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Newly Found Functions of B Cell

Posted in Adaptive Immune Response to Biomaterials and Tissue Repair, Allergy and Infectious Diseases, Autoimmune Inflammatory DIseases, CANCER BIOLOGY & Innovations in Cancer Therapy, Cancer Vaccines: Targeting Cancer Genes for Immunotherapy, Cancer-Immune Interactions, CNS-Immune Interface, combination immunotherapies., Cytokine Receptor Structure, Cytokines, Diagnostic Immunology, Human Immune System in Health and in Disease, Human Naive B Cell Repertoire, Immune Engineering, Immune Modulatory, Immuno-Oncology & Genomics, Immunodiagnostics, Immunology, Immunotherapy, Infectious Disease Immunodiagnostics, Innovation in Immunology Diagnostics, Integrin-targeted Combination Immunotherapy, Metabolic Immuno-Oncology, Modulating Macrophages in Cancer Immunotherapy, Monoclonal Immunotherapy, NK Cell-Based Cancer Immunotherapy, Protection Against Autoimmune Disease, Synergistic Innate and Adaptive Immunotherapy, Synthetic Immunology: Hacking Immune Cells, Tolerance-inducing Autoimmune Disease Therapeutics, Universal Immune Cell Therapies (uICT), tagged Allergy, autoimmunity, B cell receptor, B-cell, Cancer, immune system, immunosuppression on May 23, 2019| Leave a Comment »

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 Role of Exosomes in Metabolic Regulation

Posted in Biological Networks, Chemical Biology and its relations to Metabolic Disease, Exosomes: Natural Carriers for siRNA Delivery, Microfuidics, RNA Biology, tagged alix, annexins, autoimmunity, body fluids, cancer genomics and therapy, caspase-1, cellular immunity, DNA, ESCRT, Exosomes, extracellular vesicles (EVs), flotillin, heat shock proteins, Hsp60, Hsp70, Hsp90, IL18, IL1b, immune cells, immune resistance, Inflammasome, intercellular communication, interleukins, intraluminal vessicles, LRR, metabolic diseases, MicroRNA, microvessicles, miRNA, multiple vesicle bodies (MVBs), myocardial hypertrophy, neurodegenerative diseases, NLRP3, platelets, RNA, Schwann cells, siRNA, tetraspanin on October 8, 2017| Leave a Comment »

The Role of Exosomes in Metabolic Regulation

Author: Larry H. Bernstein, MD, FCAP

On 9/25/2017, Aviva Lev-Ari, PhD, RN commissioned Dr. Larry H. Bernstein to write a short article on the following topic reported on 9/22/2017 in sciencemission.com

We are publishing, below the new article created by Larry H. Bernstein, MD, FCAP.

Background

During the period between 9/2015 and 6/2017 the Team at Leaders in Pharmaceutical Business Intelligence (LPBI) has launched an R&D effort lead by Aviva Lev-Ari, PhD, RN in conjunction with SBH Sciences, Inc. headed by Dr. Raphael Nir.

This effort, also known as, “DrugDiscovery @LPBI Group” has yielded several publications on EXOSOMES on this Open Access Online Scientific Journal. Among them are included the following:

QIAGEN – International Leader in NGS and RNA Sequencing, 10/08/2017

Reporter: Aviva Lev-Ari, PhD, RN

cell-free DNA (cfDNA) tests could become the ultimate “Molecular Stethoscope” that opens up a whole new way of practicing Medicine, 09/08/2017

Reporter: Aviva Lev-Ari, PhD, RN

Detecting Multiple Types of Cancer With a Single Blood Test (Human Exomes Galore), 07/02/2017

Reporter and Curator: Irina Robu, PhD

Exosomes: Natural Carriers for siRNA Delivery, 04/24/2017

Reporter: Aviva Lev-Ari, PhD, RN

One blood sample can be tested for a comprehensive array of cancer cell biomarkers: R&D at WPI, 01/05/2017

Curator: Marzan Khan, B.Sc

SBI’s Exosome Research Technologies, 12/29/2016

Reporter: Aviva Lev-Ari, PhD, RN

A novel 5-gene pancreatic adenocarcinoma classifier: Meta-analysis of transcriptome data – Clinical Genomics Research @BIDMC, 12/28/2016

Curator: Tilda Barliya, PhD

Liquid Biopsy Chip detects an array of metastatic cancer cell markers in blood – R&D @Worcester Polytechnic Institute, Micro and Nanotechnology Lab, 12/28/2016

