1 6009 126 THE ANTI-INFLAMMATORY MEDIATOR, VASOACTIVE INTESTINAL PEPTIDE, MODULATES THE DIFFERENTIATION AND FUNCTION OF TH SUBSETS IN RHEUMATOID ARTHRITIS. GENETIC BACKGROUND, EPIGENETIC MODIFICATIONS, AND ENVIRONMENTAL FACTORS TRIGGER AUTOIMMUNE RESPONSE IN RHEUMATOID ARTHRITIS (RA). SEVERAL PATHOGENIC INFECTIONS HAVE BEEN RELATED TO THE ONSET OF RA AND MAY CAUSE AN INADEQUATE IMMUNOLOGICAL TOLERANCE TOWARDS CRITICAL SELF-ANTIGENS LEADING TO CHRONIC JOINT INFLAMMATION AND AN IMBALANCE BETWEEN DIFFERENT T HELPER (TH) SUBSETS. VASOACTIVE INTESTINAL PEPTIDE (VIP) IS A MEDIATOR THAT MODULATES ALL THE STAGES COMPRISED BETWEEN THE ARRIVAL OF PATHOGENS AND TH CELL DIFFERENTIATION IN RA THROUGH ITS KNOWN ANTI-INFLAMMATORY AND IMMUNOMODULATORY ACTIONS. THIS "NEUROIMMUNOPEPTIDE" MODULATES THE PATHOGENIC ACTIVITY OF DIVERSE CELL SUBPOPULATIONS INVOLVED IN RA AS LYMPHOCYTES, FIBROBLAST-LIKE SYNOVIOCYTES (FLS), OR MACROPHAGES. IN ADDITION, VIP DECREASES THE EXPRESSION OF PATTERN RECOGNITION RECEPTOR (PRR) SUCH AS TOLL-LIKE RECEPTORS (TLRS) IN FLS FROM RA PATIENTS. THESE RECEPTORS ACT AS SENSORS OF PATHOGEN-ASSOCIATED MOLECULAR PATTERN (PAMP) AND DAMAGE-ASSOCIATED MOLECULAR PATTERN (DAMP) CONNECTING THE INNATE AND ADAPTIVE IMMUNE SYSTEM. MOREOVER, VIP MODULATES THE IMBALANCE BETWEEN TH SUBSETS IN RA, DECREASING PATHOGENIC TH1 AND TH17 SUBSETS AND FAVORING TH2 OR TREG PROFILE DURING THE DIFFERENTIATION/POLARIZATION OF NAIVE OR MEMORY TH CELLS. FINALLY, VIP REGULATES THE PLASTICITY BETWEEN THESES SUBSETS. IN THIS REVIEW, WE PROVIDE AN OVERVIEW OF VIP EFFECTS ON THE AFOREMENTIONED FEATURES OF RA PATHOLOGY. 2018 2 2008 33 EPIGENETIC BASIS FOR MONOCYTE DYSFUNCTION IN PATIENTS WITH SEVERE ALCOHOLIC HEPATITIS. BACKGROUND & AIMS: SEVERE FORMS OF ALCOHOL-RELATED LIVER DISEASE ARE ASSOCIATED WITH INCREASED SUSCEPTIBILITY TO INFECTIONS WHICH ARE ASSOCIATED WITH POOR PROGNOSIS. THE CELLULAR AND MOLECULAR MECHANISMS RESPONSIBLE FOR THIS ALTERED HOST DEFENSE ARE INCOMPLETELY UNDERSTOOD. METHODS: WE PERFORMED WHOLE BLOOD PHENOTYPIC ANALYSIS AND EX VIVO STIMULATION WITH VARIOUS PATHOGEN-ASSOCIATED MOLECULAR PATTERNS (PAMPS). WE INCLUDED 34 PATIENTS WITH ALCOHOL-RELATED CIRRHOSIS (18 OF WHOM HAD BIOPSY-PROVEN SEVERE ALCOHOLIC HEPATITIS [SAH]), 12 HEALTHY CONTROLS AND 11 PATIENTS WITH CHRONIC ALCOHOL CONSUMPTION WITHOUT SIGNIFICANT LIVER DISEASE. WE ALSO EVALUATED THE TRANSCRIPTOMIC (RNA-SEQ) AND CHROMATIN ACCESSIBILITY (ATAC-SEQ) PROFILES OF CD14(+) MONOCYTES FROM A SUBSET OF PATIENTS. RESULTS: CIRCULATING MONOCYTES AND CONVENTIONAL DENDRITIC CELLS (DCS) FROM PATIENTS WITH SAH DISPLAYED COMPLEX ALTERATIONS CHARACTERIZED BY INCREASED EXPRESSION OF BOTH ACTIVATING AND INHIBITORY SURFACE MARKERS AND AN IMPAIRED PRO-INFLAMMATORY RESPONSE UPON STIMULATION WITH PAMPS REPRESENTATIVE OF GRAM-NEGATIVE BACTERIA (LIPOPOLYSACCHARIDE, PAM3CSK4) OR FUNGAL PATHOGENS (ZYMOSAN). THEIR DECREASED ABILITY TO PRODUCE MORE THAN 1 CYTOKINE (POLYFUNCTIONALITY) UPON PAMP STIMULATION CORRELATED WITH THE RISK OF DEVELOPING INFECTION AT 28 DAYS OR MORTALITY AT 90 DAYS. THE PRESENCE OF ACUTE-ON-CHRONIC LIVER FAILURE IN PATIENTS WITH SAH DID NOT SIGNIFICANTLY MODIFY THE IMMUNE PROFILE OF MONOCYTES AND DCS. MOREOVER, CD14(+) MONOCYTES OF PATIENTS WITH SAH DISPLAYED ALTERED TRANSCRIPTIONAL AND EPIGENOMIC PROFILES CHARACTERIZED BY DOWNREGULATION OF KEY INNATE IMMUNE AND METABOLIC PATHWAYS AND UPREGULATION OF IMPORTANT IMMUNOMODULATORY FACTORS. CONCLUSIONS: IN PATIENTS WITH SAH, THE ALTERED TRANSCRIPTIONAL PROGRAM AND FUNCTIONAL PROPERTIES OF MONOCYTES THAT CONTRIBUTE TO PATIENTS' SUSCEPTIBILITY TO INFECTION HAVE STRONG EPIGENETIC DETERMINANTS. LAY SUMMARY: PATIENTS WITH SEVERE ALCOHOLIC HEPATITIS ARE AT INCREASED RISK OF INFECTIONS, WHICH CONTRIBUTE TO THE POOR PROGNOSIS ASSOCIATED WITH THE DISEASE. HEREIN, WE SHOW THAT EPIGENETIC DETERMINANTS UNDERLY THE IMMUNE CELL DYSFUNCTION AND INAPPROPRIATE RESPONSES TO PATHOGENS THAT ARE ASSOCIATED WITH SEVERE ALCOHOLIC HEPATITIS. 