1 1703 155 DYNAMICS AND EPIGENETIC SIGNATURE OF REGULATORY T-CELLS FOLLOWING ANTIRETROVIRAL THERAPY INITIATION IN ACUTE HIV INFECTION. BACKGROUND: HIV INFECTION PROMOTES THE EXPANSION OF IMMUNOSUPPRESSIVE REGULATORY T-CELLS (TREGS), CONTRIBUTING TO IMMUNE DYSFUNCTION, TISSUE FIBROSIS AND DISEASE PROGRESSION. EARLY ANTIRETROVIRAL TREATMENT (ART) UPON HIV INFECTION IMPROVES CD4 COUNT AND DECREASES IMMUNE ACTIVATION. HOWEVER, TREG DYNAMICS AND THEIR EPIGENETIC REGULATION FOLLOWING EARLY ART INITIATION REMAIN UNDERSTUDIED. METHODS: TREG SUBSETS WERE CHARACTERIZED BY FLOW CYTOMETRY IN 103 INDIVIDUALS, INCLUDING UNTREATED HIV-INFECTED PARTICIPANTS IN ACUTE AND CHRONIC PHASES, ART-TREATED IN EARLY INFECTION, ELITE CONTROLLERS (ECS), IMMUNOLOGICAL CONTROLLERS (ICS), AND HIV-UNINFECTED CONTROLS. THE METHYLATION STATUS OF SIX REGULATORY REGIONS OF THE FOXP3 GENE WAS ASSESSED USING MISEQ TECHNOLOGY. FINDINGS: TOTAL TREG FREQUENCY INCREASED OVERTIME DURING HIV INFECTION, WHICH WAS NORMALIZED IN EARLY ART RECIPIENTS. TREGS IN UNTREATED INDIVIDUALS EXPRESSED HIGHER LEVELS OF ACTIVATION AND IMMUNOSUPPRESSIVE MARKERS (CD39, AND LAP(TGF-BETA1)), WHICH REMAINED UNCHANGED FOLLOWING EARLY ART. EXPRESSION OF GUT MIGRATION MARKERS (CCR9, INTEGRIN-BETA7) BY TREGS WAS ELEVATED DURING UNTREATED HIV INFECTION, WHILE THEY DECLINED WITH THE DURATION OF ART BUT NOT UPON EARLY ART INITIATION. NOTABLY, GUT-HOMING TREGS EXPRESSING LAP(TGF-BETA1) AND CD39 REMAINED HIGHER DESPITE EARLY TREATMENT. ADDITIONALLY, THE INCREASE IN LAP(TGF-BETA1)(+) TREGS OVERTIME WERE CONSISTENT WITH HIGHER DEMETHYLATION OF CONSERVED NON-CODING SEQUENCE (CNS)-1 IN THE FOXP3 GENE. REMARKABLY, LAP(TGF-BETA1)-EXPRESSING TREGS IN ECS WERE SIGNIFICANTLY HIGHER THAN IN UNINFECTED SUBJECTS, WHILE THE MARKERS OF TREG ACTIVATION AND GUT MIGRATION WERE NOT DIFFERENT. INTERPRETATION: EARLY ART INITIATION WAS UNABLE TO CONTROL THE LEVELS OF IMMUNOSUPPRESSIVE TREG SUBSETS AND THEIR GUT MIGRATION POTENTIAL, WHICH COULD ULTIMATELY CONTRIBUTE TO GUT TISSUE FIBROSIS AND HIV DISEASE PROGRESSION. FUNDING: THIS STUDY WAS FUNDED BY THE CANADIAN INSTITUTES OF HEALTH RESEARCH (CIHR, GRANT MOP 142294) AND IN PART BY THE AIDS AND INFECTIOUS DISEASES NETWORK OF THE RESEAU SIDA ET MALADIES INFECTIEUSES DU FONDS DE RECHERCHE DU QUEBEC-SANTE (FRQ-S). 2021 2 3662 35 INDUCTION OF STABLE HUMAN FOXP3(+) TREGS BY A PARASITE-DERIVED TGF-BETA MIMIC. IMMUNE HOMEOSTASIS IN THE INTESTINE IS TIGHTLY CONTROLLED BY FOXP3(+) REGULATORY T CELLS (TREGS), DEFECTS OF WHICH ARE LINKED TO THE DEVELOPMENT OF CHRONIC CONDITIONS, SUCH AS INFLAMMATORY BOWEL DISEASE (IBD). AS A MECHANISM OF IMMUNE EVASION, SEVERAL SPECIES OF INTESTINAL PARASITES BOOST TREG ACTIVITY. THE PARASITE HELIGMOSOMOIDES POLYGYRUS IS KNOWN TO SECRETE A MOLECULE (HP-TGM) THAT MIMICS THE ABILITY OF TGF-BETA TO INDUCE FOXP3 EXPRESSION IN CD4(+) T CELLS. THE STUDY AIMED TO INVESTIGATE WHETHER HP-TGM COULD