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Archive for the ‘Autoimmune Inflammatory DIseases’ Category


Curation of selected topics and articles on Role of G-Protein Coupled Receptors in Chronic Disease as supplemental information for #TUBiol3373

Curator: Stephen J. Williams, PhD 

Below is a series of posts and articles related to the role of G protein coupled receptors (GPCR) in various chronic diseases.  This is only a cursory collection and by no means represents the complete extensive literature on pathogenesis related to G protein function or alteration thereof.  However it is important to note that, although we think of G protein signaling as rather short lived, quick, their chronic activation may lead to progression of various disease. As to whether disease onset, via GPCR, is a result of sustained signal, loss of desensitization mechanisms, or alterations of transduction systems is an area to be investigated.

From:

Molecular Pathogenesis of Progressive Lung Diseases

Author: Larry H. Bernstein, MD, FCAP

 

Chronic Obstructive Lung Disease (COPD)

Inflammatory and infectious factors are present in diseased airways that interact with G-protein coupled receptors (GPCRs), such as purinergic receptors and bradykinin (BK) receptors, to stimulate phospholipase C [PLC]. This is followed by the activation of inositol 1,4,5-trisphosphate (IP3)-dependent activation of IP3 channel receptors in the ER, which results in channel opening and release of stored Ca2+ into the cytoplasm. When ER Ca2+ stores are depleted a pathway for Ca2+ influx across the plasma membrane is activated. This has been referred to as “capacitative Ca2+ entry”, and “store-operated calcium entry” (3). In the next step PLC mediated Ca2+ i is mobilized as a result of GPCR activation by inflammatory mediators, which triggers cytokine production by Ca2+ i-dependent activation of the transcription factor nuclear factor kB (NF-kB) in airway epithelia.

 

 

 

In Alzheimer’s Disease

Important Lead in Alzheimer’s Disease Model

Larry H. Bernstein, MD, FCAP, Curator discusses findings from a research team at University of California at San Diego (UCSD) which the neuropeptide hormone corticotropin-releasing factor (CRF) as having an important role in the etiology of Alzheimer’s Disease (AD). CRF activates the CRF receptor (a G stimulatory receptor).  It was found inhibition of the CRF receptor prevented cognitive impairment in a mouse model of AD.  Furthermore researchers at the Flanders Interuniversity Institute for Biotechnology found the loss of a protein called G protein-coupled receptor 3 (GPR3) may lower the amyloid plaque aggregation, resulting in improved cognitive function.  Additionally inhibition of several G-protein coupled receptors alter amyloid precursor processing, providing a further mechanism of the role of GPCR in AD (see references in The role of G protein-coupled receptors in the pathology of Alzheimer’s disease by Amantha Thathiah and Bart De Strooper Nature Reviews Feb 2011; 12: 73-87 and read post).

 

In Cardiovascular and Thrombotic Disease

 

Adenosine Receptor Agonist Increases Plasma Homocysteine

 

and read related articles in curation on effects of hormones on the cardiovascular system at

Action of Hormones on the Circulation

 

In Cancer

A Curated History of the Science Behind the Ovarian Cancer β-Blocker Trial

 

Further curations and references of G proteins and chronic disease can be found at the Open Access journal https://pharmaceuticalintelligence.com using the search terms “GCPR” and “disease” in the Search box in the upper right of the home page.

 

 

 

 

 

 

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Benefits of Fiber in Diet

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

 

Food is digested by bathing in enzymes that break down its molecules. Those molecular fragments then pass through the gut wall and are absorbed in our intestines. But our bodies make a limited range of enzymes, so that we cannot break down many of the tough compounds in plants. The term “dietary fiber” refers to those indigestible molecules. These dietary fibers are indigestible only to us. The gut is coated with a layer of mucus, on which sits a carpet of hundreds of species of bacteria, part of the human microbiome. Some of these microbes carry the enzymes needed to break down various kinds of dietary fibers.

 

Scientists at the University of Gothenburg in Sweden are running experiments that are yielding some important new clues about fiber’s role in human health. Their research indicates that fiber doesn’t deliver many of its benefits directly to our bodies. Instead, the fiber we eat feeds billions of bacteria in our guts. Keeping them happy means our intestines and immune systems remain in good working order. The scientists have recently reported that the microbes are involved in the benefits obtained from the fruits-and-vegetables diet. Research proved that low fiber diet decreases the gut bacteria population by tenfold.