2020 3 4305 23 MICRORNA-27A-3P ENHANCES THE INFLAMMATORY PHENOTYPE OF JUVENILE IDIOPATHIC ARTHRITIS FIBROBLAST-LIKE SYNOVIOCYTES. BACKGROUND: JUVENILE IDIOPATHIC ARTHRITIS (JIA) IS THE MOST PREVALENT CHRONIC PEDIATRIC RHEUMATIC DISORDER. IN JOINTS OF JIA PATIENTS, AGGRESSIVE PHENOTYPIC CHANGES IN FIBROBLAST-LIKE SYNOVIOCYTES (FLS) OF THE SYNOVIAL LINING PLAY A KEY ROLE IN INFLAMMATION. MICRORNAS ARE DYSREGULATED IN RHEUMATOID ARTHRITIS AND JIA, INCLUDING MIR-27A-3P. HOWEVER, IT IS NOT UNDERSTOOD IF MIR-27A-3P, ENRICHED IN JIA SYNOVIAL FLUID (SF) AND LEUKOCYTES, ALTERS FLS FUNCTION. METHODS: PRIMARY JIA FLS CELLS WERE TRANSFECTED WITH A MIR-27A-3P MIMIC OR A NEGATIVE CONTROL MICRORNA (MIR-NC) AND STIMULATED WITH POOLED JIA SF OR INFLAMMATORY CYTOKINES. VIABILITY AND APOPTOSIS WERE ANALYZED BY FLOW CYTOMETRY. PROLIFERATION WAS EVALUATED USING A (3)H-THYMIDINE INCORPORATION ASSAY. CYTOKINE PRODUCTION WAS ASSESSED BY QPCR AND ELISA. EXPRESSION OF TGF-BETA PATHWAY GENES WAS DETERMINED USING A QPCR ARRAY. RESULTS: MIR-27A-3P WAS CONSTITUTIVELY EXPRESSED IN FLS. OVEREXPRESSION OF MIR-27A-3P CAUSED INCREASED INTERLEUKIN-8 SECRETION IN RESTING FLS, AND INTERLEUKIN-6 WAS ELEVATED IN SF-ACTIVATED FLS COMPARED TO MIR-NC. FURTHERMORE, STIMULATION WITH PRO-INFLAMMATORY CYTOKINES AUGMENTED FLS PROLIFERATION IN MIR-27A-3P-TRANSFECTED FLS RELATIVE TO MIR-NC. EXPRESSION OF MULTIPLE TGF-BETA PATHWAY GENES WAS MODULATED BY OVEREXPRESSION OF MIR-27A-3P. CONCLUSIONS: MIR-27A-3P SIGNIFICANTLY CONTRIBUTES TO FLS PROLIFERATION AND CYTOKINE PRODUCTION, MAKING IT A POTENTIAL CANDIDATE FOR EPIGENETIC THERAPY THAT TARGETS FLS IN ARTHRITIS. 2023 4 6891 28 [SIGNAL RECEPTORS OF CONGENITAL IMMUNITY: A NEW MOLECULAR TARGET FOR DIAGNOSTICS AND TREATMENT OF INFLAMMATORY DISEASES]. THE DISCOVERY OF SIGNAL RECEPTORS OF CONGENITAL IMMUNITY (SIGNAL PRR) NOT ONLY PROVIDED A NOVEL VIEW OF BASIC ASPECTS OF PATHOGENESIS OF CHRONIC INFLAMMATORY DISEASES BUT ALSO CREATED A BASIS FOR THE DEVELOPMENT OF ADDITIONAL DIAGNOSTIC CRITERIA FOR THESE PATHOLOGIES AND NEW PHARMACEUTICALS FOR THEIR TREATMENT. REDUCED EXPRESSION AND FUNCTION OF PRR DUE TO MUTATIONS/POLYMORPHISMS OR EPIGENETIC DISTURBANCES OF REGULATION CAN BE REGARDED AS IMMUNODEFICIENT CONDITIONS MANIFEST AS SEVERE INFECTIOUS INFLAMMATORY DISEASES. IN CONTRAST, EXCESSIVE EXPRESSION AND ACTIVATION OF PRR AS A RULE LEADS TO CHRONIC AUTOINFLAMMATORY, AUTOIMMUNE, AND ATOPIC DISEASES INVOLVING ADAPTIVE IMMUNITY AND AGGRESSION AGAINST OWN TISSUES AND CELLS. ASSESSMENT OF CERTAIN MUTATIONS IN PRR GENES, THEIR EXPRESSION AND ACTIVATION PROVIDES A POWERFUL TOOL FOR IN-DEPTH DIAGNOSTICS OF INFLAMMATORY DISEASES. SIMULTANEOUSLY, NEW LINES OF IMMUNOSTIMULATING AND ANTI-INFLAMMATORY THERAPY ARE DEVELOPED BASED ON THE KNOWLEDGE OF MOLECULAR PHYSIOLOGY OF PRR WITH THE USE OF SYNTHETIC AGONISTS AND ANTAGONISTS OF SIGNAL PRR. 2011 5 6476 33 TOLL-LIKE RECEPTORS, INFECTIONS, AND RHEUMATOID ARTHRITIS. TOLL-LIKE RECEPTORS (TLR) THAT BELONG TO THE GROUP OF PROTEIN RECOGNITION RECEPTOR (PPR) PROVIDE AN INNATE IMMUNE RESPONSE FOLLOWING THE SENSING OF CONSERVED PATHOGEN-ASSOCIATED MICROBIAL PATTERNS (PAMPS) AND CHANGES IN DANGER-ASSOCIATED MOLECULAR PATTERNS (DAMPS) THAT ARE GENERATED AS A CONSEQUENCE OF CELLULAR INJURY. ANALYSIS OF THE TLR PATHWAY HAS MOREOVER OFFERED NEW INSIGHTS INTO THE PATHOGENESIS OF RHEUMATOID ARTHRITIS (RA). INDEED, A DYSFUNCTIONAL TLR-MEDIATED RESPONSE CHARACTERIZES RA PATIENTS AND PARTICIPATES IN ESTABLISHMENT OF A CHRONIC INFLAMMATORY STATE. SUCH AN INAPPROPRIATE TLR RESPONSE HAS BEEN ATTRIBUTED (I) TO THE REPORT OF IMPORTANT ALTERATIONS IN THE MICROBIOTA AND ABNORMAL RESPONSES TO INFECTIOUS AGENTS AS PART OF RA; (II) TO THE ABNORMAL PRESENCE OF TLR-LIGANDS IN THE SERUM AND SYNOVIAL FLUID OF RA PATIENTS; (III) TO THE OVEREXPRESSION OF TLR MOLECULES; (IV) TO THE PRODUCTION OF A LARGE PANEL OF PRO-INFLAMMATORY CYTOKINES DOWNSTREAM OF THE TLR PATHWAY; AND (V) TO GENETIC VARIANTS AND EPIGENETIC FACTORS IN SUSCEPTIBLE RA PATIENTS PROMOTING A HYPER TLR RESPONSE. AS A CONSEQUENCE, THE DEVELOPMENT OF PROMISING THERAPEUTIC STRATEGIES TARGETING TLRS FOR THE TREATMENT AND PREVENTION OF RA IS EMERGING. 