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Archive for the ‘Stem Cells for Regenerative Medicine’ Category


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

 

Parkinson’s Disease (PD), characterized by both motor and non-motor system pathology, is a common neurodegenerative disorder affecting about 1% of the population over age 60. Its prevalence presents an increasing social burden as the population ages. Since its introduction in the 1960’s, dopamine (DA)-replacement therapy (e.g., L-DOPA) has remained the gold standard treatment. While improving PD patients’ quality of life, the effects of treatment fade with disease progression and prolonged usage of these medications often (>80%) results in side effects including dyskinesias and motor fluctuations. Since the selective degeneration of A9 mDA neurons (mDANs) in the substantia nigra (SN) is a key pathological feature of the disease and is directly associated with the cardinal motor symptoms, dopaminergic cell transplantation has been proposed as a therapeutic strategy.

 

Researchers showed that mammalian fibroblasts can be converted into embryonic stem cell (ESC)-like induced pluripotent stem cells (iPSCs) by introducing four transcription factors i.e., Oct4, Sox2, Klf4, and c-Myc. This was then accomplished with human somatic cells, reprogramming them into human iPSCs (hiPSCs), offering the possibility of generating patient-specific stem cells. There are several major barriers to implementation of hiPSC-based cell therapy for PD. First, probably due to the limited understanding of the reprogramming process, wide variability exists between the differentiation potential of individual hiPSC lines. Second, the safety of hiPSC-based cell therapy has yet to be fully established. In particular, since any hiPSCs that remain undifferentiated or bear sub-clonal tumorigenic mutations have neoplastic potential, it is critical to eliminate completely such cells from a therapeutic product.

 

In the present study the researchers established human induced pluripotent stem cell (hiPSC)-based autologous cell therapy. Researchers reported a platform of core techniques for the production of mDA progenitors as a safe and effective therapeutic product. First, by combining metabolism-regulating microRNAs with reprogramming factors, a method was developed to more efficiently generate clinical grade iPSCs, as evidenced by genomic integrity and unbiased pluripotent potential. Second, a “spotting”-based in vitro differentiation methodology was established to generate functional and healthy mDA cells in a scalable manner. Third, a chemical method was developed that safely eliminates undifferentiated cells from the final product. Dopaminergic cells thus produced can express high levels of characteristic mDA markers, produce and secrete dopamine, and exhibit electrophysiological features typical of mDA cells. Transplantation of these cells into rodent models of PD robustly restored motor dysfunction and reinnervated host brain, while showing no evidence of tumor formation or redistribution of the implanted cells.

 

Together these results supported the promise of these techniques to provide clinically applicable personalized autologous cell therapy for PD. It was recognized by researchers that this methodology is likely to be more costly in dollars and manpower than techniques using off-the-shelf methods and allogenic cell lines. Nevertheless, the cost for autologous cell therapy may be expected to decrease steadily with technological refinement and automation. Given the significant advantages inherent in a cell source free of ethical concerns and with the potential to obviate the need for immunosuppression, with its attendant costs and dangers, it was proposed that this platform is suitable for the successful implementation of human personalized autologous cell therapy for PD.

 

References:

 

https://www.jci.org/articles/view/130767/pdf?elqTrackId=2fd7d0edee744f9cb6d70a686d7b273b

 

https://www.ncbi.nlm.nih.gov/pubmed/31714896

 

https://www.ncbi.nlm.nih.gov/pubmed/23666606

 

https://www.ncbi.nlm.nih.gov/pubmed/27343168

 

https://www.ncbi.nlm.nih.gov/pubmed/21495962

 

https://www.ncbi.nlm.nih.gov/pubmed/28083784

 

https://www.ncbi.nlm.nih.gov/pubmed/20336395

 

https://www.ncbi.nlm.nih.gov/pubmed/28585381

 

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Immunoediting can be a constant defense in the cancer landscape


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

 