Reporters: Tilda Barliya, PhD and Aviva Lev-Ari, PhD, RN

Exosomes – History and Promise, 04/28/2016

Reporter: Aviva Lev-Ari, PhD, RN

Exosomes, 11/17/2015

Curator: Larry H. Bernstein, MD, FCAP

Liquid Biopsy Assay May Predict Drug Resistance, 11/16/2015

Curator: Larry H. Bernstein, MD, FCAP

Glypican-1 identifies cancer exosomes, 10/31/2015

Curator: Larry H. Bernstein, MD, FCAP

Circulating Biomarkers World Congress, March 23-24, 2015, Boston: Exosomes, Microvesicles, Circulating DNA, Circulating RNA, Circulating Tumor Cells, Sample Preparation, 03/24/2015

Reporter: Aviva Lev-Ari, PhD, RN

Cambridge Healthtech Institute’s Second Annual Exosomes and Microvesicles as Biomarkers and Diagnostics Conference, March 16-17, 2015 in Cambridge, MA, 03/17, 2015

Reporter: Aviva Lev-Ari, PhD, RN

The newly created think-piece on the relationship between regulatory functions of Exosomes and Metabolic processes is developed conceptually, below.

The Role of Exosomes in Metabolic Regulation

Author: Larry H. Bernstein, MD, FCAP

We have had more than a half century of research into the genetic code and transcription leading to abundant work on RNA and proteomics. However, more recent work in the last two decades has identified RNA interference in siRNA. These molecules may be found in the circulation, but it has been a challenge to find their use in therapeutics. Exosomes were first discovered in the 1980s, but only recently there has been a huge amount of research into their origin, structure and function. Exosomes are 30–120 nm endocytic membrane-bound extracellular vesicles (EVs)(1-23) , and more specifically multiple vesicle bodies (MVBs) by a budding process from invagination of the outer cell membrane that carry microRNA (miRNA), and have structures composed of protein and lipids (1,23-27 ). EVs are the membrane vesicles secreted by eukaryotic cells for intracellular communication by transferring the proteins, lipids, and RNA under various physiologic conditions as well as during the disease stage. EVs also act as a signalosomes in many biological processes. Inward budding of the plasma membrane forms small vesicles that fuse. Intraluminal vesicles (ILVs) are formed by invagination of the limiting endosomal membrane during the maturation process of early endosome.

EVs are the MVBs secreted that serve in intracellular communication by transferring a cargo consisting of proteins, lipids, and RNA under various physiologic conditions (4, 23). Exosome-mediated miRNA transfer between cells is considered to be necessary for intercellular signaling and exosome-associated miRNAs in biofluids (23). Exosomes carry various molecular constituents of their cell of origin, including proteins, lipids, mRNAs, and microRNAs (miRNAs) (. They are released from many cell types, such as dendritic cells (DCs), lymphocytes, platelets, mast cells, epithelial cells, endothelial cells, and neurons, and can be found in most bodily fluids including blood, urine, saliva, amniotic fluid, breast milk, hydrothoracic fluid, and ascitic fluid, as well as in culture medium of most cell types.Exosomes have also been shown to be involved in noncoding RNA surveillance machinery in generating antibody diversity (24). There are also a vast number of long non-coding RNAs (lncRNAs) and enhancer RNAs (eRNAs) that accumulate R-loop structures upon RNA exosome ablation, thereby, resolving deleterious DNA/RNA hybrids arising from active enhancers and distal divergent eRNA-expressing elements (lncRNA-CSR) engaged in long-range DNA interactions (25). RNA exosomes are large multimeric 3′-5′ exo- and endonucleases representing the central RNA 3′-end processing factor and are implicated in processing, quality control, and turnover of both coding and noncoding RNAs. They are large macromolecular cages that channel RNA to the ribonuclease sites (29). A major interest has been developed to characterize of exosomal cargo, which includes numerous non-randomly packed proteins and nucleic acids (1). Moreover, exosomes play an active role in tumorigenesis, metastasis, and response to therapy through the transfer of oncogenes and onco-miRNAs between cancer cells and the tumor stroma. Blood cells and the vascular endothelium is also exosomal shedding, which has significance for cardiovascular, neurologicological disorders, stroke, and antiphospholipid syndrome (1). Dysregulation of microRNAs and the affected pathways is seen in numerous pathologies their expression can reflect molecular processes of tumor onset and progression qualifying microRNAs as potential diagnostic and prognostic biomarkers (30).