2020 6 4041 34 MACROPHAGE PLASTICITY IN DUCHENNE MUSCULAR DYSTROPHY: A NEXUS OF PATHOLOGICAL REMODELLING WITH THERAPEUTIC IMPLICATIONS. DUCHENNE MUSCULAR DYSTROPHY (DMD) IS CHARACTERIZED BY CHRONIC SKELETAL MUSCLE NECROSIS, LEADING TO MUSCLE REGENERATION FAILURE AND FIBROSIS. ALTHOUGH MACROPHAGES (MPS) ARE NORMALLY ESSENTIAL FOR MUSCLE REGENERATION, DYSREGULATED MP FUNCTION PROMOTES PATHOLOGICAL MUSCLE REMODELLING. INFILTRATING MPS CAN BE PREDOMINANTLY PRO-INFLAMMATORY (M1 BIASED), ANTI-INFLAMMATORY (M2 BIASED) OR OF A MIXED PHENOTYPE AND CAN ORIGINATE FROM THE ADULT BONE MARROW (MONOCYTE DEPENDENT) OR EMBRYONIC PRECURSORS (MONOCYTE INDEPENDENT). IN MDX MICE (GENETIC MODEL OF DMD) LACKING EITHER TOLL-LIKE RECEPTOR (TLR) 2 OR TLR4, IT IS FOUND THAT MP INFILTRATION OF DYSTROPHIC MUSCLE IS SIGNIFICANTLY REDUCED AND THAT THE MP PHENOTYPE IS SHIFTED TOWARD A MORE ANTI-INFLAMMATORY PROFILE. THIS IS ACCOMPANIED BY SIGNIFICANT IMPROVEMENTS IN MUSCLE HISTOLOGY AND FORCE PRODUCTION. LACK OF THE CHEMOKINE RECEPTOR CCR2, WHICH IMPEDES MONOCYTE RELEASE FROM THE BONE MARROW, LEADS TO SIMILAR BENEFICIAL EFFECTS IN MDX MICE. EVIDENCE WAS ALSO FOUND FOR TLR4-REGULATED INDUCTION OF TRAINED INNATE IMMUNITY IN MPS CULTURED FROM THE BONE MARROW OF MDX MICE BEFORE THEIR ENTRY INTO THE MUSCLE. THESE MPS EXHIBIT EPIGENETIC AND METABOLIC ALTERATIONS, ACCOMPANIED BY NON-SPECIFIC HYPER-RESPONSIVENESS TO MULTIPLE STIMULI, WHICH IS MANIFESTED BY POTENTIATED UPREGULATION OF BOTH PRO- AND ANTI-INFLAMMATORY GENES. IN SUMMARY, EXAGGERATED RECRUITMENT OF MONOCYTE-DERIVED MPS AND SIGNS OF TRAINED INNATE IMMUNITY AT THE LEVEL OF THE BONE MARROW ARE FEATURES OF THE IMMUNOPHENOTYPE ASSOCIATED WITH DYSTROPHIC MUSCLE DISEASE. THESE PHENOMENA ARE REGULATED BY TOLL-LIKE RECEPTORS THAT BIND ENDOGENOUS DAMAGE-ASSOCIATED MOLECULAR PATTERN (DAMP) MOLECULES, SUGGESTING THAT DAMP RELEASE FROM DYSTROPHIC MUSCLES MODULATES MP PLASTICITY AT THE BONE MARROW LEVEL THROUGH TOLL-LIKE RECEPTOR-DRIVEN MECHANISMS. 2022 7 5417 37 REGULATION OF DNA METHYLATION IN RHEUMATOID ARTHRITIS SYNOVIOCYTES. RHEUMATOID ARTHRITIS (RA) IS A CHRONIC INFLAMMATORY DISEASE IN WHICH FIBROBLAST-LIKE SYNOVIOCYTES (FLS) EXHIBIT AN AGGRESSIVE PHENOTYPE. ALTHOUGH THE MECHANISMS RESPONSIBLE ARE NOT WELL DEFINED, EPIGENETIC DETERMINANTS SUCH AS DNA METHYLATION MIGHT CONTRIBUTE. DNA METHYLTRANSFERASES (DNMTS) ARE CRITICAL ENZYMES THAT ESTABLISH AND MAINTAIN DNA METHYLATION. WE EVALUATED WHETHER PROINFLAMMATORY CYTOKINES MIGHT CONTRIBUTE TO DIFFERENTIAL DNA METHYLATION PREVIOUSLY DESCRIBED IN RA FLS THROUGH ALTERED DNMT EXPRESSION. FLS WERE OBTAINED FROM RA AND OSTEOARTHRITIS (OA) SYNOVIUM AT THE TIME OF TOTAL JOINT REPLACEMENT. GENE EXPRESSION WAS DETERMINED BY QUANTITATIVE REAL-TIME PCR AND PROTEIN EXPRESSION BY WESTERN BLOT ANALYSIS. DNMT ACTIVITY WAS MEASURED WITH A FUNCTIONAL ASSAY, AND GLOBAL METHYLATION WAS DETERMINED BY AN IMMUNOASSAY THAT DETECTS METHYLCYTOSINE. RESTING EXPRESSION OF DNMT1, -3A, AND -3B MRNA WERE SIMILAR IN RA AND OA FLS. WESTERN BLOT SHOWED ABUNDANT DNMT1 AND DNMT3A PROTEIN. EXPOSURE TO IL-1 DECREASED DNMT1 AND DNMT3A MRNA EXPRESSION IN FLS. DOSE RESPONSES DEMONSTRATED DECREASED DNMT EXPRESSION AT CONCENTRATIONS AS LOW AS 1 PG/ML OF IL-1. DNMT MRNA LEVELS DECREASED RAPIDLY, WITH SIGNIFICANT SUPPRESSION AFTER 2-8 H OF IL-1 STIMULATION. IL-1 STIMULATION OF OA FLS DID NOT AFFECT METHYLATION OF LINE1 SITES BUT LED TO DEMETHYLATION OF A CHI3L1 LOCUS THAT IS HYPOMETHYLATED IN RA FLS. CHRONIC IL-1 STIMULATION ALSO MIMICKED THE EFFECT OF A DNMT INHIBITOR ON FLS GENE EXPRESSION. EXPOSURE TO PROINFLAMMATORY MEDIATORS REVERSIBLY ALTERS DNA METHYLATION IN FLS BY DECREASING DNMT EXPRESSION AND FUNCTION. THESE DATA SUGGEST THAT IL-1 CAN POTENTIALLY IMPRINT CELLS IN CHRONIC INFLAMMATORY DISEASES. 2013 8 3789 34 INTERLEUKIN 17 CONTRIBUTES TO THE CHRONICITY OF INFLAMMATORY DISEASES SUCH AS RHEUMATOID ARTHRITIS. RHEUMATOID ARTHRITIS (RA) IS A CHRONIC INFLAMMATORY DISEASE LEADING TO JOINT DESTRUCTION AND BONE RESORPTION. THE PROINFLAMMATORY CYTOKINE INTERLEUKIN 17 (IL-17), PRIMARILY PRODUCED BY TH17 CELLS, HAS BEEN SHOWN TO BE INVOLVED IN ALL STAGES OF THE DISEASE AND TO BE AN IMPORTANT CONTRIBUTOR OF RA CHRONICITY. THREE MAJOR PROCESSES DRIVE THE IL-17-MEDIATED CHRONICITY. SEVERAL EPIGENETIC EVENTS, ENHANCED IN RA PATIENTS, LEAD TO THE INCREASED PRODUCTION OF IL-17 BY TH17 CELLS. IL-17 THEN INDUCES THE PRODUCTION OF SEVERAL INFLAMMATORY MEDIATORS IN THE DISEASED SYNOVIUM, WHICH ARE FURTHER SYNERGISTICALLY ENHANCED VIA COMBINATIONS OF IL-17 WITH OTHER CYTOKINES. IL-17 ALSO PROMOTES THE SURVIVAL OF BOTH THE SYNOVIOCYTES AND INFLAMMATORY CELLS AND PROMOTES THE MATURATION OF THESE IMMUNE CELLS. THIS LEADS TO AN INCREASED NUMBER OF SYNOVIOCYTES AND INFLAMMATORY CELLS IN THE SYNOVIAL FLUID AND IN THE SYNOVIUM LEADING TO THE HYPERPLASIA AND EXACERBATED INFLAMMATION OBSERVED IN JOINTS OF RA PATIENTS. FURTHERMORE, THESE IL-17-DRIVEN EVENTS INITIATE SEVERAL FEEDBACK-LOOP MECHANISMS LEADING TO INCREASED EXPANSION OF TH17 CELLS AND THEREBY INCREASED PRODUCTION OF IL-17. IN THIS REVIEW, WE AIM TO DEPICT A COMPLETE PICTURE OF THE IL-17-DRIVEN VICIOUS CIRCLE LEADING TO RA CHRONICITY AND TO PINPOINT THE KEY ASPECTS THAT REQUIRE FURTHER EXPLORATION. 