There are many considerations in the cancer immunoediting landscape of defense and regulation in the cancer hallmark biology. The cancer hallmark biology in concert with key controls of the HLA compatibility affinity mechanisms are pivotal in architecting a unique patient-centric therapeutic application. Selection of random immune products including neoantigens, antigens, antibodies and other vital immune elements creates a high level of uncertainty and risk of undesirable immune reactions. Immunoediting is a constant process. The human innate and adaptive forces can either trigger favorable or unfavorable immunoediting features. Cancer is a multi-disease entity. There are multi-factorial initiators in a certain disease process. Namely, environmental exposures, viral and / or microbiome exposure disequilibrium, direct harm to DNA, poor immune adaptability, inherent risk and an individual’s own vibration rhythm in life.

 

When a human single cell is crippled (Deranged DNA) with mixed up molecular behavior that is the initiator of the problem. A once normal cell now transitioned into full threatening molecular time bomb. In the modeling and creation of a tumor it all begins with the singular molecular crisis and crippling of a normal human cell. At this point it is either chop suey (mixed bit responses) or a productive defensive and regulation response and posture of the immune system. Mixed bits of normal DNA, cancer-laden DNA, circulating tumor DNA, circulating normal cells, circulating tumor cells, circulating immune defense cells, circulating immune inflammatory cells forming a moiety of normal and a moiety of mess. The challenge is to scavenge the mess and amplify the normal.

 

Immunoediting is a primary push-button feature that is definitely required to be hit when it comes to initiating immune defenses against cancer and an adaptation in favor of regression. As mentioned before that the tumor microenvironment is a “mixed bit” moiety, which includes elements of the immune system that can defend against circulating cancer cells and tumor growth. Personalized (Precision-Based) cancer vaccines must become the primary form of treatment in this case. Current treatment regimens in conventional therapy destroy immune defenses and regulation and create more serious complications observed in tumor progression, metastasis and survival. Commonly resistance to chemotherapeutic agents is observed. These personalized treatments will be developed in concert with cancer hallmark analytics and immunocentrics affinity and selection mapping. This mapping will demonstrate molecular pathway interface and HLA compatibility and adaptation with patientcentricity.

References:

 

https://www.linkedin.com/pulse/immunoediting-cancer-landscape-john-catanzaro/

 

https://www.cell.com/cell/fulltext/S0092-8674(16)31609-9

 

https://www.researchgate.net/publication/309432057_Circulating_tumor_cell_clusters_What_we_know_and_what_we_expect_Review

 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4190561/

 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5840207/

 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5593672/

 

https://www.frontiersin.org/articles/10.3389/fimmu.2018.00414/full

 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5593672/

 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4190561/

 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4388310/

 

https://www.linkedin.com/pulse/cancer-hallmark-analytics-omics-data-pathway-studio-review-catanzaro/

 

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Functioning Human Neural Networks Grown in 3-D from Stem Cells

Reporter: Irina Robu, PhD

 

Researchers at Tuffs University developed three-dimensional human tissue model that mimics structural and functional features of the brain and were able to demonstrate sustained neural activity over several months. The 3D brain tissue models were the result of a collaborative effort between researchers from Tufts University School of Engineering, Tufts University School of Medicine, the Sackler School of Graduate Biomedical Sciences at Tufts, and the Jackson Laboratory.

 

These tissue models have the ability to populate a 3D matrix of silk protein and collagen with cells from patients with Parkinson’s disease, Alzheimer’s disease and the ability to

  • explore cell interactions,
  • disease progression and
  • response to treatment.

The 3D brain tissue models overcome a crucial challenge of previous models which is the availability of human source neurons due to the fact that neurological tissues are rarely removed from

  • healthy patients, and are usually available
  • post-mortem from diseased patients.