Exosomes are secreted by many cells like B lymphocytes and dendritic cells of hematopoietic and non-hematopoietic origin viz. platelets, Schwann cells, neurons, mast cells, cytotoxic T cells, oligodendrocytes, intestinal epithelial cells were also found to be releasing exosomes (4). They are engaged in complex functions like persuading immune response as the exosomes secreted by antigen presenting cells activate T cells (4). They all have a common set of proteins e.g. Rab family of GTPases, Alix and ESCRT (required for transport) protein and they maintain their cytoskeleton dynamics and participate in membrane fusion. However, they are involved in retrovirus disease pathology as a result of recruitment of the host`s endosomal compartments in order to generate viral vesicles, and they can either spread or limit an infection based on the type of pathogen and its target cells (5).

Upon further consideration, it is understandable how this growing biological work on exosomes has enormous significance for laboratory diagnostics (1, 3, 5, 6, 11, 14, 15, 17-20, 23,30-41) . They are released from many cell types, such as dendritic cells (DCs), lymphocytes, platelets, mast cells, epithelial cells, endothelial cells, and neurons, and can be found in most bodily fluids including blood, urine, saliva, amniotic fluid, breast milk, thoracic and abdominal effusions, and ascitic fluid (1). The involvement of exosomes in disease is broad, and includes: cancer, autoimmune and infectious disease, hematologic disorders, neurodegenerative diseases, and cardiovascular disease. Proteins frequently identified in exosomes include membrane transporters and fusion proteins (e.g., GTPases, annexins, and flotillin), heat shock proteins (e.g., HSC70), tetraspanins (e.g., CD9, CD63, and CD81), MVB biogenesis proteins (e.g., alix and TSG101), and lipid-related proteins and phospholipases. The exosomal lipid composition has been thoroughly analyzed in exosomes secreted from several cell types including DCs and mast cells, reticulocytes, and B-lymphocytes (1). Dysregulation of microRNAs of pathways observed in numerous pathologies (5, 10, 12, 21, 27, 35, 37) including cancers (30), particularly, colon, pancreas, breast, liver, brain, lung (2, 6, 17-20, 30, 33-36, 38, 39). Following these considerations, it is important that we characterize the content of exosomal cargo to gain clues to their biogenesis, targeting, and cellular effects which may lead to identification of biomarkers for disease diagnosis, prognosis and response to treatment (42).

We might continue in pursuit of a particular noteworthy exosome, the NLRP3 inflammasome, which is activated by a variety of external or host-derived stimuli, thereby, initiating an inflammatory response through caspase-1 activation, resulting in inflammatory cytokine IL-1b maturation and secretion (43).
Inflammasomes are multi-protein signaling complexes that activate the inflammatory caspases and the maturation of interleukin-1b. The NLRP3 inflammasome is linked with human autoinflammatory and autoimmune diseases (44). This makes the NLRP3 inflammasome a promising target for anti-inflammatory therapies. The NLRP3 inflammasome is activated in response to a variety of signals that indicate tissue damage, metabolic stress, and infection (45). Upon activation, the NLRP3 inflammasome serves as a platform for activation of the cysteine protease caspase-1, which leads to the processing and secretion of the proinflammatory cytokines interleukin-1β (IL-1β) and IL-18. Heritable and acquired inflammatory diseases are both characterized by dysregulation of NLRP3 inflammasome activation (45).
Receptors of innate immunity recognize conserved moieties associated with either cellular damage [danger-associated molecular patterns (DAMPs)] or invading organisms [pathogen-associated molecular patterns (PAMPs)](45). Either chronic stimulation or overwhelming tissue damage is injurious and responsible for the pathology seen in a number of autoinflammatory and autoimmune disorders, such as arthritis and diabetes. The nucleotide-binding domain leucine-rich repeat (LRR)-containing receptors (NLRs) are PRRs are found intracellularly and they share a unique domain architecture. It consists of a central nucleotide binding and oligomerization domain called the NACHT domain that is located between an N-terminal effector domain and a C-terminal LRR domain (45). The NLR family members NLRP1, NLRP3, and NLRC4 are capable of forming multiprotein complexes called inflammasomes when activated.