2014 9 5507 30 RHEUMATOID ARTHRITIS PROGRESSION MEDIATED BY ACTIVATED SYNOVIAL FIBROBLASTS. RHEUMATOID ARTHRITIS (RA) IS A CHRONIC INFLAMMATORY DISEASE CHARACTERIZED BY SYNOVIAL HYPERPLASIA AND PROGRESSIVE JOINT DESTRUCTION. RHEUMATOID ARTHRITIS SYNOVIAL FIBROBLASTS (RASFS) ARE LEADING CELLS IN JOINT EROSION AND CONTRIBUTE ACTIVELY TO INFLAMMATION. RASFS SHOW AN ACTIVATED PHENOTYPE THAT IS INDEPENDENT OF THE INFLAMMATORY ENVIRONMENT AND REQUIRES THE COMBINATION OF SEVERAL FACTORS. ALTHOUGH NEW ASPECTS REGARDING RASF ACTIVATION VIA MATRIX DEGRADATION PRODUCTS, EPIGENETIC MODIFICATIONS, INFLAMMATORY FACTORS, TOLL-LIKE RECEPTOR (TLR) ACTIVATION AND OTHERS HAVE RECENTLY BEEN UNCOVERED, THE PRIMARY PATHOPHYSIOLOGICAL PROCESSES IN EARLY ARTHRITIS LEADING TO PERMANENT ACTIVATION ARE MOSTLY UNKNOWN. HERE, WE REVIEW NEW FINDINGS REGARDING RASF ACTIVATION AND THEIR ALTERED BEHAVIOR THAT CONTRIBUTE TO MATRIX DESTRUCTION AND INFLAMMATION AS WELL AS THEIR POTENTIAL TO SPREAD RA. 2010 10 3701 33 INFLAMMATORY RESPONSE TO REGULATED CELL DEATH IN GOUT AND ITS FUNCTIONAL IMPLICATIONS. GOUT, A CHRONIC INFLAMMATORY ARTHRITIS DISEASE, IS CHARACTERIZED BY HYPERURICEMIA AND CAUSED BY INTERACTIONS BETWEEN GENETIC, EPIGENETIC, AND METABOLIC FACTORS. ACUTE GOUT SYMPTOMS ARE TRIGGERED BY THE INFLAMMATORY RESPONSE TO MONOSODIUM URATE CRYSTALS, WHICH IS MEDIATED BY THE INNATE IMMUNE SYSTEM AND IMMUNE CELLS (E.G., MACROPHAGES AND NEUTROPHILS), THE NACHT, LRR, AND PYD DOMAINS-CONTAINING PROTEIN 3 (NLRP3) INFLAMMASOME ACTIVATION, AND PRO-INFLAMMATORY CYTOKINE (E.G., IL-1BETA) RELEASE. RECENT STUDIES HAVE INDICATED THAT THE MULTIPLE PROGRAMMED CELL DEATH PATHWAYS INVOLVED IN THE INFLAMMATORY RESPONSE INCLUDE PYROPTOSIS, NETOSIS, NECROPTOSIS, AND APOPTOSIS, WHICH INITIATE INFLAMMATORY REACTIONS. IN THIS REVIEW, WE EXPLORE THE CORRELATION AND INTERACTIONS AMONG THESE FACTORS AND THEIR ROLES IN THE PATHOGENESIS OF GOUT TO PROVIDE FUTURE RESEARCH DIRECTIONS AND POSSIBILITIES FOR IDENTIFYING POTENTIAL NOVEL THERAPEUTIC TARGETS AND ENHANCING OUR UNDERSTANDING OF GOUT PATHOGENESIS. 2022 11 4412 33 MOLECULAR AND CELLULAR BASIS OF RHEUMATOID JOINT DESTRUCTION. RHEUMATOID ARTHRITIS (RA) IS A CHRONIC INFLAMMATORY DISEASE ASSOCIATED WITH JOINT DESTRUCTION. SYNOVIAL FIBROBLASTS ARE KEY PLAYERS IN THIS PATHOLOGICAL PROCESS. THEY FAVORISE A PRO-INFLAMMATORY ENVIRONMENT IN THE SYNOVIAL TISSUE, INTERACT WITH THE IMMUNE SYSTEM AND REGULATE THE DIFFERENTIATION OF MONOCYTES INTO OSTEOCLASTS. SYNOVIAL HYPERPLASIA IS ANOTHER CHARACTERISTIC OF RA, REFLECTING NOT ONLY AN IMBALANCE BETWEEN PROLIFERATION AND APOPTOSIS, BUT ALSO THE MIGRATION OF CELLS INTO THE SYNOVIAL TISSUE. GENE TRANSFER EXPERIMENTS HAVE BEEN USED AS IMPORTANT TOOLS FOR THE UNDERSTANDING OF MOLECULAR AND CELLULAR CHANGES THAT CHARACTERIZE THE ACTIVATED RA SYNOVIAL FIBROBLASTS. ACTIVATED SYNOVIAL FIBROBLASTS CAN INVADE CARTILAGE AND BONE. SYNOVIAL ACTIVATION IS DRIVEN BY CYTOKINES, SUCH AS TNFALPHA AND IL-1, AS WELL AS IL-15, 16, 17, 18, 22, 23, BUT ALSO BY CYTOKINE-INDEPENDENT MECHANISMS THAT INVOLVE THE INNATE IMMUNE SYSTEM (I.E. TLRS), A UNIQUE COMMUNICATION NETWORK OF MICROPARTICLES AND EPIGENETIC CHANGES (E.G. L1 RETROELEMENTS). 2006 12 1637 37 DOES DYSREGULATION OF KEY EPIGENETIC AND BIOCHEMICAL PATHWAYS OCCUR IN POSTULATED VASOACTIVE NEUROPEPTIDE AUTOIMMUNE DISORDERS? AUTOIMMUNE DYSFUNCTION OF CERTAIN VASOACTIVE NEUROPEPTIDES (VNS) HAS BEEN POSTULATED AS A CONTRIBUTING CAUSE OF SUDDEN INFANT DEATH SYNDROME (SIDS), CHRONIC FATIGUE SYNDROME (CFS), GULF WAR SYNDROME (GWS) AND OTHER FATIGUE-RELATED DISORDERS. THIS FAMILY OF VNS INCLUDES PITUITARY ADENYLATE CYCLASE ACTIVATING POLYPEPTIDE (PACAP), VASOACTIVE INTESTINAL PEPTIDE (VIP) AND CALCITONIN GENE RELATED PEPTIDE (CGRP). THE POSTULATED MECHANISM IS COMPROMISE OF ADENYLATE CYCLASE ACTIVATION, A VITAL AND UNIQUE STEP IN CYCLIC AMP PRODUCTION FROM ATP, THROUGH AUTOIMMUNE DYSFUNCTION OF VNS, THEIR