INDUCE HUMAN FOXP3(+) TREGS AS A POTENTIAL THERAPEUTIC APPROACH FOR INFLAMMATORY DISEASES. CD4(+) T CELLS FROM HEALTHY VOLUNTEERS WERE EXPANDED IN THE PRESENCE OF HP-TGM OR TGF-BETA. TREG INDUCTION WAS MEASURED BY FLOW CYTOMETRIC DETECTION OF FOXP3 AND OTHER TREG MARKERS, SUCH AS CD25 AND CTLA-4. EPIGENETIC CHANGES WERE DETECTED USING CHIP-SEQ AND PYROSEQUENCING OF FOXP3. TREG PHENOTYPE STABILITY WAS ASSESSED FOLLOWING INFLAMMATORY CYTOKINE CHALLENGE AND TREG FUNCTION WAS EVALUATED BY CELLULAR CO-CULTURE SUPPRESSION ASSAYS AND CYTOMETRIC BEAD ARRAYS FOR SECRETED CYTOKINES. HP-TGM EFFICIENTLY INDUCED FOXP3 EXPRESSION (> 60%), IN ADDITION TO CD25 AND CTLA-4, AND CAUSED EPIGENETIC MODIFICATION OF THE FOXP3 LOCUS TO A GREATER EXTENT THAN TGF-BETA. HP-TGM-INDUCED TREGS HAD SUPERIOR SUPPRESSIVE FUNCTION COMPARED WITH TGF-BETA-INDUCED TREGS, AND RETAINED THEIR PHENOTYPE FOLLOWING EXPOSURE TO INFLAMMATORY CYTOKINES. FURTHERMORE, HP-TGM INDUCED A TREG-LIKE PHENOTYPE IN IN VIVO DIFFERENTIATED TH1 AND TH17 CELLS, INDICATING ITS POTENTIAL TO RE-PROGRAM MEMORY CELLS TO ENHANCE IMMUNE TOLERANCE. THESE DATA INDICATE HP-TGM HAS POTENTIAL TO BE USED TO GENERATE STABLE HUMAN FOXP3(+) TREGS TO TREAT IBD AND OTHER INFLAMMATORY DISEASES. 2021 3 6186 24 THE IMPACT OF HIV INFECTION ON THE FREQUENCIES, FUNCTION, SPATIAL LOCALIZATION AND HETEROGENEITY OF T FOLLICULAR REGULATORY CELLS (TFRS) WITHIN HUMAN LYMPH NODES. BACKGROUND: HIV ERADICATION EFFORTS HAVE BEEN UNSUCCESSFUL PARTLY DUE TO VIRUS PERSISTENCE IN IMMUNE SANCTUARY SITES SUCH AS GERMINAL CENTRES WITHIN LYMPH NODE (LN) TISSUES. RECENT EVIDENCE SUGGESTS THAT LNS HARBOUR A NOVEL SUBSET OF REGULATORY T CELLS, TERMED FOLLICULAR REGULATORY T CELLS (TFRS), BUT THEIR ROLE IN HIV PATHOGENESIS IS NOT FULLY ELUCIDATED. RESULTS: PAIRED EXCISIONAL LN AND PERIPHERAL BLOOD SAMPLES OBTAINED FROM 20 HIV-UNINFECTED AND 31 HIV-INFECTED TREATED AND 7 CHRONIC UNTREATED, WERE USED TO DETERMINE IF AND HOW HIV INFECTION MODULATE FREQUENCIES, FUNCTION AND SPATIAL LOCALIZATION OF TFRS WITHIN LN TISSUES. IMAGING STUDIES SHOWED THAT MOST TFRS ARE LOCALIZED IN EXTRA-FOLLICULAR REGIONS. CO-CULTURE ASSAYS SHOWED TFRS SUPPRESSION OF TFH HELP TO B CELLS. IMPORTANTLY, EPIGENETIC AND TRANSCRIPTIONAL STUDIES IDENTIFIED DPP4 AND FCRL3 AS NOVEL PHENOTYPIC MARKERS THAT DEFINE FOUR FUNCTIONALLY DISTINCT TFR SUBPOPULATIONS IN HUMAN LNS REGARDLESS OF HIV STATUS. IMAGING STUDIES CONFIRMED THE REGULATORY PHENOTYPE OF DPP4(+)TFRS. CONCLUSION: TOGETHER THESE STUDIES DESCRIBE TFRS DYNAMIC CHANGES DURING HIV INFECTION AND REVEAL PREVIOUSLY UNDERAPPRECIATED TFR HETEROGENEITY WITHIN HUMAN LNS. 2022 4 272 30 AGE-DEPENDENT DECREASE IN THE INDUCTION OF REGULATORY T CELLS IS ASSOCIATED WITH DECREASED EXPRESSION OF RALDH2 IN MESENTERIC LYMPH NODE DENDRITIC CELLS. A DECLINE IN IMMUNE FUNCTION WITH AGING HAS BEEN REPORTED. REGULATORY T CELL (TREG) INDUCTION IS KNOWN TO DECREASE WITH AGE, AND