The (NLRP3) inflammasome is important in chronic airway diseases such as asthma and chronic obstructive pulmonary disease because the activation results, in pro-IL-1β processing and the secretion of the proinflammatory cytokine IL-1β (46). It has been proposed that Activation of the NLRP3 inflammasome by invading pathogens may prove cell type-specific in exacerbations of airway inflammation in asthma (46). First, NLRP3 interacts with the adaptor protein ASC by sensing microbial pathogens and self-danger signals. Then pro-caspase-1 is recruited and the large protein complex called the NLRP3 inflammasome is formed. This is followed by autocleavage and activation of caspase-1, after which pro-IL-1β and pro-IL-18 are converted into their mature forms. Ion fluxes disrupt membrane integrity, and also mitochondrial damage both play key roles in NLRP3 inflammasome activation (47). Depletion of mitochondria as well as inhibitors that block mitochondrial respiration and ROS production prevented NLRP3 inflammasome activation. Futhermore, genetic ablation of VDAC channels (namely VDAC1 and VDAC3) that are located on the mitochondrial outer membrane and that are responsible for exchanging ions and metabolites with the cytoplasm, leads to diminished mitochondrial (mt) ROS production and inhibition of NLRP3 inflammasome activation (47). Inflammasome activation not only occurs in immune cells, primarily macrophages and dendritic cells, but also in kidney cells, specifically the renal tubular epithelium. The NLRP3 inflammasome is probably involved in the pathogenesis of acute kidney injury, chronic kidney disease, diabetic nephropathy and crystal-related nephropathy (48). The inflammasome also plays a role in autoimmune kidney disease. IL-1 blockade and two recently identified specific NLRP3 inflammasome blockers, MCC950 and β-hydroxybutyrate, may prove to have value in the treatment of inflammasome-mediated conditions.

Autophagosomes derived from tumor cells are referred to as defective ribosomal products in blebs (DRibbles). DRibbles mediate tumor regression by stimulating potent T-cell responses and, thus, have been used as therapeutic cancer vaccines in multiple preclinical cancer models (49). It has been found that DRibbles could induce a rapid differentiation of monocytes and DC precursor (pre-DC) cells into functional APCs (49). Consequently, DRibbles could potentially induce strong innate immune responses via multiple pattern recognition receptors. This explains why DRibbles might be excellent antigen carriers to induce adaptive immune responses to both tumor cells and viruses. This suggests that isolated autophagosomes (DRibbles) from antigen donor cells activate inflammasomes by providing the necessary signals required for IL-1β production.

The Hsp90 system is characterized by a cohort of co-chaperones that bind to Hsp90 and affect its function (50). The co-chaperones enable Hsp90 to chaperone structurally and functionally diverse client proteins. Sahasrabudhe et al. (50) show that the nature of the client protein dictates the contribution of a co-chaperone to its maturation. The study reveals the general importance of the cochaperone Sgt1 (50). In addition to Hsp90, we have to consider Hsp60. Adult cardiac myocytes release heat shock protein (HSP)60 in exosomes. Extracellular HSP60, when not in exosomes, causes cardiac myocyte apoptosis via the activation of Toll-like receptor 4. the protein content of cardiac exosomes differed significantly from other types of exosomes in the literature and contained cytosolic, sarcomeric, and mitochondrial proteins (21).

A new Protein Organic Solvent Precipitation (PROSPR) method efficiently isolates the EV repertoire from human biological samples. Proteomic profiling of PROSPR-enriched CNS EVs indicated that > 75 % of the proteins identified matched previously reported exosomal and microvesicle cargoes. In addition lipidomic characterization of enriched CNS vesicles identified previously reported EV-specific lipid families and novel lipid isoforms not previously detected in human EVs. The characterization of these structures from central nervous system (CNS) tissues is relevant to current neuroscience, especially to advance the understanding of neurodegeneration in amyotrophic lateral sclerosis (ALS), Parkinson’s disease (PD) and Alzheimer’s disease (AD)(15). In addition, study of EVs in brain will enable characterization of the degenerative posttranslational modifications (DPMs) occurring in those proteins.
Neurodegenerative disease is characterized by dysregulation because of NLRP3 inflammasome activation. Alzheimer’s disease (AD) and Parkinson’s disease (PD), both neurodegenerative diseases are associated with the NLRP3 inflammasome. PD is characterized by accumulation of Lewy bodies (LB) formed by a-synuclein (aSyn) aggregation. A recent study revealed that aSyn induces synthesis of pro-IL-1b by an interaction with TLR2 and activates NLRP3 inflammasome resulting in caspase-1 activation and IL-1b maturation in human primary monocytes (43). In addition mitophagy downregulates NLRP3 inflammasome activation by eliminating damaged mitochondria, blocking NLRP3 inflammasome activating signals. It is notable that in this aberrant activation mitophagy downregulates NLRP3 inflammasome activation by eliminating damaged mitochondria, blocking NLRP3 inflammasome activating signals (43).