 

Along with changes to the microbiome there were also rapid changes observed in the experimental mice. Their intestines got smaller, and its mucus layer thinner. As a result, bacteria wound up much closer to the intestinal wall, and that encroachment triggered an immune reaction. After a few days on the low-fiber diet, mouse intestines developed chronic inflammation. After a few weeks, they started putting on fat and developing higher blood sugar levels. Inflammation can help fight infections, but if it becomes chronic, it can harm our bodies. Among other things, chronic inflammation may interfere with how the body uses the calories in food, storing more of it as fat rather than burning it for energy.

 

In a way fiber benefits human health is by giving, indirectly, another source of food. When bacteria finished harvesting the energy in the dietary fiber, they cast off the fragments as waste. That waste — in the form of short-chain fatty acids — is absorbed by intestinal cells, which use it as fuel. But the gut’s microbes do more than just make energy. They also send messages. Intestinal cells rely on chemical signals from the bacteria to work properly. The cells respond to the signals by multiplying and making a healthy supply of mucus. They also release bacteria-killing molecules. By generating these responses, gut bacteria help to maintain a peaceful coexistence with the immune system. They rest on the gut’s mucus layer at a safe distance from the intestinal wall. Any bacteria that wind up too close get wiped out by antimicrobial poisons.

 

A diet of fiber-rich foods, such as fruits and vegetables, reduces the risk of developing diabetes, heart disease and arthritis. Eating more fiber seems to lower people’s mortality rate, whatever be the cause. Researchers hope that they will learn more about how fiber influences the microbiome to use it as a way to treat disorders. Lowering inflammation with fiber may also help in the treatment of immune disorders such as inflammatory bowel disease. Fiber may also help reverse obesity. They found that fiber supplements helped obese people to lose weight. It’s possible that each type of fiber feeds a particular set of bacteria, which send their own important signals to our bodies.

 

References:

 

https://www.nytimes.com/2018/01/01/science/food-fiber-microbiome-inflammation.html

 

 

https://www.ncbi.nlm.nih.gov/pubmed/29276171

 

https://www.ncbi.nlm.nih.gov/pubmed/29276170

 

https://www.ncbi.nlm.nih.gov/pubmed/29486139

 

https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/fiber/art-20043983

 

https://nutritiouslife.com/eat-empowered/high-fiber-diet/

 

http://www.eatingwell.com/article/287742/10-amazing-health-benefits-of-eating-more-fiber/

 

http://www.cookinglight.com/eating-smart/nutrition-101/what-is-a-high-fiber-diet

 

https://www.helpguide.org/articles/healthy-eating/high-fiber-foods.htm

 

https://www.gicare.com/diets/high-fiber-diet/

 

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Expanding area of Tolerance-inducing Autoimmune Disease Therapeutics: Key Players

Reporter: Aviva Lev-Ari, PhD, RN

Patients with autoimmune diseases have immune systems that see natural proteins as foreign and attack them. Anokion’s approach to treating such diseases is to use tolerance mechanisms in the body to reeducate the immune system. The company’s technology also allows it to create proteins masked as native to the body that can dial down immune system responses to beneficial drugs.

Key Players in Tolerance-inducing Autoimmune Disease Therapeutics

  • Swiss biotech Anokion has sealed a multimillion dollar deal with Celgene to develop candidates in the expanding area of tolerance-inducing autoimmune disease therapeutics. The deal gives Celgene an equity interest in Anokion and the exclusive right to acquire the smaller drugmaker at undisclosed but pre-specified “option exercise points.” The privately-held company stands to receive $45 million upfront under the collaboration and could bring in an additional $10 million if they reach certain preclinical development milestones.
  • Parvus Therapeutics, with programs in type 1 diabetes, multiple sclerosis and liver disease in preclinical development, and
  • Selecta Biosciences, whose immune tolerance pipeline includes type 1 diabetes and celiac disease.

The global autoimmune disease market could be worth almost $16 billion by 2022, with a projected compound annual growth rate of almost 4%, according an April report from market intelligence firm Intelliroi.