RECEPTORS OR THEIR GENES POSSIBLY INVOLVING CYTOSINE-PHOSPHATE-GUANINE (CPG) FRAGMENTS. CPG FRAGMENTS ARE IMMUNOMODULATORY DINUCLEOTIDES SERVING AS 'FRIEND OR FOE' RECOGNITION SYSTEMS TO DIFFERENTIATE BACTERIAL AND VIRAL (HYPOMETHYLATED CPG) FROM MAMMALIAN (METHYLATED CPG) DNA. HOWEVER HYPOMETHYLATION DISORDERS AFFECTING THESE FRAGMENTS IN MAMMALS MAY CONVERT THEM TO DYSFUNCTIONAL STATES BY PROMOTING AUTOIMMUNE INFLAMMATORY REACTIONS. EPIGENETIC MECHANISMS ACTING ON GENE PROMOTER REGIONS MAY CONTRIBUTE TO THE DEVELOPMENT OF VN AUTOIMMUNE FATIGUE-RELATED DISORDERS THROUGH CPG FRAGMENTS LOCATED IN VITAL SEGMENTS OF VN/RECEPTOR GENES BY CAUSING SIGNALLING DEFECTS WITH PROFOUND IMPLICATIONS FOR VN FUNCTION. NEUROTRANSMITTER DYSFUNCTION PARTICULARLY GLUTAMATERGIC TRANSMISSION COULD ALSO RESULT WITH DISRUPTION OF NEURONAL CELLULAR BIOCHEMICAL FUNCTIONS SUCH AS AMMONIA REGULATION. ENDOSOMAL ACIDITY AND MITOCHONDRIAL MEMBRANE POTENTIAL MODIFIERS SUCH AS CHLOROQUINE, TOGETHER WITH IMMUNOREGULATORY THERAPIES, MAY HAVE THERAPEUTIC IMPLICATIONS IN PROTECTING AGAINST THESE APPARENT AUTOIMMUNE DISORDERS. THIS PAPER EXAMINES SPECIFIC EPIGENETIC AND BIOCHEMICAL MECHANISMS POSSIBLY MEDIATED BY VN OR RECEPTOR GENES RESULTING IN POSTULATED VN AUTOIMMUNE FATIGUE-RELATED DISORDERS. THESE MECHANISMS MAY HAVE IMPLICATIONS FOR TREATMENT AND PREVENTION OPTIONS FOR VN AUTOIMMUNE DISORDERS. VN AUTOIMMUNE PROCESSES HAVE IMPLICATIONS FOR MILITARY MEDICINE WHERE RADIOLOGICAL, CHEMICAL AND BIOLOGICAL AGENTS MAY PLAY AN IMPORTANT ROLE IN PATHOGENESIS. 2005 13 2185 33 EPIGENETIC MECHANISMS UNDERLYING HIV-INFECTION INDUCED SUSCEPTIBILITY OF CD4+ T CELLS TO ENHANCED ACTIVATION-INDUCED FASL EXPRESSION AND CELL DEATH. BACKGROUND: CHRONIC IMMUNE ACTIVATION AND CD4 T CELL DEPLETION ARE SIGNIFICANT PATHOGENIC FEATURES OF HIV INFECTION. EXPRESSION OF FAS LIGAND (FASL), A KEY MEDIATOR OF ACTIVATION-INDUCED CELL DEATH IN T CELLS, IS ELEVATED IN PEOPLE LIVING WITH HIV-1 INFECTION (PLWH). HOWEVER, THE EPIGENETIC MECHANISMS UNDERLYING THE ENHANCED INDUCTION OF FASL EXPRESSION IN CD4 T LYMPHOCYTES IN PLWH ARE NOT COMPLETELY ELUCIDATED. HENCE, THE CURRENT WORK EXAMINED THE EFFECT OF HIV INFECTION ON FASL PROMOTER-ASSOCIATED HISTONE MODIFICATIONS AND TRANSCRIPTIONAL REGULATION IN CD4 T LYMPHOCYTES IN PLWH. METHOD: FLOW CYTOMETRIC ANALYSIS WAS PERFORMED TO EXAMINE THE FAS-FASL EXPRESSION ON TOTAL CD4 T CELLS AND NAIVE/MEMORY CD4 T CELL SUBSETS. EPIGENETIC FASL PROMOTER HISTONE MODIFICATIONS WERE INVESTIGATED BY CHROMATIN IMMUNOPRECIPITATION-QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION ANALYSIS USING FRESHLY ISOLATED TOTAL CD4 T LYMPHOCYTES FROM HIV-1 INFECTED AND NONINFECTED INDIVIDUALS. RESULTS: ALL NAIVE/MEMORY CD4 T CELL SUBSETS FROM PLWH SHOWED MARKEDLY GREATER FREQUENCY OF FASL EXPRESSION. NOTABLY, EXAMINATION OF FUNCTIONAL OUTCOME OF FASL/FAS CO-EXPRESSION DEMONSTRATED THE PREFERENTIAL SUSCEPTIBILITY OF TCM AND TEM SUBSETS TO ACTIVATION-INDUCED APOPTOSIS. IMPORTANTLY, THESE CD4 T CELLS COLLECTIVELY DEMONSTRATED A DISTINCT FASL PROMOTER HISTONE PROFILE INVOLVING A COORDINATED CROSS-TALK BETWEEN HISTONE H3 MODIFICATIONS LEADING TO ENHANCED FASL GENE EXPRESSION. SPECIFICALLY, LEVELS OF TRANSCRIPTIONALLY PERMISSIVE HISTONE H3K4-TRIMETHYLATION (H3K4ME3) AND HISTONE H3K9-ACETYLATION (H3K9AC) WERE INCREASED, WITH A CONCOMITANT DECREASE IN THE REPRESSIVE H3K9-TRIMETHYLATION (H3K9ME3). CONCLUSION: THE PRESENT WORK DEMONSTRATES THAT EPIGENETIC MECHANISMS INVOLVING PROMOTER-HISTONE MODIFICATIONS REGULATE TRANSCRIPTIONAL COMPETENCE AND FASL EXPRESSION IN CD4 T CELLS FROM PLWH AND RENDER THEM SUSCEPTIBLE TO ACTIVATION-INDUCED CELL DEATH. 2021 14 6495 31 TRAINED IMMUNITY AS A POTENTIAL TARGET FOR THERAPEUTIC IMMUNOMODULATION IN DUCHENNE MUSCULAR DYSTROPHY. DYSREGULATED INFLAMMATION INVOLVING INNATE IMMUNE CELLS, PARTICULARLY OF THE MONOCYTE/MACROPHAGE LINEAGE, IS A KEY CONTRIBUTOR TO THE PATHOGENESIS OF DUCHENNE MUSCULAR DYSTROPHY (DMD). TRAINED IMMUNITY IS AN EVOLUTIONARILY ANCIENT PROTECTIVE MECHANISM AGAINST INFECTION, IN WHICH EPIGENETIC AND METABOLIC ALTERATIONS CONFER NON-SPECIFIC HYPERRESPONSIVENESS OF INNATE IMMUNE CELLS TO VARIOUS STIMULI. RECENT WORK IN AN ANIMAL MODEL OF DMD (MDX MICE) HAS SHOWN THAT MACROPHAGES EXHIBIT CARDINAL FEATURES OF TRAINED IMMUNITY, INCLUDING THE PRESENCE OF INNATE IMMUNE SYSTEM "MEMORY". THE LATTER IS REFLECTED BY EPIGENETIC CHANGES AND DURABLE TRANSMISSIBILITY OF THE TRAINED PHENOTYPE TO HEALTHY NON-DYSTROPHIC MICE BY BONE MARROW TRANSPLANTATION. MECHANISTICALLY, IT IS SUGGESTED THAT A TOLL-LIKE RECEPTOR (TLR) 4-REGULATED, MEMORY-LIKE CAPACITY OF INNATE IMMUNITY IS INDUCED AT THE LEVEL OF THE BONE MARROW BY FACTORS RELEASED FROM THE DAMAGED MUSCLES, LEADING TO EXAGGERATED UPREGULATION OF BOTH PRO- AND ANTI-INFLAMMATORY GENES. HERE WE PROPOSE A CONCEPTUAL FRAMEWORK FOR THE INVOLVEMENT OF TRAINED IMMUNITY IN DMD PATHOGENESIS AND ITS POTENTIAL TO SERVE AS A NEW THERAPEUTIC TARGET. 