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Beckler MD, Higginbotham JN, Franklin JL,…, Li M, Liebler DC, Coffey RJ. Proteomic analysis of exosomes from mutant KRAS colon cancer cells identifies intercellular transfer of mutant KRAS. Mol. Cell Proteomics. 2013 Feb 12; (2). https://edrn.nci.nih.gov/publications/23161513-proteomic-analysis-of-exosomes
Alvarez-Llamas G, Díaz J, Zubiri I. Proteome of Human Urinary Exosomes in Diabetic Nephropathy. In Biomarkers in Kidney Disease. Vinood B. Patel, Ed. Springer Science 2015; pp 1-21. DOI 10.1007/978-94-007-7743-9_22-1
Simpson RJ, Jensen SS, Lim JW. Proteomic profiling of exosomes: current perspectives. Proteomics. 2008 Oct; 8(19):4083-99. doi: 10.1002/pmic.200800109.
Scheya JKL, Luther M, Rose KL. Proteomics characterization of exosome cargo. Methods 2015 Oct; 87(1): 75-82. https://doi.org/10.1016/j.ymeth.2015.03.018
Kim M-J, Yoon J-H & Ryu J-H. Mitophagy: a balance regulator of NLRP3 inflammasome Activation. BMB Rep. 2016; 49(10): 529-535. https://doi.org/10.5483/BMBRep.2016.49.10.115
Eun-Kyeong Jo, Kim JK, Shin D-M and C Sasakawa. Molecular mechanisms regulating NLRP3 inflammasome activation. Cell Molec Immunol 2016; 13: 148–159. doi:10.1038/cmi.2015.95
Leemans JC, Cassel SL, and Sutterwala FS. Sensing damage by the NLRP3 inflammasome. Immunol Rev. 2011 Sept; 243(1): 152–162. doi:10.1111/j.1600-065X.2011.01043.x.
Hirota JA, Im H, Rahman MM, Rumzhum NN, Manetsch M, Pascoe CD, Bunge K, Alkhouri H, Oliver BG, Ammit AJ. The nucleotide-binding domain and leucine-rich repeat protein-3 inflammasome is not activated in airway smooth muscle upon toll-like receptor-2 ligation. Am J Respir Cell Mol Biol. 2013 Oct; 49(4):517-24. doi: 10.1165/rcmb.2013-0047OC.
Zhong Z, Sanchez-Lopez E, Karin M. Autophagy, NLRP3 inflammasome and auto-inflammatory immune diseases. Clin Exp Rheumatol. 2016 Jul-Aug; 34(4 Suppl 98):12-6. Epub 2016 Jul 21.
Hutton HL, Ooi JD, Holdsworth SR, Kitching AR. The NLRP3 inflammasome in kidney disease and autoimmunity. Nephrology (Carlton). 2016 Sep; 21(9):736-44. doi: 10.1111/nep.12785
Xing Y, Cao R and Hu H-M. TLR and NLRP3 inflammasome-dependent innate immune responses to tumor-derived autophagosomes (DRibbles). Cell Death and Disease (2016) 7, e2322; doi:10.1038/cddis.2016.206
Sahasrabudhe P, Rohrberg J, Biebl MM, Rutz DA, Buchner J. The Plasticity of the Hsp90 Co-chaperone System. Molecular Cell 2017 Sept; 67:947–961. http://dx.doi.org/10.1016/j.molcel.2017.08.004

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Inflammatory Disorders: Articles published @ pharmaceuticalintelligence.com

Posted in Alzheimer's Disease, Autoimmune Inflammatory DIseases, Autophagy, Bacterial Resistance, Cancer and Current Therapeutics, Crohn's disease, Cytokines, Diabetes Mellitus, Disease Biology, Disease Biology, Small Molecules in Development of Therapeutic Drugs, Enzymes and isoenzymes, Etiology, Gastroenterology, Hematology, Human Immune System in Health and in Disease, Inflammasome, Lung and pulmonology, Lymphoma, Metabolism, Metabolomics, Microbiology, Micronutrients, Nephrology, Neurodegenerative Diseases, Neurological Diseases, Nitric Oxide in Health and Disease, Nutrition, Obesity, Protein-energy malnutrition, Proteolysis, Proteomics, Ulcerative Colitis, Viral diseases, Virology, tagged autoimmunity, systemic inflammatory response, T cells on February 28, 2016| Leave a Comment »