 

SOURCE

http://www.biopharmadive.com/news/celgene-anokion-option-takeover-autoimmune/433707/

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LIVE 9/21 3:20PM to 6:40PM KINASE INHIBITORS FOR CANCER IMMUNOTHERAPY COMBINATIONS & KINASE INHIBITORS FOR AUTOIMMUNE AND INFLAMMATORY DISEASES at CHI’s 14th  Discovery On Target, 9/19 – 9/22/2016, Westin Boston Waterfront, Boston

http://www.discoveryontarget.com/

http://www.discoveryontarget.com/crispr-therapies/

Leaders in Pharmaceutical Business Intelligence (LPBI) Group is a

Media Partner of CHI for CHI’s 14th Annual Discovery on Target taking place September 19 – 22, 2016 in Boston.

In Attendance, streaming LIVE using Social Media

Aviva Lev-Ari, PhD, RN

Editor-in-Chief

http://pharmaceuticalintelligence.com

#BostonDOT16

@BostonDOT

 

KINASE INHIBITORS FOR CANCER IMMUNOTHERAPY COMBINATIONS

3:20 Chairperson’s Opening Remarks

Guido J.R. Zaman, Ph.D., Managing Director & Head of Biology, Netherlands Translational Research Center B.V. (NTRC)

3:25 FEATURED PRESENTATION: Inhibition of PI3K and Tubulin

Doriano_Fabbro

Doriano Fabbro, Ph.D., CSO, PIQUR Therapeutics

The PI3K signaling pathway is frequently activated in tumors. PQR309 is a selective dual inhibitor of PI3K and mTOR (currently in Phase I) in cancer patients. The preclinical pharmacology and toxicology of PQR309 is presented, including its activity in lymphoma preclinical models. In addition, we elucidate structural factors defining the PI3K inhibitory activity and tubulin-binding of PQR309 derivatives.

  • PQR309 & GDC0941 arrest cells i G1/S (typical for PI3K/mTOR Inhibitor)
  • What drives Antiproliferative Activity of BKM120: PI3K or MT or both?
  • BKM120 Binds to beta-Tubulin/alpha -Tubulin Interfere
  • T2R-TTL complex
  • Orientation of BKM120 in PI3K
  • PQR309 – is a brain penetrating, PK and BAV by PO, good metabolic stability
  • PQR309 ANti-proliferative in Lymphoma
  • Clinical efficacy – Now in Phase II

4:05 Design and Development of a Novel PI3K-p110β/δ Inhibitor, KA2237 with Combined Tumor Immunotherapeutic, Growth Inhibition and Anti-Metastatic Activity

Stephen_Shuttleworth

Stephen Shuttleworth, Ph.D., FRSC, CChem, CSO, Karus Therapeutics Ltd.

The design and development of KA2237, a novel and selective inhibitor of PI3K-p110β/δ, will be described. This molecule has clinical potential in the treatment of solid and hematological malignancies, through its direct inhibition of tumor growth and metastatic spread, and through immunotherapeutic mechanisms. Phase I studies for KA2237 are scheduled to commence in Q2 2016 at the MD Anderson Cancer Center.

  • Design & Development of Novel, Oral, selective PI3K enzyme family: CLass I,II, III, IV based upon:
  • Class I IA IB
  • KA2237: DUal PI3K – p110beta/delta-selective inhibitor: CTL, Treg, p1 106 T sell response
  • Molecular signature in the tumor
  • WT p110delta, WT 1 10beta+, Mutant p1 10Beta+, PTEN-null, Ibrutinib-resistance, Growth inhibition; suppression of metastesis (p110beta
  • small molecule combination agents: potential aided by selectivity over p110
  • KA2237: clinical Pi3K-p110beta/delta Inhibitor- ATP -comtetitive
  • Doxorubicin -cytotoxic control
  • KA2237 superior activity to Idelasib
  • KA2237 – suppression of micro-metastasis in 4T1 synergenic model
  • Tumor Growth inhibition Pre-Surgery
  • Tumor Re-Growth Inhibition Post-Surgery
  • metastasis post surgery
  • Tumor-free mice post-surgery
  • CHemistry: IHC -pAKT; IHC – FOxp3+
  • KA2237 inhibits HGF-stimulated 4T1 tumor
  • 2004 – Preclinical develpemnt PI3K is reported
  • 2006 First PI#K is enter Clinical Trials
  • Targeting p1110Beta (PIKeCB) mutations in cancer with KA2237
  • DIscovery of the mutations lead drug discovery
  • KA@@#&: Potential in treatment of B-Cell Lymphom AS IN TARGETING IBRUTINIB RESISTENCE
  • GROWTH INHIBITION IN HEMATOLOGICAL CANCERS TUMOE CELL LINE PANEL
  • KA2237 – differentiated from competing Pi3K is Superior efficacy cf. p110delta
  • Combination: Not histone deacetylase but a tubulin deacetylase – Hsp90 ans Hsp70
  • T cell exhausion: Tumor growth inhibition vs Suppression of lung metastasis
  • Tumor BiologyRationale vs Clinical Agents
  • Oncogenic mutants, solid tumor supression magrophage, combination PD-1, CTLA$
  • FDA -approved kinase inhibitors