2023 15 5760 30 SOLUBLE URIC ACID PRIMES TLR-INDUCED PROINFLAMMATORY CYTOKINE PRODUCTION BY HUMAN PRIMARY CELLS VIA INHIBITION OF IL-1RA. OBJECTIVES: THE STUDY OF THE PROINFLAMMATORY ROLE OF URIC ACID HAS FOCUSED ON THE EFFECTS OF ITS CRYSTALS OF MONOSODIUM URATE (MSU). HOWEVER, LITTLE IS KNOWN WHETHER URIC ACID ITSELF CAN DIRECTLY HAVE PROINFLAMMATORY EFFECTS. IN THIS STUDY, WE INVESTIGATE THE PRIMING EFFECTS OF URIC ACID EXPOSURE ON THE CYTOKINE PRODUCTION OF PRIMARY HUMAN CELLS UPON STIMULATION WITH GOUT-RELATED STIMULI. METHODS: PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) WERE HARVESTED FROM PATIENTS WITH GOUT AND HEALTHY VOLUNTEERS. CELLS WERE PRETREATED WITH OR WITHOUT URIC ACID IN SOLUBLE FORM FOR 24 H AND THEN STIMULATED FOR 24 H WITH TOLL-LIKE RECEPTOR (TLR)2 OR TLR4 LIGANDS IN THE PRESENCE OR ABSENCE OF MSU CRYSTALS. CYTOKINE PRODUCTION WAS MEASURED BY ELISA; MRNA LEVELS WERE ASSESSED USING QPCR. RESULTS: THE PRODUCTION OF INTERLEUKIN (IL)-1BETA AND IL-6 WAS HIGHER IN PATIENTS COMPARED WITH CONTROLS AND THIS CORRELATED WITH SERUM URATE LEVELS. PROINFLAMMATORY CYTOKINE PRODUCTION WAS SIGNIFICANTLY POTENTIATED WHEN CELLS FROM HEALTHY SUBJECTS WERE PRETREATED WITH URIC ACID. SURPRISINGLY, THIS WAS ASSOCIATED WITH A SIGNIFICANT DOWNREGULATION OF THE ANTI-INFLAMMATORY CYTOKINE IL-1 RECEPTOR ANTAGONIST (IL-1RA). THIS EFFECT WAS SPECIFIC TO STIMULATION BY URIC ACID AND WAS EXERTED AT THE LEVEL OF GENE TRANSCRIPTION. EPIGENETIC REPROGRAMMING AT THE LEVEL OF HISTONE METHYLATION BY URIC ACID WAS INVOLVED IN THIS EFFECT. CONCLUSIONS: IN THIS STUDY WE DEMONSTRATE A MECHANISM THROUGH WHICH HIGH CONCENTRATIONS OF URIC ACID (UP TO 50 MG/DL) INFLUENCE INFLAMMATORY RESPONSES BY FACILITATING IL-1BETA PRODUCTION IN PBMCS. WE SHOW THAT A MECHANISM FOR THE AMPLIFICATION OF IL-1BETA CONSISTS IN THE DOWNREGULATION OF IL-1RA AND THAT THIS EFFECT COULD BE EXERTED VIA EPIGENETIC MECHANISMS SUCH AS HISTONE METHYLATION. HYPERURICAEMIA CAUSES A SHIFT IN THE IL-1BETA/IL-1RA BALANCE PRODUCED BY PBMCS AFTER EXPOSURE TO MSU CRYSTALS AND TLR-MEDIATED STIMULI, AND THIS PHENOMENON IS LIKELY TO REINFORCE THE ENHANCED STATE OF CHRONIC INFLAMMATION. 2016 16 6540 32 TRANSCRIPTIONAL, EPIGENETIC, AND FUNCTIONAL REPROGRAMMING OF MONOCYTES FROM NON-HUMAN PRIMATES FOLLOWING CHRONIC ALCOHOL DRINKING. CHRONIC HEAVY DRINKING (CHD) OF ALCOHOL IS A KNOWN RISK FACTOR FOR INCREASED SUSCEPTIBILITY TO BACTERIAL AND VIRAL INFECTION AS WELL AS IMPAIRED WOUND HEALING. EVIDENCE SUGGESTS THAT THESE DEFECTS ARE MEDIATED BY A DYSREGULATED INFLAMMATORY RESPONSE ORIGINATING FROM MYELOID CELLS, NOTABLY MONOCYTES AND MACROPHAGES, BUT THE MECHANISMS REMAIN POORLY UNDERSTOOD. OUR ABILITY TO STUDY CHD IS IMPACTED BY THE COMPLEXITIES OF HUMAN DRINKING PATTERNS AND BEHAVIOR AS WELL AS COMORBIDITIES AND CONFOUNDING RISK FACTORS FOR PATIENTS WITH ALCOHOL USE DISORDERS. TO OVERCOME THESE CHALLENGES, WE UTILIZED A TRANSLATIONAL RHESUS MACAQUE MODEL OF VOLUNTARY ETHANOL SELF-ADMINISTRATION THAT CLOSELY RECAPITULATES HUMAN DRINKING PATTERNS AND CHRONICITY. IN THIS STUDY, WE EXAMINED THE EFFECTS OF CHD ON BLOOD MONOCYTES IN CONTROL AND CHD FEMALE MACAQUES AFTER 12 MONTHS OF DAILY ETHANOL CONSUMPTION. WHILE MONOCYTES FROM CHD FEMALE MACAQUES GENERATED A HYPER-INFLAMMATORY RESPONSE TO EX VIVO LPS STIMULATION, THEIR RESPONSE TO E. COLI WAS DAMPENED. IN DEPTH SCRNA-SEQ ANALYSIS OF PURIFIED MONOCYTES REVEALED SIGNIFICANT SHIFTS IN CLASSICAL MONOCYTE SUBSETS WITH ACCUMULATION OF CELLS EXPRESSING MARKERS OF HYPOXIA (HIF1A) AND INFLAMMATION (NFKB SIGNALING PATHWAY) IN CHD MACAQUES. THE INCREASED PRESENCE OF MONOCYTE SUBSETS SKEWED TOWARDS INFLAMMATORY PHENOTYPES WAS COMPLEMENTED BY EPIGENETIC ANALYSIS, WHICH REVEALED HIGHER ACCESSIBILITY OF PROMOTER REGIONS THAT REGULATE GENES INVOLVED IN CYTOKINE SIGNALING PATHWAYS. COLLECTIVELY, DATA PRESENTED IN THIS MANUSCRIPT DEMONSTRATE THAT CHD SHIFTS CLASSICAL MONOCYTE SUBSET COMPOSITION AND PRIMES THE MONOCYTES TOWARDS A MORE HYPER-INFLAMMATORY RESPONSE TO LPS, BUT COMPROMISED PATHOGEN RESPONSE. 