Inflammatory Disorders: Articles published @ pharmaceuticalintelligence.com

Curators: Larry H. Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN

This is a compilation of articles on Inflammatory Disorders that were published

@ pharmaceuticalintelligence.com, since 4/2012 to date

There are published works that have not been included. However, there is a substantial amount of material in the following categories:

Proteomics, metabolomics and diabetes

http://pharmaceuticalintelligence.com/2015/11/16/reducing-obesity-related-inflammation/

http://pharmaceuticalintelligence.com/2015/10/25/the-relationship-of-stress-hypermetabolism-to-essential-protein-needs/

http://pharmaceuticalintelligence.com/2015/10/24/the-relationship-of-s-amino-acids-to-marasmic-and-kwashiorkor-pem/

http://pharmaceuticalintelligence.com/2015/10/24/the-significant-burden-of-childhood-malnutrition-and-stunting/

http://pharmaceuticalintelligence.com/2015/04/14/protein-binding-protein-protein-interactions-therapeutic-implications-7-3/

http://pharmaceuticalintelligence.com/2015/03/07/transthyretin-and-the-stressful-condition/

http://pharmaceuticalintelligence.com/2015/02/13/neural-activity-regulating-endocrine-response/

http://pharmaceuticalintelligence.com/2015/01/31/proteomics/

http://pharmaceuticalintelligence.com/2015/01/17/proteins-an-evolutionary-record-of-diversity-and-adaptation/

http://pharmaceuticalintelligence.com/2014/11/01/summary-of-signaling-and-signaling-pathways/

http://pharmaceuticalintelligence.com/2014/10/31/complex-models-of-signaling-therapeutic-implications/

http://pharmaceuticalintelligence.com/2014/10/24/diabetes-mellitus/

http://pharmaceuticalintelligence.com/2014/10/16/metabolomics-summary-and-perspective/

http://pharmaceuticalintelligence.com/2014/10/14/metabolic-reactions-need-just-enough/

http://pharmaceuticalintelligence.com/2014/11/03/introduction-to-protein-synthesis-and-degradation/

http://pharmaceuticalintelligence.com/2015/09/25/proceedings-of-the-nyas/

http://pharmaceuticalintelligence.com/2014/10/31/complex-models-of-signaling-therapeutic-implications/

http://pharmaceuticalintelligence.com/2014/03/21/what-is-the-key-method-to-harness-inflammation-to-close-the-doors-for-many-complex-diseases/

http://pharmaceuticalintelligence.com/2013/03/05/irf-1-deficiency-skews-the-differentiation-of-dendritic-cells/

http://pharmaceuticalintelligence.com/2012/11/26/new-insights-on-no-donors/

http://pharmaceuticalintelligence.com/2012/11/20/the-potential-for-nitric-oxide-donors-in-renal-function-disorders/

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Immune activation, immunity, antibacterial activity

Posted in Biological Networks, Gene Regulation and Evolution, Federal Budget Appropriations, Genome Biology, Health Economics and Outcomes Research, Healthcare costs and reimbursement, Human Immune System in Health and in Disease, Infectious Disease & New Antibiotic Targets, Molecular Genetics & Pharmaceutical, Neutrophilia, Pharmaceutical Analytics, Pharmaceutical Discovery, Pharmaceutical Drug Discovery, Pharmaceutical R&D Investment, Pharmacogenomics, Platelet count disorder, Population Health Management, Genetics & Pharmaceutical, Prescription Drugs Costs, Proteomics, Regulated Clinical Trials: Design, Methods, Components and IRB related issues, Systemic Inflammatory Response Related Disorders, Technology Transfer: Biotech and Pharmaceutical, Translational Effectiveness, Translational Research, Translational Science, tagged 8-OXO dG, antimicrobial therapy, autoimmunity, cGAMP, DAMP, immune activation, innate immunity, microbiota, PAMPs, ribonuclease TREX1 on July 6, 2014| Leave a Comment »

Larry H. Bernstein, MD, FCAP, Curator

http://pharmaceuticalintelligence.com/6/7/2014/Immune activation, immunity, antibacterial activity

This segment is an update on activation of innate immunity, which has had a great amount of basic science resurgence in the last several decades. It also addresses the issue of antibiotic resistance, which shall be covered more fully in later segments. Antimicrobial resistance is a growing threat, and a challenge to the pharmaceutical industry. Moreover, worldwide travel increases the possibility of transfer of strains of virus and microbiota to distant communities.