Summary

  1. phase I clinical study commenced in pathients with B cell Lymphoma
  2. Potential for treatment of solid and hematological malignancies

4:35 InCELL Pulse: A Novel Cellular Target Engagement Assay Platform for Drug Discovery

Treiber_Daniel

Daniel Treiber, Ph.D., Vice President, KINOMEscan, DiscoverX Corporation

InCELL Pulse is a quantitative and rapid method for measuring cellular target engagement potencies for small molecule inhibitors. InCELL Pulse capitalizes on two novel DiscoverX technologies, Enzyme Fragment Complementation (EFC) and Pulse Denaturation, which overcome the limitations of related target engagement methods. Examples across multiple target classes will be described.

  • InCELL Pulse – cellular Target ENgagement Assays
  • cellular thermal stabilization-based approach
  • simple, rapid and generig cellular alternative to CETSa
  • Thermal melting Curves vs Isothermal Inhibitor EC50 curves
  • Pulse Denaturation compound binding, or not binding
  • ABL1 Tyrosine Kinase – dose response curve – allosteric Inhibitor
  • MTH1 Hydrolase: InCELL Pulseassay validated for multiple substrate-competitive inhibitors
  • Validated InCELL Pulse Assays for Diverse Kinases
  • Kinase targets; BRAF, MEC1

Summary

  1. validation across proteins

TTP Labtech4:50 Potential Application of Fluorescence Lifetime Assays to Enable Robust, Rapid Protein Binding Assays

Wylie_Paul

Paul Wylie, Ph.D., Head, Applications, TTP Labtech

Current methods to screen protein binding interactions often have limitations due to the reliance on antibodies, but also interference from fluorescent molecules. Fluorescence lifetime has the potential to overcome these problems through directly labelled proteins and lifetime measurements that are independent of total fluorescence intensity.

  • Protein binding as a target class
  • protein-protein interactions (PPIs)
  1. FRET/HTRF
  2. FP
  3. AlphaScreen

What new in FLT?

  • long lifetime fluorophores, economical reagent platform
  • directly labelled reagents – no antibodies
  • independent of total intensity – reduced interference
  • robustness screen vs nuisance screen – caspase-3
  • productive; reduction false positives: FRET
  • protein-binding assays & FLT formats:
  1. protein – small molecule binding – CECR2
  2. protein – peptide binding: long and sholt lifetime
  3. Site-specific labelling vs Non-selective labelling
  4. Toolbox for PoC
  5. Detection reagents
  6. Further develop technology

5:05 Refreshment Break in the Exhibit Hall with Poster Viewing

 

6:40 End of Day

 

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Milestones in Physiology & Discoveries in Medicine and Genomics: Request for Book Review Writing on Amazon.com


physiology-cover-seriese-vol-3individualsaddlebrown-page2

Milestones in Physiology

Discoveries in Medicine, Genomics and Therapeutics

Patient-centric Perspective 

http://www.amazon.com/dp/B019VH97LU 

2015

 

 

Author, Curator and Editor

Larry H Bernstein, MD, FCAP

Chief Scientific Officer

Leaders in Pharmaceutical Business Intelligence

Larry.bernstein@gmail.com

Preface

Introduction 

Chapter 1: Evolution of the Foundation for Diagnostics and Pharmaceuticals Industries

1.1  Outline of Medical Discoveries between 1880 and 1980

1.2 The History of Infectious Diseases and Epidemiology in the late 19th and 20th Century

1.3 The Classification of Microbiota

1.4 Selected Contributions to Chemistry from 1880 to 1980

1.5 The Evolution of Clinical Chemistry in the 20th Century

1.6 Milestones in the Evolution of Diagnostics in the US HealthCare System: 1920s to Pre-Genomics

 