2021 17 3737 42 INNATE IMMUNITY, EPIGENETICS AND AUTOIMMUNITY IN RHEUMATOID ARTHRITIS. RHEUMATOID ARTHRITIS (RA) IS A CHRONIC INFLAMMATORY AUTOIMMUNE DISEASE CHARACTERIZED BY THE PROGRESSIVE AND IRREVERSIBLE DESTRUCTION OF JOINTS. RA REMAINS AN INCURABLE CONDITION, ALTHOUGH A NEW CLASS OF DRUGS, BIOLOGICALS, HAVE MADE A MAJOR BREAKTHROUGH IN TARGETING AND/OR ELIMINATING THE IMMUNE CELLS, INCLUDING T CELLS, B CELLS AND MONOCYTES/MACROPHAGES FROM THE JOINTS. THAT WE CANNOT (YET?) CURE THE DISEASE IS MOST LIKELY DUE TO THE LACK OF THERAPEUTIC TARGETING THE ENDOGENOUSLY ACTIVATED RA SYNOVIAL FIBROBLASTS (RASF). MOST INTERESTINGLY, RASF EXPRESS TOLL-LIKE RECEPTORS (TLRS) 1-6 RENDERING THEM PRONE TO ACTIVATION BY EXOGENOUS AND ENDOGENOUS TLR LIGANDS AND RESULTING IN THE PRODUCTION OF NUMEROUS POWERFUL CHEMOKINES AND CYTOKINES. THESE FACTORS ARE RESPONSIBLE FOR THE REPOPULATION OF IMMUNE CELLS IN THE JOINTS AFTER CEASING CELL DEPLETING THERAPIES. TO CHARACTERIZE THE MOLECULAR MECHANISMS OF SYNOVIAL ACTIVATION, A NEW APPROACH STUDYING THE EPIGENETIC CHARACTERISTICS OF RASF HAS BEEN RECENTLY UNDERTAKEN. THEREBY, THE PATTERN OF HISTONE ACETYLATION, DNA METHYLATION AND GENE EXPRESSION REGULATING MICRORNA ARE BEING EXPLORED. SINCE AUTO-ANTIBODIES HAVE THE MOST PREDICTIVE AND DIAGNOSTIC VALUE FOR RA, IT IS CHALLENGING TO STUDY MORE COMPREHENSIVELY THE CONTRIBUTION OF AUTO-ANTIBODIES TO THE DISEASE. A NEW SCREENING TECHNIQUE, SEROLOGICAL ANALYSIS OF RECOMBINANT HUMAN CDNA EXPRESSION LIBRARY (SEREX), ADAPTED FROM CANCER RESEARCH ALLOWED FOR THE IDENTIFICATION OF NOVEL AUTO-ANTIBODIES IN RA, INCLUDING ANTI-SERPIN E2 AUTO-ANTIBODIES. THE SERPIN E2 AUTO-ANTIBODIES WERE FOUND TO INHIBIT THE ACTIVITY OF SERPIN E2 AND HAVE POTENTIALLY A FUNCTIONAL ROLE IN THE DISEASE. THE RECENT FINDINGS IN THE FIELD OF INNATE IMMUNITY, EPIGENETICS AND AUTOIMMUNITY RELATED TO THE PATHOGENESIS OF RA ARE IN THE SCOPE OF THIS REVIEW. 2009 18 1061 33 CLINICAL REMISSION OF SIGHT-THREATENING NON-INFECTIOUS UVEITIS IS CHARACTERIZED BY AN UPREGULATION OF PERIPHERAL T-REGULATORY CELL POLARIZED TOWARDS T-BET AND TIGIT. BACKGROUND: NON-INFECTIOUS UVEITIS CAN CAUSE CHRONIC RELAPSING AND REMITTING OCULAR INFLAMMATION, WHICH MAY REQUIRE HIGH DOSE SYSTEMIC IMMUNOSUPPRESSION TO PREVENT SEVERE SIGHT LOSS. IT HAS BEEN CLASSICALLY DESCRIBED AS AN AUTOIMMUNE DISEASE, MEDIATED BY PRO-INFLAMMATORY TH1 AND TH17 T-CELL SUBSETS. STUDIES SUGGEST THAT NATURAL IMMUNOSUPPRESSIVE CD4(+)CD25(+)FOXP3(+) T-REGULATORY CELLS (TREGS) ARE INVOLVED IN RESOLUTION OF INFLAMMATION AND MAY BE INVOLVED IN THE MAINTENANCE OF CLINICAL REMISSION. OBJECTIVE: TO INVESTIGATE WHETHER THERE IS A PERIPHERAL BLOOD IMMUNOREGULATORY PHENOTYPE ASSOCIATED WITH CLINICAL REMISSION OF SIGHT-THREATENING NON-INFECTIOUS UVEITIS BY COMPARING PERIPHERAL BLOOD LEVELS OF TREG, TH1, AND TH17, AND ASSOCIATED DNA METHYLATION AND CYTOKINE LEVELS IN PATIENTS WITH ACTIVE UVEITIC DISEASE, CONTROL SUBJECTS AND PATIENTS (WITH PREVIOUSLY ACTIVE DISEASE) IN CLINICAL REMISSION INDUCED BY IMMUNOSUPPRESSIVE DRUGS. METHODS: ISOLATED PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMC) FROM PERIPHERAL BLOOD SAMPLES FROM PROSPECTIVELY RECRUITED SUBJECTS WERE ANALYZED BY FLOW CYTOMETRY FOR CD3, CD4, FOXP3, TIGIT, T-BET, AND RELATED ORPHAN RECEPTOR GAMMAT. EPIGENETIC DNA METHYLATION LEVELS OF FOXP3 TREG-SPECIFIC DEMETHYLATED REGION (TSDR), FOXP3 PROMOTER, TBX21, RORC2, AND TIGIT LOCI WERE DETERMINED IN CRYOPRESERVED PBMC USING A NEXT-GENERATION SEQUENCING APPROACH. RELATED CYTOKINES WERE MEASURED IN BLOOD SERA. FUNCTIONAL SUPPRESSIVE CAPACITY OF TREG WAS ASSESSED USING T-CELL PROLIFERATION ASSAYS. RESULTS: FIFTY PATIENTS WITH UVEITIS (INTERMEDIATE, POSTERIOR, AND PANUVEITIS) AND 10 CONTROL SUBJECTS WERE RECRUITED. THE FREQUENCY OF CD4(+)CD25(+)FOXP3(+) TREG, TIGIT(+) TREG, AND T-BET(+) TREG AND THE RATIO OF TREG TO TH1 WERE SIGNIFICANTLY HIGHER IN REMISSION PATIENTS COMPARED WITH PATIENTS WITH ACTIVE UVEITIC DISEASE; AND TIGIT(+) TREGS