8-OH-dG: A novel immune activator.

Innate immunity against viral or pathogenic infection involves sensing of non-self-molecules, otherwise known at pathogen-associated molecular patterns (PAMPs). This same sensing mechanism can be applied to damaged self-molecules, which are called damage-associated molecular patterns (DAMPs). One type of molecular pattern, for both groups, is cytosolic or extracellular DNA. However, there is not an extensive amount of research showing specifically what type of DAMP DNA molecule is best at activating this immune sensing response. A recent study investigated the mechanism behind how oxidized DNA from UV damage activates an immune sensing response.

A group of researchers found that, compared to a variety of types of cellular damage, damage from UV irradiation created a strong immune response (type I IFN response), seen across different types of immune regulatory cells. This was compared with freeze/thaw, physical damage and nutritional deprivation, each of which did not produce a noticeable immune response. Additionally, this immune response was seen when DNA was exposed to UV-A and UV-B (the type of radiation produced by our sun) and UV-C radiation.

DNA can be damaged by UV light directly, or through reactive oxygen species (ROS) caused by UV light. A well-known mark of DNA damaged by ROS is the oxidation of guanine to create 8-hydroxyguanine (8-OH-dG). These researchers saw an increase in 8-OH-dG dependant on the level of UV dose, and this also correlated with an increase in immune response; showing that DNA damage created by UV light in the form of 8-OH-dG is sufficient to activate an immune response. This study shows that 8-OH-dG can be classified at a DAMP.

Next, this group wanted to place a mechanism to these observations. They found that the ability of oxidation-damaged DNA to activate an immune response was dependant on cGAS and STING. Free DNA in the cytosol binds cGAS, a cGAMP synthase. This action produces a messenger molecule which proceeds to bind to and activate STING, an endoplasmic reticulum protein. STING activation will ultimately stimulate a type I IFN response.

When a cell’s own DNA is damaged, the cell’s machinery does all it can to repair it. This sometimes involves erasing, or degrading, the DNA that has been damaged. The enzyme, TREX1 exonuclease, has this job in a cell. However, this group found that when DNA was modified with an 8-OH-dG, it was resistant to this degradation by TREX1. This implies that the observed increase in immune response due to the presence of 8-OH-dG occurred because of an accumulation of damaged DNA, because it was not being degraded by TREX1 and could therefore sufficiently activate cGAS and STING.

This type of study has important implications for autoimmune diseases like lupus erythematosus (LE), which is characterized by its abnormally high number of autoantibodies against DNA. It is possible that this uncontrollable immune response is activated by oxidation-damaged DNA. Studies in this area, therefore, hold great importance.

– See more at: http://www.stressmarq.com/Blog/November-2013/8-OH-dG-A-novel-immune-activator.aspx#sthash.CvSdK0H1.dpuf

Oxidative Damage of DNA Confers Resistance to Cytosolic Nuclease TREX1 Degradation and Potentiates STING-Dependent Immune Sensing

Nadine Gehrke, Christina Mertens, Thomas Zillinger, Jörg Wenzel,…,Winfried Barchet

DOI: http://dx.doi.org/10.1016/j.immuni.2013.08.004

Highlights

•UV or ROS damage potentiates immunorecognition of DNA via cGAS and STING
•The oxidation product 8-OHG in DNA is sufficient for enhanced immunorecognition
•Oxidized self-DNA acts as a DAMP and induces skin lesions in lupus-prone mice
•Oxidized DNA is resistant to cytosolic nuclease TREX1-mediated degradation

Summary

Immune sensing of DNA is critical for antiviral immunity but can also trigger autoimmune diseases such as lupus erythematosus (LE). Here we have provided evidence for the involvement of a damage-associated DNA modification in the detection of cytosolic DNA. The oxidized base 8-hydroxyguanosine (8-OHG), a marker of oxidative damage in DNA, potentiated cytosolic immune recognition by decreasing its susceptibility to 3′ repair exonuclease 1 (TREX1)-mediated degradation. Oxidizative modifications arose physiologically in pathogen DNA during lysosomal reactive oxygen species (ROS) exposure, as well as in neutrophil extracellular trap (NET) DNA during the oxidative burst. 8-OHG was also abundant in UV-exposed skin lesions of LE patients and colocalized with type I interferon (IFN). Injection of oxidized DNA in the skin of lupus-prone mice induced lesions that closely matched respective lesions in patients. Thus, oxidized DNA represents a prototypic damage-associated molecular pattern (DAMP) with important implications for infection, sterile inflammation, and autoimmunity.

ribonuclease TREX1 and immunity

Immunity 19 Sep 2013;39(3), p482–495,

New Weapon in Fight Against ‘Superbugs’

Some harmful bacteria are increasingly resistant to treatment with antibiotics. A discovery might be able to help the antibiotics treat the disease.

