed/25452656

 

https://www.ncbi.nlm.nih.gov/pubmed/22939691

 

https://www.ncbi.nlm.nih.gov/pubmed/24030708

 

https://pharmaceuticalintelligence.com/2017/02/22/babys-microbiome-changing-due-to-caesarean-birth-and-formula-feeding/

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Newly Found Functions of B Cell

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

4.1.8

4.1.8   Newly Found Functions of B Cell, Volume 2 (Volume Two: Latest in Genomics Methodologies for Therapeutics: Gene Editing, NGS and BioInformatics, Simulations and the Genome Ontology), Part 4: Single Cell Genomics

The importance of B cells to human health is more than what is already known. Vaccines capable of eradicating disease activate B cells, cancer checkpoint blockade therapies are produced using B cells, and B cell deficiencies have devastating impacts. B cells have been a subject of fascination since at least the 1800s. The notion of a humoral branch to immunity emerged from the work of and contemporaries studying B cells in the early 1900s.

Efforts to understand how we could make antibodies from B cells against almost any foreign surface while usually avoiding making them against self, led to Burnet’s clonal selection theory. This was followed by the molecular definition of how a diversity of immunoglobulins can arise by gene rearrangement in developing B cells. Recombination activating gene (RAG)-dependent processes of V-(D)-J rearrangement of immunoglobulin (Ig) gene segments in developing B cells are now known to be able to generate an enormous amount of antibody diversity (theoretically at least 1016 possible variants).

With so much already known, B cell biology might be considered ‘‘done’’ with only incremental advances still to be made, but instead, there is great activity in the field today with numerous major challenges that remain. For example, efforts are underway to develop vaccines that induce broadly neutralizing antibody responses, to understand how autoantigen- and allergen-reactive antibodies arise, and to harness B cell-depletion therapies to correct non-autoantibody-mediated diseases, making it evident that there is still an enormous amount we do not know about B cells and much work to be done.

Multiple self-tolerance checkpoints exist to remove autoreactive specificities from the B cell repertoire or to limit the ability of such cells to secrete autoantigen-binding antibody. These include receptor editing and deletion in immature B cells, competitive elimination of chronically autoantigen binding B cells in the periphery, and a state of anergy that disfavors PC (plasma cell) differentiation. Autoantibody production can occur due to failures in these checkpoints or in T cell self-tolerance mechanisms. Variants in multiple genes are implicated in increasing the likelihood of checkpoint failure and of autoantibody production occurring.

Autoantibodies are pathogenic in a number of human diseases including SLE (Systemic lupus erythematosus), pemphigus vulgaris, Grave’s disease, and myasthenia gravis. B cell depletion therapy using anti-CD20 antibody has been protective in some of these diseases such as pemphigus vulgaris, but not others such as SLE and this appears to reflect the contribution of SLPC (Short lived plasma cells) versus LLPC (Long lived plasma cells) to autoantibody production and the inability of even prolonged anti-CD20 treatment to eliminate the later. These clinical findings have added to the importance of understanding what factors drive SLPC versus LLPC development and what the requirements are to support LLPCs.

B cell depletion therapy has also been efficacious in several other autoimmune diseases, including multiple sclerosis (MS), type 1 diabetes, and rheumatoid arthritis (RA). While the potential contributions of autoantibodies to the pathology of these diseases are still being explored, autoantigen presentation has been posited as another mechanism for B cell disease-promoting activity.

In addition to autoimmunity, B cells play an important role in allergic diseases. IgE antibodies specific for allergen components sensitize mast cells and basophils for rapid degranulation in response to allergen exposures at various sites, such as in the intestine (food allergy), nose (allergic rhinitis), and lung (allergic asthma). IgE production may thus be favored under conditions that induce weak B cell responses and minimal GC (Germinal center) activity, thereby enabling IgE+ B cells and/or PCs to avoid being outcompeted by IgG+ cells. Aside from IgE antibodies, B cells may also contribute to allergic inflammation through their interactions with T cells.

B cells have also emerged as an important source of the immunosuppressive cytokine IL-10. Mouse studies revealed that B cell-derived IL-10 can promote recovery from EAE (Experimental autoimmune encephalomyelitis) and can be protective in models of RA and type 1 diabetes. Moreover, IL-10 production from B cells restrains T cell responses during some viral and bacterial infections. These findings indicate that the influence of B cells on the cytokine milieu will be context dependent.

The presence of B cells in a variety of solid tumor types, including breast cancer, ovarian cancer, and melanoma, has been associated in some studies with a positive prognosis. The mechanism involved is unclear but could include antigen presentation to CD4 and CD8 T cells, antibody production and subsequent enhancement of presentation, or by promoting tertiary lymphoid tissue formation and local T cell accumulation. It is also noteworthy that B cells frequently make antibody responses to cancer antigens and this has led to efforts to use antibodies from cancer patients as biomarkers of disease and to identify immunotherapy targets.

Malignancies of B cells themselves are a common form of hematopoietic cancer. This predilection arises because the gene modifications that B cells undergo during development and in immune responses are not perfect in their fidelity, and antibody responses require extensive B cell proliferation. The study of B cell lymphomas and their associated genetic derangements continues to be illuminating about requirements for normal B cell differentiation and signaling while also leading to the development of targeted therapies.

Overall this study attempted to capture some of the advances in the understanding of B cell biology that have occurred since the turn of the century. These include important steps forward in understanding how B cells encounter antigens, the co-stimulatory and cytokine requirements for their proliferation and differentiation, and how properties of the B cell receptor, the antigen, and helper T cells influence B cell responses. Many advances continue to transform the field including the impact of deep sequencing technologies on understanding B cell repertoires, the IgA-inducing microbiome, and the genetic defects in humans that compromise or exaggerate B cell responses or give rise to B cell malignancies.