Chapter 2. The search for the evolution of function of proteins, enzymes and metal catalysts in life processes

2.1 The life and work of Allan Wilson
2.2  The  evolution of myoglobin and hemoglobin
2.3  More complexity in proteins evolution
2.4  Life on earth is traced to oxygen binding
2.5  The colors of life function
2.6  The colors of respiration and electron transport
2.7  Highlights of a green evolution

 

Chapter 3. Evolution of New Relationships in Neuroendocrine States
3.1 Pituitary endocrine axis
3.2 Thyroid function
3.3 Sex hormones
3.4 Adrenal Cortex
3.5 Pancreatic Islets
3.6 Parathyroids
3.7 Gastointestinal hormones
3.8 Endocrine action on midbrain
3.9 Neural activity regulating endocrine response

3.10 Genomic Promise for Neurodegenerative Diseases, Dementias, Autism Spectrum, Schizophrenia, and Serious Depression

 

Chapter 4.  Problems of the Circulation, Altitude, and Immunity

4.1 Innervation of Heart and Heart Rate
4.2 Action of hormones on the circulation
4.3 Allogeneic Transfusion Reactions
4.4 Graft-versus Host reaction
4.5 Unique problems of perinatal period
4.6. High altitude sickness
4.7 Deep water adaptation
4.8 Heart-Lung-and Kidney
4.9 Acute Lung Injury

4.10 Reconstruction of Life Processes requires both Genomics and Metabolomics to explain Phenotypes and Phylogenetics

 

Chapter 5. Problems of Diets and Lifestyle Changes

5.1 Anorexia nervosa
5.2 Voluntary and Involuntary S-insufficiency
5.3 Diarrheas – bacterial and nonbacterial
5.4 Gluten-free diets
5.5 Diet and cholesterol
5.6 Diet and Type 2 diabetes mellitus
5.7 Diet and exercise
5.8 Anxiety and quality of Life
5.9 Nutritional Supplements

 

Chapter 6. Advances in Genomics, Therapeutics and Pharmacogenomics

6.1 Natural Products Chemistry

6.2 The Challenge of Antimicrobial Resistance

6.3 Viruses, Vaccines and immunotherapy

6.4 Genomics and Metabolomics Advances in Cancer

6.5 Proteomics – Protein Interaction

6.6 Pharmacogenomics

6.7 Biomarker Guided Therapy

6.8 The Emergence of a Pharmaceutical Industry in the 20th Century: Diagnostics Industry and Drug Development in the Genomics Era: Mid 80s to Present

6.09 The Union of Biomarkers and Drug Development

6.10 Proteomics and Biomarker Discovery

6.11 Epigenomics and Companion Diagnostics

 

Chapter  7

Integration of Physiology, Genomics and Pharmacotherapy

7.1 Richard Lifton, MD, PhD of Yale University and Howard Hughes Medical Institute: Recipient of 2014 Breakthrough Prizes Awarded in Life Sciences for the Discovery of Genes and Biochemical Mechanisms that cause Hypertension

7.2 Calcium Cycling (ATPase Pump) in Cardiac Gene Therapy: Inhalable Gene Therapy for Pulmonary Arterial Hypertension and Percutaneous Intra-coronary Artery Infusion for Heart Failure: Contributions by Roger J. Hajjar, MD

7.3 Diagnostics and Biomarkers: Novel Genomics Industry Trends vs Present Market Conditions and Historical Scientific Leaders Memoirs

7.4 Synthetic Biology: On Advanced Genome Interpretation for Gene Variants and Pathways: What is the Genetic Base of Atherosclerosis and Loss of Arterial Elasticity with Aging

7.5 Diagnosing Diseases & Gene Therapy: Precision Genome Editing and Cost-effective microRNA Profiling

7.6 Imaging Biomarker for Arterial Stiffness: Pathways in Pharmacotherapy for Hypertension and Hypercholesterolemia Management

7.7 Neuroprotective Therapies: Pharmacogenomics vs Psychotropic drugs and Cholinesterase Inhibitors

7.8 Metabolite Identification Combining Genetic and Metabolic Information: Genetic association links unknown metabolites to functionally related genes

7.9 Preserved vs Reduced Ejection Fraction: Available and Needed Therapies

7.10 Biosimilars: Intellectual Property Creation and Protection by Pioneer and by

7.11 Demonstrate Biosimilarity: New FDA Biosimilar Guidelines

 