The 3D tissue models are populated with human induced pluripotent stem cells (iPSCs) that can be derived from several sources, including patient skin. The iPSCs are generated by turning back the clock on cell development to their embryonic-like precursors. They can then be dialed forward again to any cell type, including neurons. The porous structure of the 3D tissue cultures labeled in the research delivers sufficient oxygenation, access for nutrients and measurement of cellular properties. A clear window in the center of each 3D matrix allows researchers to visualize the

  • growth,
  • organization and
  • behavior of individual cells.

According to David L. Kaplan, “the silk-collagen scaffolds provide the right environment to produce cells with the genetic signatures and electrical signaling found in native neuronal tissues”. Compared to growing and culturing cells in two dimensions, the three-dimensional matrix yields a knowingly extra complete mix of cells found in neural tissue, with the appropriate morphology and expression of receptors and neurotransmitters. Other researchers have used iPSCs to create brain-like organoids, but can still make it difficult figuring out what individual cells are doing in real time. Likewise, cells in the center of the organoids may not obtain enough oxygen or nutrients to function in a native state.

However, the researchers can see a great advantage of the 3D tissue models with advanced imaging techniques, and the addition of cell types such as

  • microglia and
  • endothelial cells,

to create a more complete model of the brain environment and the complex interactions that are involved in

  • signaling,
  • learning and plasticity, and
  • degeneration.

 

SOURCE

https://www.rdmag.com/news/2018/10/scientists-grow-functioning-human-neural-networks-3d-stem-cells

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NHLBI decision to halt Heart Stem-Cell Study (CONCERT-HF trial) due to concerns about Anversa’s Animal Studies, not due to any Data generated by the Clinical trial itself, no compromised patient safety by trial

Reporter: Aviva Lev-Ari, PhD, RN

Doubts about Anversa’s work arose in the early 2000s after other researchers failed to replicate his findings and questioned whether cardiac stem cells existed2,3,4.

Paper of Former HMS Prof. Withdrawn, Clinical Trial Paused after Harvard Requests Retractions

https://www.thecrimson.com/article/2018/10/31/medical-school-paper-retracted/

NHLBI NEWS

Statement

Statement on NHLBI decision to pause the CONCERT-HF trial

The National Heart, Lung, and Blood Institute (NHLBI), part of the National Institutes of Health, is pausing the CONCERT-HF trialexternal link, which involves patients with chronic heart failure. Recent calls for the retraction of journal articles in related fields of cell therapy research have raised concerns about the scientific foundations of this trial.  While none of the articles in question derive from the CONCERT-HF trial itself, the NHLBI convened CONCERT-HF’s Data and Safety Monitoring Board (DSMB) out of an abundance of caution to ensure the study continues to meet the highest standards for participant safety and scientific integrity. Informed by the DSMB recommendations of October 25, 2018, the NHLBI is pausing the trial. While the DSMB did not have any participant safety concerns, this pause enables the DSMB to complete its review.

The safety of all clinical trial participants is paramount to NHLBI. NHLBI will honor its commitment to CONCERT-HF participants and continue the follow-up protocol during this pause for all participants who have already been treated in the study. Participants are being notified of the status of the trial and how to request additional information.

The CONCERT-HF trial seeks to determine whether c-kit+ cells, either alone or in combination with mesenchymal stem cells derived from the bone marrow, are safe and benefit patients with chronic heart failure, who have very limited treatment options. Despite significant medical and surgical advances, patients with heart failure continue to experience a low quality of life and about half of them will die within five years of receiving a diagnosis.

The scientific basis of CONCERT-HF is supported by a body of evidence in several preclinical models in a number of studies in a variety of laboratories and was reviewed by a Protocol Review Committee (PRC) independent of the trial. The cell therapies that CONCERT-HF is testing are under an investigational new drug (IND) designation which is overseen by the U.S. Food and Drug Administration (FDA). The cells are produced by an accredited laboratory independent of the clinical sites. In addition, as part of standard oversight of clinical trials, the DSMB routinely reviews and monitors CONCERT-HF to ensure participant safety and that the study continues to ask compelling scientific questions with implications for patient care.