Other advances that are providing insight include:

  • single-cell approaches to define B cell heterogeneity,
  • glycomic approaches to study effector sugars on antibodies,
  • new methods to study human B cell responses including CRISPR-based manipulation, and
  • the use of systems biology to study changes at the whole organism level.

With the recognition that B cells and antibodies are involved in most types of immune response and the realization that inflammatory processes contribute to a wider range of diseases than previously believed, including, for example, metabolic syndrome and neurodegeneration, it is expected that further

  • basic research-driven discovery about B cell biology will lead to more and improved approaches to maintain health and fight disease in the future.

References:

https://www.cell.com/cell/fulltext/S0092-8674(19)30278-8

https://onlinelibrary.wiley.com/doi/full/10.1002/hon.2405

https://www.pnas.org/content/115/18/4743

https://onlinelibrary.wiley.com/doi/full/10.1111/all.12911

https://cshperspectives.cshlp.org/content/10/5/a028795

https://www.sciencedirect.com/science/article/abs/pii/S0049017218304955

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The Journey of Antibiotic Discovery

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

The term ‘antibiotic’ was introduced by Selman Waksman as any small molecule, produced by a microbe, with antagonistic properties on the growth of other microbes. An antibiotic interferes with bacterial survival via a specific mode of action but more importantly, at therapeutic concentrations, it is sufficiently potent to be effective against infection and simultaneously presents minimal toxicity. Infectious diseases have been a challenge throughout the ages. From 1347 to 1350, approximately one-third of Europe’s population perished to Bubonic plague. Advances in sanitary and hygienic conditions sufficed to control further plague outbreaks. However, these persisted as a recurrent public health issue. Likewise, infectious diseases in general remained the leading cause of death up to the early 1900s. The mortality rate shrunk after the commercialization of antibiotics, which given their impact on the fate of mankind, were regarded as a ‘medical miracle’. Moreover, the non-therapeutic application of antibiotics has also greatly affected humanity, for instance those used as livestock growth promoters to increase food production after World War II.

 

Currently, more than 2 million North Americans acquire infections associated with antibiotic resistance every year, resulting in 23,000 deaths. In Europe, nearly 700 thousand cases of antibiotic-resistant infections directly develop into over 33,000 deaths yearly, with an estimated cost over €1.5 billion. Despite a 36% increase in human use of antibiotics from 2000 to 2010, approximately 20% of deaths worldwide are related to infectious diseases today. Future perspectives are no brighter, for instance, a government commissioned study in the United Kingdom estimated 10 million deaths per year from antibiotic resistant infections by 2050.

 

The increase in antibiotic-resistant bacteria, alongside the alarmingly low rate of newly approved antibiotics for clinical usage, we are on the verge of not having effective treatments for many common infectious diseases. Historically, antibiotic discovery has been crucial in outpacing resistance and success is closely related to systematic procedures – platforms – that have catalyzed the antibiotic golden age, namely the Waksman platform, followed by the platforms of semi-synthesis and fully synthetic antibiotics. Said platforms resulted in the major antibiotic classes: aminoglycosides, amphenicols, ansamycins, beta-lactams, lipopeptides, diaminopyrimidines, fosfomycins, imidazoles, macrolides, oxazolidinones, streptogramins, polymyxins, sulphonamides, glycopeptides, quinolones and tetracyclines.

 

The increase in drug-resistant pathogens is a consequence of multiple factors, including but not limited to high rates of antimicrobial prescriptions, antibiotic mismanagement in the form of self-medication or interruption of therapy, and large-scale antibiotic use as growth promotors in livestock farming. For example, 60% of the antibiotics sold to the USA food industry are also used as therapeutics in humans. To further complicate matters, it is estimated that $200 million is required for a molecule to reach commercialization, with the risk of antimicrobial resistance rapidly developing, crippling its clinical application, or on the opposing end, a new antibiotic might be so effective it is only used as a last resort therapeutic, thus not widely commercialized.

 

Besides a more efficient management of antibiotic use, there is a pressing need for new platforms capable of consistently and efficiently delivering new lead substances, which should attend their precursors impressively low rates of success, in today’s increasing drug resistance scenario. Antibiotic Discovery Platforms are aiming to screen large libraries, for instance the reservoir of untapped natural products, which is likely the next antibiotic ‘gold mine’. There is a void between phenotanypic screening (high-throughput) and omics-centered assays (high-information), where some mechanistic and molecular information complements antimicrobial activity, without the laborious and extensive application of various omics assays. The increasing need for antibiotics drives the relentless and continuous research on the foreground of antibiotic discovery. This is likely to expand our knowledge on the biological events underlying infectious diseases and, hopefully, result in better therapeutics that can swing the war on infectious diseases back in our favor.

 

During the genomics era came the target-based platform, mostly considered a failure due to limitations in translating drugs to the clinic. Therefore, cell-based platforms were re-instituted, and are still of the utmost importance in the fight against infectious diseases. Although the antibiotic pipeline is still lackluster, especially of new classes and novel mechanisms of action, in the post-genomic era, there is an increasingly large set of information available on microbial metabolism. The translation of such knowledge into novel platforms will hopefully result in the discovery of new and better therapeutics, which can sway the war on infectious diseases back in our favor.

 

References:

 

https://www.mdpi.com/2079-6382/8/2/45/htm

 

https://www.ncbi.nlm.nih.gov/pubmed/19515346

 

https://www.ajicjournal.org/article/S0196-6553(11)00184-2/fulltext

 

https://www.ncbi.nlm.nih.gov/pubmed/21700626

 

http://www.med.or.jp/english/journal/pdf/2009_02/103_108.pdf

 

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