By ANN LUKITS June 30, 2014 8:47 p.m. ET

Some harmful bacteria are increasingly resistant to treatment with antibiotics. This common fungus found in soil might be able to help the antibiotics combat diseases. Corbis

A soil sample from a national park in eastern Canada has produced a compound that appears to reverse antibiotic resistance in dangerous bacteria.

Scientists at McMaster University in Ontario discovered that the compound almost instantly turned off a gene in several harmful bacteria that makes them highly resistant to treatment with a class of antibiotics used to fight so-called superbug infections. The compound, called aspergillomarasmine A, or AMA, was extracted from a common fungus found in soil and mold.

Antibiotic resistance is a growing public-health threat. Common germs such asEscherichia coli, or E. coli, are becoming harder to treat because they increasingly don’t respond to antibiotics. Some two million people in the U.S. are infected each year by antibiotic-resistant bacteria and 23,000 die as a result, according to the Centers for Disease Control and Prevention. The World Health Organization has called antibiotic resistance a threat to global public health.

The Canadian team was able to disarm a gene—New Delhi Metallo-beta-Lactamase-1, or NDM-1—that has become “public enemy No. 1” since its discovery in 2009, says Gerard Wright, director of McMaster’s Michael G. DeGroote Institute for Infectious Disease Research and lead researcher on the study. The report appears on the cover of this week’s issue of the journal Nature.

“Discovery of a fungus capable of rendering these multidrug-resistant organisms incapable of further infection is huge,” says Irena Kenneley, a microbiologist and infectious disease specialist at Frances Payne Bolton School of Nursing at Cleveland’s Case Western Reserve University. “The availability of more treatment options will ultimately save many more lives,” says Dr. Kenneley, who wasn’t involved in the McMaster research.

The McMaster team plans further experiments to determine the safety and effective dosage of AMA. It could take as long as a decade to complete clinical trials on people with superbug infections, Dr. Wright says.

The researchers found that AMA, extracted from a strain of Aspergillus versicolor and combined with a carbapenem antibiotic, inactivated the NDM-1 gene in three drug-resistant superbugs—Enterobacteriaceae, a group of bacteria that includes E. coli;Acenitobacter, which can cause pneumonia and blood infections; and Pseudomonas, which often infect patients in hospitals and nursing homes. The NDM-1 gene encodes an enzyme that helps bacteria become resistant to antibiotics and that requires zinc to survive. AMA works by removing zinc from the enzyme, freeing the antibiotic to do its job, Dr. Wright says. Although AMA was only tested on carbapenem-resistant bacteria, he expects the compound would have a similar effect when combined with other antibiotics.

AMA was first identified in the 1960s in connection with leaf wilt in plants and later investigated as a potential drug for treating high blood pressure. The compound turned up in Dr. Wright’s lab a few years ago during a random screening of organisms derived from 10,000 soil samples stored at McMaster. The sample that produced AMA was collected by one of Dr. Wright’s graduate students during a visit to a Nova Scotia park. It was the only sample of 500 tested that inhibited NDM-1 in cell cultures.

“It was a lucky hit,” says Dr. Wright. “It tells us that going back to those environmental organisms, where we got antibiotics in the first place, is a really good idea.”

The McMaster team developed a purified form of AMA for experiments on mice injected with a lethal form of drug-resistant pneumonia. Treatment with either AMA or a carbapenem antibiotic alone proved ineffective. But combining the substances resulted in more than 95% of the mice still being alive after five days. The combination was also tested on 229 cell cultures from human patients infected with resistant superbugs. The treatment resensitized 88% of the samples to carbapenem.

Still, bacteria could someday find a way to outwit AMA. “I can’t imagine anything we could make where resistance would never be an issue,” he says. “At the end of the day, this is evolution and you can’t fight evolution.”