The DSMB’s review will be conducted as expeditiously as possible and will inform NHLBI’s future actions that will ensure the highest standards of participant safety and scientific integrity.

SOURCE

https://www.nhlbi.nih.gov/news/2018/statement-nhlbi-decision-pause-concert-hf-trial

References

  1. Quaini, F. et al. N. Engl. J. Med. 346, 5–15 (2002).
  1. Murry, C. E. et al. Nature 428, 664–668 (2004).
  1. Balsam, L. B. Nature 428, 668–673 (2004).
  1. Nygren, J. M. et al. Nature Med. 10, 494–501 (2004).

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LIVE 2018 The 21st Gabay Award to LORENZ STUDER, Memorial Sloan Kettering Cancer Center, contributions in stem cell biology and patient-specific, cell-based therapy

REAL TIME Reporter: Aviva Lev-Ari, PhD, RN

AWARD LECTURE

Tue., Oct. 9, 2018
4:00 PM
Shapiro Campus Center Theater
Brandeis University

CURRENT WINNER

lorenzstuder.jpgLORENZ STUDER

MACARTHUR FELLOWS PROGRAM

Lorenz Studer

Stem Cell Biologist | Class of 2015

Pioneering a new method for large-scale generation of dopaminergic neurons that could provide one of the first treatments for Parkinson’s disease and prove the broader feasibility of stem cell–based therapies for other neurological disorders.

https://www.macfound.org/fellows/947/

118 publications on PubMed

https://www.ncbi.nlm.nih.gov/pubmed/?term=LORENZ+STUDER

 

PRESIDING

Dagmar Ringe Professor of Biochemistry, Chemistry and Rosenstiel Basic Medical Sciences Research Center

WELCOME

Lisa Lynch Provost and Maurice B. Hexter Professor of Social and Economic Policy Brandeis University

 

RESPONSE Lorenz Studer, MD Director, Center for Stem Cell Biology Memorial Sloan Kettering Cancer Center Member, Developmental Biology Program Memorial Sloan Kettering Cancer Center

Fully defined protocol for all ectodermal lineage

  • Nervous system: Forebrain, Midbrain, Spinal cord:
  • CNS lineage to PNS Lineage
  • Excitatory cortical neurons
  • cortical interneurons Astrocytes
  • microglia
  • Age-reset disease – late-onset during reprogramming – Is age reversible?
  • Loss of age-related markers
  • iPSC-derived cells yield stage cell upon differentiation
  • In vitro differentiation techniques: 2D Directed Differentiation 3D- Organoids
  • Graded MORPHOGEN SIGNALING
  • DOXYCYLINE: ISHH-ORGANIZER – 5 discrete forebrain regions
  • Building Human brain cells in 2D and in 3D
  • Organized cells –>>>  directed organoids –>> Organized Organoids
  • Parkinson, 1817 – Essay on Shaky Palsy (Niagrostaterial pathway)
  • Genetics and related dysfunction: affecting PD
  • Charckot, 1889
  • PD – new approach following drugs and deep brain stimulation failure in advanced disease: Fetal tissue transplant trials: Fetal Grafting
  • graft-induced dyskinesia
  • Long term, 15 years positive effects
  • Stem-cell-based regenerative therapy could transform PD therapy
  • 1995  Fetal DA neuron grafting for PD in Switzerland
  • 1998 – midbrain stem cell derived DA neuron
  • 200-2003 – Stem cell in brain implantation in WashDC
  • 2011 – Behavioral assays that are restored in mice
  • Optogenetics: manipulating – Light on the brain – control animal’s neurons
  • MOA of Graft function
  • Dopamine neurons – Stratium area of the human brain
  • From bench to bedside – WNT boost enhances EN1 expression
  • Neuron melanin induction
  • Manufacturing and QA testing: GMP – Off the shelf Allogenic Product
  • 1,000 human dose equivalents
  • cryopreserve
  • MSK-DA01 is highly enriched for mDA neuron precursors without detectable hESC Contaminants
  • FDA feedback and final steps to IND – PRE-IND MEETING: 2014, 2016
  • GLP STUDIES:
  • TUMORIGENICITY, BIODISTRIBUTION AND TOXISITY
  • HISTOLOGY OF FINAL PRODUCT
  • CLINICAL TRIAL DESIGN – STEM-PD – MSK and Weill Cornell Medicine
  • HLA expression is absent in edited iPSC with expression of HLA-E to block NK clearance
  • FUTURE: CRISPR
  • ATLaS-PD – assessing the longitudinal Symptoms/signs to moderate of severe stage
  • Development of a new PD therapy from Pluripotent Stem Cells
  • BlueRock Therapeutics – MSK-PD – Start up – $240Million funding
  • Stem cell based dopamine therapy for PD
  • Immunosuppression for 12 months
  • defined levodopa response > 45% improvement
  • Conclusions
  • Cell banks for clinical trials
  • NY state Stem cell science consortia