Chapter 7.  Biopharma Today

8.1 A Great University engaged in Drug Discovery: University of Pittsburgh

8.2 Introduction – The Evolution of Cancer Therapy and Cancer Research: How We Got Here?

8.3 Predicting Tumor Response, Progression, and Time to Recurrence

8.4 Targeting Untargetable Proto-Oncogenes

8.5 Innovation: Drug Discovery, Medical Devices and Digital Health

8.6 Cardiotoxicity and Cardiomyopathy Related to Drugs Adverse Effects

8.7 Nanotechnology and Ocular Drug Delivery: Part I

8.8 Transdermal drug delivery (TDD) system and nanotechnology: Part II

8.9 The Delicate Connection: IDO (Indolamine 2, 3 dehydrogenase) and Cancer Immunology

8.10 Natural Drug Target Discovery and Translational Medicine in Human Microbiome

8.11 From Genomics of Microorganisms to Translational Medicine

8.12 Confined Indolamine 2, 3 dioxygenase (IDO) Controls the Homeostasis of Immune Responses for Good and Bad

 

Chapter 9. BioPharma – Future Trends

9.1 Artificial Intelligence Versus the Scientist: Who Will Win?

9.2 The Vibrant Philly Biotech Scene: Focus on KannaLife Sciences and the Discipline and Potential of Pharmacognosy

9.3 The Vibrant Philly Biotech Scene: Focus on Computer-Aided Drug Design and Gfree Bio, LLC

9.4 Heroes in Medical Research: The Postdoctoral Fellow

9.5 NIH Considers Guidelines for CAR-T therapy: Report from Recombinant DNA Advisory Committee

9.6 1st Pitch Life Science- Philadelphia- What VCs Really Think of your Pitch

9.7 Multiple Lung Cancer Genomic Projects Suggest New Targets, Research Directions for Non-Small Cell Lung Cancer

9.8 Heroes in Medical Research: Green Fluorescent Protein and the Rough Road in Science

9.9 Issues in Personalized Medicine in Cancer: Intratumor Heterogeneity and Branched Evolution Revealed by Multiregion Sequencing

9.10 The SCID Pig II: Researchers Develop Another SCID Pig, And Another Great Model For Cancer Research

Epilogue

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Signaling through the T Cell Receptor (TCR) Complex and the Co-stimulatory Receptor CD28

Curator: Larry H. Bernstein, MD, FCAP

 

 

New connections: T cell actin dynamics

Fluorescence microscopy is one of the most important tools in cell biology research because it provides spatial and temporal information to investigate regulatory systems inside cells. This technique can generate data in the form of signal intensities at thousands of positions resolved inside individual live cells. However, given extensive cell-to-cell variation, these data cannot be readily assembled into three- or four-dimensional maps of protein concentration that can be compared across different cells and conditions. We have developed a method to enable comparison of imaging data from many cells and applied it to investigate actin dynamics in T cell activation. Antigen recognition in T cells by the T cell receptor (TCR) is amplified by engagement of the costimulatory receptor CD28. We imaged actin and eight core actin regulators to generate over a thousand movies of T cells under conditions in which CD28 was either engaged or blocked in the context of a strong TCR signal. Our computational analysis showed that the primary effect of costimulation blockade was to decrease recruitment of the activator of actin nucleation WAVE2 (Wiskott-Aldrich syndrome protein family verprolin-homologous protein 2) and the actin-severing protein cofilin to F-actin. Reconstitution of WAVE2 and cofilin activity restored the defect in actin signaling dynamics caused by costimulation blockade. Thus, we have developed and validated an approach to quantify protein distributions in time and space for the analysis of complex regulatory systems.

RELATED CONTENT

 

Triple-Color FRET Analysis Reveals Conformational Changes in the WIP-WASp Actin-Regulating Complex

 

RELATED CONTENT

T cell activation by antigens involves the formation of a complex, highly dynamic, yet organized signaling complex at the site of the T cell receptors (TCRs). Srikanth et al. found that the lymphocyte-specific large guanosine triphosphatase of the Rab family CRACR2A-a associated with vesicles near the Golgi in unstimulated mouse and human CD4+ T cells. Upon TCR activation, these vesicles moved to the immunological synapse (the contact region between a T cell and an antigen-presenting cell). The guanine nucleotide exchange factor Vav1 at the TCR complex recruited CRACR2A-a to the complex. Without CRACR2A-a, T cell activation was compromised because of defective calcium and kinase signaling.