WERE A SIGNIFICANT PREDICTOR OF CLINICAL REMISSION. TREG FROM PATIENTS IN CLINICAL REMISSION DEMONSTRATED A HIGH LEVEL OF IN VITRO SUPPRESSIVE FUNCTION COMPARED WITH TREG FROM CONTROL SUBJECTS AND FROM PATIENTS WITH UNTREATED ACTIVE DISEASE. PBMC FROM PATIENTS IN CLINICAL REMISSION HAD SIGNIFICANTLY LOWER METHYLATION LEVELS AT THE FOXP3 TSDR, FOXP3 PROMOTER, AND TIGIT LOCI AND HIGHER LEVELS AT RORC LOCI THAN THOSE WITH ACTIVE DISEASE. CLINICAL REMISSION WAS ALSO ASSOCIATED WITH SIGNIFICANTLY HIGHER SERUM LEVELS OF TRANSFORMING GROWTH FACTOR BETA AND IL-10, WHICH POSITIVELY CORRELATED WITH TREG LEVELS, AND LOWER SERUM LEVELS OF IFNGAMMA, IL-17A, AND IL-22 COMPARED WITH PATIENTS WITH ACTIVE DISEASE. CONCLUSION: CLINICAL REMISSION OF SIGHT-THREATENING NON-INFECTIOUS UVEITIS HAS AN IMMUNOREGULATORY PHENOTYPE CHARACTERIZED BY UPREGULATION OF PERIPHERAL TREG, POLARIZED TOWARD T-BET AND TIGIT. THESE FINDINGS MAY ASSIST WITH INDIVIDUALIZED THERAPY OF UVEITIS, BY INFORMING WHETHER DRUG THERAPY HAS INDUCED PHENOTYPICALLY STABLE TREG ASSOCIATED WITH LONG-TERM CLINICAL REMISSION. 2018 19 6599 25 TWIST1 AND TWIST2 INDUCE HUMAN MACROPHAGE MEMORY UPON CHRONIC INNATE RECEPTOR TREATMENT BY HDAC-MEDIATED DEACETYLATION OF CYTOKINE PROMOTERS. INTESTINAL TISSUES ARE CONTINUOUSLY EXPOSED TO MICROBIAL PRODUCTS THAT STIMULATE PATTERN-RECOGNITION RECEPTORS (PRRS). ONGOING PRR STIMULATION CAN CONFER EPIGENETIC CHANGES IN MACROPHAGES, WHICH CAN THEN REGULATE SUBSEQUENT IMMUNE OUTCOMES AND ADAPTATION TO THE LOCAL ENVIRONMENT. MECHANISMS LEADING TO THESE CHANGES ARE INCOMPLETELY UNDERSTOOD. WE FOUND THAT SHORT-TERM STIMULATION OF THE PRR NOD2 IN PRIMARY HUMAN MONOCYTE-DERIVED MACROPHAGES RESULTED IN INCREASED H3 AND H4 ACETYLATION OF CYTOKINE PROMOTERS, CONSISTENT WITH THE INCREASED CYTOKINE SECRETION OBSERVED. HOWEVER, WITH PROLONGED NOD2 STIMULATION, BOTH THE ACETYLATION AND CYTOKINE SECRETION WERE DRAMATICALLY DECREASED. CHRONIC NOD2 STIMULATION UPREGULATED THE TRANSCRIPTION FACTORS TWIST1 AND TWIST2, WHICH BOUND TO THE PROMOTERS OF THE HISTONE DEACETYLASES HDAC1 AND HDAC3 AND INDUCED HDAC1 AND HDAC3 EXPRESSION. HDAC1 AND HDAC3 THEN MEDIATED HISTONE DEACETYLATION AT CYTOKINE PROMOTERS AND, IN TURN, CYTOKINE DOWNREGULATION UNDER THESE CONDITIONS. SIMILAR REGULATION WAS OBSERVED UPON CHRONIC STIMULATION OF MULTIPLE PRRS. CONSISTENT WITH THE CHRONIC MICROBIAL EXPOSURE IN THE INTESTINAL ENVIRONMENT, TWIST1, TWIST2, HDAC1, AND HDAC3 WERE UPREGULATED IN HUMAN INTESTINAL RELATIVE TO PERIPHERAL MACROPHAGES. IMPORTANTLY, COMPLEMENTING HDAC1 AND HDAC3 IN TWIST1/TWIST2-DEFICIENT MONOCYTE-DERIVED MACROPHAGES RESTORED THE REDUCED HISTONE ACETYLATION ON CYTOKINE PROMOTERS AND THE DECREASED CYTOKINE SECRETION WITH CHRONIC NOD2 STIMULATION. TAKEN TOGETHER, WE IDENTIFY MECHANISMS WHEREIN TWIST1 AND TWIST2 PROMOTE CHROMATIN MODIFICATIONS, RESULTING IN MACROPHAGE INSTRUCTION AND ADAPTATION TO CONDITIONS IN THE INTESTINAL MICROENVIRONMENT. 2019 20 6110 27 THE EPIGENETIC ALTERATION OF SYNOVIAL CELL GENE EXPRESSION IN RHEUMATOID ARTHRITIS AND THE ROLES OF NUCLEAR FACTOR KAPPAB AND NOTCH SIGNALING PATHWAYS. RHEUMATOID ARTHRITIS (RA) IS A COMPLEX PROCESS OF CHRONIC AND PROGRESSIVE INFLAMMATION ASSOCIATED WITH ACTIVATION OF NUMEROUS SIGNALING MOLECULES AND TRANSCRIPTION FACTORS AND HYPERPROLIFERATION OF SYNOVIOCYTES OF THE AFFECTED JOINTS, ALTHOUGH THE GREATER PART OF ITS PATHOPHYSIOLOGICAL PROCESS IS EXPLAINED BY ACTIVATION OF NUCLEAR FACTOR KAPPAB (NF-KAPPAB). FOR EXAMPLE, THE SELF-PERPETUATING NATURE OF THE RHEUMATOID INFLAMMATION IS ASCRIBABLE TO OVEREXPRESSION OF THE PROINFLAMMATORY CYTOKINES TUMOR NECROSIS FACTOR ALPHA AND INTERLEUKIN-1BETA, KNOWN TO ELICIT THE ACTIVATION CASCADE FOR NF-KAPPAB AND ACTIVATOR PROTEIN-1 THAT ARE RESPONSIBLE FOR TRANSCRIPTIONAL INDUCTION OF THESE CYTOKINES AMONG OTHER TARGET GENES, WHICH CONFORM A POSITIVE FEEDBACK LOOP FOR CONTINUATION AND EXPANSION OF THE INFLAMMATORY RESPONSES. IN ADDITION, COMPARATIVE GENE EXPRESSION PROFILE ANALYSES HAVE REVEALED ACTIVATION OF A NUMBER OF GENES THAT EXPLAIN THE "TRANSFORMED-LIKE" PHENOTYPE OF SYNOVIOCYTES. AMONG THE GENES EXPRESSED IN RHEUMATOID SYNOVIOCYTES UPON INFLAMMATORY STIMULI, INDUCTION OF GENE EXPRESSION OF NOTCH PROTEINS AND ITS LIGAND HAVE BEEN FOUND. POSSIBLE ROLES OF NOTCH SIGNALING IN RA SYNOVIOCYTES ARE DISCUSSED. 2005