http://www.brandeis.edu/rosenstiel/images/pdfs/gabbay21program.pdf

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New CRISPR Approach Transforms Skin Cells into Pluripotent Stem Cells

Reporter: Irina Robu, PhD

Dr. Timo Otonkoski, University of Helsinki and Dr.Juha Kere, King’s College London succeeded on reprograming skin cells into pluripotent stem cells by activating cell’s own genes using gene editing technology, CRISPR-Cas9-based gene activation (CRISPRa) that can be used to activate genes. The method uses a blunt version of Cas9 ‘gene scissors’ that does not cut DNA and can consequently be used to activate gene expression without mutating the genome. Previously, reprogramming was only possible by artificially introducing the critical transformation genes known as Yamanaka Factors into skin cells where they are normally inactive.

According to a study that is published in Nature Communication, called Human Pluripotent Reprogramming with CRISPR activators which show that CRISPRa is an attractive tool for cellular reprogramming applications due to its high multiplex capacity and direct alignment of endogenous loci. In the article, it is presented that reprogramming of primary human dermal fibroblasts to induced pluripotent stem cells with CRISPRa, the aimed at endogenous cells. The data shows that human body cells can only be reprogrammed into iPS cells with CRISPRa, and the findings reveal the involvement of EEA motif-associated mechanisms in cellular reprogramming.

The discovery also advocates that it might be likely to improve many other reprogramming tasks by addressing genetic elements that are typical of the intended target cell type. According to Jere Weltner, PhD student working on the project “the technology can find practical application in biobanking and many other applications of tissue technology.

SOURCE

https://www.sciencedaily.com/releases/2018/07/180706091723.htm

 

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

 

A heart-healthy diet has been the basis of atherosclerotic cardiovascular disease (ASCVD) prevention and treatment for decades. The potential cardiovascular (CV) benefits of specific individual components of the “food-ome” (defined as the vast array of foods and their constituents) are still incompletely understood, and nutritional science continues to evolve.

 

The scientific evidence base in nutrition is still to be established properly. It is because of the complex interplay between nutrients and other healthy lifestyle behaviours associated with changes in dietary habits. However, several controversial dietary patterns, foods, and nutrients have received significant media exposure and are stuck by hype.

 

Decades of research have significantly advanced our understanding of the role of diet in the prevention and treatment of ASCVD. The totality of evidence includes randomized controlled trials (RCTs), cohort studies, case-control studies, and case series / reports as well as systematic reviews and meta-analyses. Although a robust body of evidence from RCTs testing nutritional hypotheses is available, it is not feasible to obtain meaningful RCT data for all diet and health relationships.

 

Studying preventive diet effects on ASCVD outcomes requires many years because atherosclerosis develops over decades and may be cost-prohibitive for RCTs. Most RCTs are of relatively short duration and have limited sample sizes. Dietary RCTs are also limited by frequent lack of blinding to the intervention and confounding resulting from imperfect diet control (replacing 1 nutrient or food with another affects other aspects of the diet).