More than 60 members of the Rab family of guanosine triphosphatases (GTPases) exist in the human genome. Rab GTPases are small proteins that are primarily involved in the formation, trafficking, and fusion of vesicles. We showed that CRACR2A (Ca2+ release–activated Ca2+ channel regulator 2A) encodes a lymphocyte-specific large Rab GTPase that contains multiple functional domains, including EF-hand motifs, a proline-rich domain (PRD), and a Rab GTPase domain with an unconventional prenylation site. Through experiments involving gene silencing in cells and knockout mice, we demonstrated a role for CRACR2A in the activation of the Ca2+ and c-Jun N-terminal kinase signaling pathways in response to T cell receptor (TCR) stimulation. Vesicles containing this Rab GTPase translocated from near the Golgi to the immunological synapse formed between a T cell and a cognate antigen-presenting cell to activate these signaling pathways. The interaction between the PRD of CRACR2A and the guanidine nucleotide exchange factor Vav1 was required for the accumulation of these vesicles at the immunological synapse. Furthermore, we demonstrated that GTP binding and prenylation of CRACR2A were associated with its localization near the Golgi and its stability. Our findings reveal a previously uncharacterized function of a large Rab GTPase and vesicles near the Golgi in TCR signaling. Other GTPases with similar domain architectures may have similar functions in T cells.

 

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Consuming Risk Free Food & Beverages

Author: Debashree Chakrabarti, MSc., Biological Sciences, UMass Lowell (Expected May 2016)

Leading researchers and medical health professionals have raised their concern about the over all declining status of health and well being world wide. A rising trend in childhood obesity, cardiovascular diseases, clinical depression syndrome in young adults is reason enough to try and broaden the scope of plausible agents which result in people making bad health decisions.  As a witness to the emerging dietary trends adopted by children and young adults, it is natural to question the ethics of processed food and beverages industry. Does it seem reasonable the 2L bottles of soda cost $2 USD? There are more people claiming to not like water since it is flavorless. 100% fresh juices are subject to scrutiny for their lack of adequate fiber content and excess presence of sugars. Products with high fructose corn syrups, added preservatives in processed meat, ‘read to eat’ meals are agreeably cost effective and saves a lot of time, however the over riding damage is in the long run with deficient immune system and gain of unnatural toxins which the body finds hard to eliminate. Another marketing frenzy is visible in the neutraceuticals range of instant energy drinks, protein shakes and over the counter pills. The focus is towards having the visibly attractive, muscular body regardless of the compromised health. The companies do their bit of limiting the usage by adding a precaution statement and dosage remarks on the product labels. This is however not translated as useful information to the young consumers who do not foresee the detrimental outcomes in advance.

As the prices of insurance packages and medical aid is negotiated, the same effort needs invested in the regulation of consumer dietary products. We do not want a ban on Colas however, we do not also need them to be sold at prices cheaper than water. Fresh fruits and vegetables need not be price tagged astronomically driving population to adopt a risk driven lifestyle. Taking initiatives to promote urban farming and local gardens, reaching out to the people about their choices and how it impacts the global financial predicament is a need of the hour. We are ok with the attitude of “Don’t tell me how to live my life” in a world relying heavily on subsidized medicines. This has to change. Subsidized medicine is a privilege and should be benefited to those responsible. Researchers and big pharma companies are not the only stake holders in this fight against an exponentially growing illness of misinformed decisions. People need to be brought in and educated. This includes strong arming anyone who feels they have a right to abuse their health or the health of the world.

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Another paradigm to this discussion is the need for more extensive research hubs world wide and making the accessibility of advanced medicines available to the dense population regions in Asia, Africa and Middle East Arab countries which host the majority of the population and have the least of the resources. We need 100 Massachusetts world wide with cutting edge researchers deep diving and venture capitalists backing them up. A vision for 2050 must encompass every individual being aware of what it takes to damage a human body which is a very robust machine. Eating right and being able to afford health must not be difficult. Choices available in the stores must be rational to the level where the most ignorant of the lot is still consuming risk free substances. Given the fantastic evolutionary armaments we have, it takes a lot to be unwell and yet we seem to making it fairly easy to catch cold. Healthy people translate to healthy economy.

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