 

In addition, some diet and health relationships cannot be ethically evaluated. For example, it would be unethical to study the effects of certain nutrients (e.g., sodium, trans fat) on cardiovascular disease (CVD) morbidity and mortality because they increase major risk factors for CVD. Epidemiological studies have suggested associations among diet, ASCVD risk factors, and ASCVD events. Prospective cohort studies yield the strongest observational evidence because the measurement of dietary exposure precedes the development of the disease.

 

However, limitations of prospective observational studies include: imprecise exposure quantification; co-linearity among dietary exposures (e.g., dietary fiber tracks with magnesium and B vitamins); consumer bias, whereby consumption of a food or food category may be associated with non-dietary practices that are difficult to control (e.g., stress, sleep quality); residual confounding (some non-dietary risk factors are not measured); and effect modification (the dietary exposure varies according to individual/genetic characteristics).

 

It is important to highlight that many healthy nutrition behaviours occur with other healthy lifestyle behaviours (regular physical activity, adequate sleep, no smoking, among others), which may further confound results. Case-control studies are inexpensive, relatively easy to do, and can provide important insight about an association between an exposure and an outcome. However, the major limitation is how the study population is selected or how retrospective data are collected.

 

In nutrition studies that involve keeping a food diary or collecting food frequency information (i.e., recall or record), accurate memory and recording of food and nutrient intake over prolonged periods can be problematic and subject to error, especially before the diagnosis of disease.

 

The advent of mobile technology and food diaries may provide opportunities to improve accuracy of recording dietary intake and may lead to more robust evidence. Finally, nutrition science has been further complicated by the influences of funding from the private sector, which may have an influence on nutrition policies and practices.

 

So, the future health of the global population largely depends on a shift to healthier dietary patterns. Green leafy vegetables and antioxidant suppliments have significant cardio-protective properties when consumed daily. Plant-based proteins are significantly more heart-healthy compared to animal proteins.

 

However, in the search for the perfect dietary pattern and foods that provide miraculous benefits, consumers are vulnerable to unsubstantiated health benefit claims. As clinicians, it is important to stay abreast of the current scientific evidence to provide meaningful and effective nutrition guidance to patients for ASCVD risk reduction.

 

Available evidence supports CV benefits of nuts, olive oil and other liquid vegetable oils, plant-based diets and plant-based proteins, green leafy vegetables, and antioxidant-rich foods. Although juicing may be of benefit for individuals who would otherwise not consume adequate amounts of fresh fruits and vegetables, caution must be exercised to avoid excessive calorie intake. Juicing of fruits / vegetables with pulp removal increases calorie intake. Portion control is necessary to avoid weight gain and thus cardiovascular health.

 

There is currently no evidence to supplement regular intake of antioxidant dietary supplements. Gluten is an issue for those with gluten-related disorders, and it is important to be mindful of this in routine clinical practice; however, there is no evidence for CV or weight loss benefits, apart from the potential caloric restriction associated with a gluten free diet.

 

References:

 

https://www.ncbi.nlm.nih.gov/pubmed/28254181

 

https://www.sciencedirect.com/science/article/pii/S0735109713060294?via%3Dihub

 

http://circ.ahajournals.org/content/119/8/1161

 

http://refhub.elsevier.com/S0735-1097(17)30036-0/sref6

 

https://www.scopus.com/record/display.uri?eid=2-s2.0-0031709841&origin=inward&txGid=af40773f7926694c7f319d91efdcd40c

 

https://www.magonlinelibrary.com/doi/10.12968/hosp.2000.61.4.1875

 

https://jamanetwork.com/journals/jamainternalmedicine/article-abstract/2548255

 

https://pharmaceuticalintelligence.com/2018/05/31/supplements-offer-little-cv-benefit-and-some-are-linked-to-harm-in-j-am-coll-cardiol/

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