ELUCIDATING THE UNDERLYING MECHANISM IS IMPORTANT FOR PREVENTING AGE-RELATED DISEASES DUE TO AGE-RELATED CHRONIC INFLAMMATION. IN THE INTESTINE, DENDRITIC CELLS (DCS) PLAY AN IMPORTANT ROLE IN INDUCING TREGS SPECIFIC TO ORAL ANTIGENS, AND THEY EFFICIENTLY INDUCE TREGS VIA PRODUCTION OF RETINOIC ACID (RA), A VITAMIN A METABOLITE, CATALYZED BY THE ENZYME RETINALDEHYDE DEHYDROGENASE 2 (RALDH2). WE HAVE PREVIOUSLY REPORTED THAT IN THE MESENTERIC LYMPH NODE (MLN), A SECONDARY LYMPHOID TISSUE IN WHICH IMMUNE RESPONSES TO ORAL ANTIGENS ARE INDUCED, FOUR DC SUBSETS EXPRESS DIFFERENT LEVELS OF CD11B, CD103, AND PD-L1, AND WE HAVE REPORTED THAT THE CD11B(-)CD103(+)PD-L1(HIGH) SUBSET EXPRESSES THE HIGHEST LEVELS OF THE RALDH2 GENE AND INDUCES TREGS IN VITRO. WE EXAMINED TREG INDUCTION IN YOUNG AND AGED MICE USING A TREG INDUCTION MODEL BY ADMINISTERING A FOOD ANTIGEN, AND WE FOUND THAT ANTIGEN-SPECIFIC TREG INDUCTION WAS DECREASED IN AGED MICE. WE FURTHER INVESTIGATED THE MLN DCS, AND A SIGNIFICANT DECREASE IN RALDH2 GENE EXPRESSION WAS OBSERVED IN MLN DCS FROM AGED MICE. AS FACTORS, WE FOUND THAT THE PROPORTION OF THE CD11B(-)CD103(+)PD-L1(HIGH) SUBSET WAS DECREASED IN AGED MICE COMPARED WITH THAT IN YOUNG MICE AND THAT RALDH ENZYME ACTIVITY WAS DECREASED IN THE CD11B(-)CD103(+)PD-L1(HIGH) AND CD11B(+)CD103(+)PD-L1(HIGH) SUBSETS. FURTHERMORE, ANALYSIS OF THE METHYLATION OF THE RALDH2 GENE PROMOTER REGION REVEALED THAT CPG MOTIFS WERE MORE METHYLATED IN THE MLN DCS OF AGED MICE, SUGGESTING THAT RALDH2 EXPRESSION WAS SUPPRESSED BY EPIGENETIC CHANGES. FINALLY, WE FOUND THAT RA TREATMENT TENDED TO INCREASE TREG INDUCTION. THESE RESULTS SUGGEST THAT THE REGULATION OF RA PRODUCTION MAY BE INVOLVED IN THE AGE-RELATED DECREASE IN ANTIGEN-SPECIFIC TREG INDUCTION. 2020 5 2270 29 EPIGENETIC QUANTIFICATION OF IMMUNOSENESCENT CD8(+) TEMRA CELLS IN HUMAN BLOOD. AGE-RELATED CHANGES IN HUMAN T-CELL POPULATIONS ARE IMPORTANT CONTRIBUTORS TO IMMUNOSENESCENCE. IN PARTICULAR, TERMINALLY DIFFERENTIATED CD8(+) EFFECTOR MEMORY CD45RA(+) TEMRA CELLS AND THEIR SUBSETS HAVE CHARACTERISTICS OF CELLULAR SENESCENCE, ACCUMULATE IN OLDER INDIVIDUALS, AND ARE INCREASED IN AGE-RELATED CHRONIC INFLAMMATORY DISEASES. IN A DETAILED T-CELL PROFILING AMONG INDIVIDUALS OVER 65 YEARS OF AGE, WE FOUND A HIGH INTERINDIVIDUAL VARIATION AMONG CD8(+) TEMRA POPULATIONS. CD8(+) TEMRA PROPORTIONS CORRELATED POSITIVELY WITH CYTOMEGALOVIRUS (CMV) ANTIBODY LEVELS, HOWEVER, NOT WITH THE CHRONOLOGICAL AGE. IN THE ANALYSIS OF OVER 90 INFLAMMATION PROTEINS, WE IDENTIFIED PLASMA TRANCE/RANKL LEVELS TO ASSOCIATE WITH SEVERAL DIFFERENTIATED T-CELL POPULATIONS, INCLUDING CD8(+) TEMRA AND ITS CD28(-) SUBSETS. GIVEN THE STRONG POTENTIAL OF CD8(+) TEMRA CELLS AS A BIOMARKER FOR IMMUNOSENESCENCE, WE USED DEEP-AMPLICON BISULFITE SEQUENCING TO MATCH THEIR FREQUENCIES IN FLOW CYTOMETRY WITH CPG SITE METHYLATION LEVELS AND DEVELOPED A COMPUTATIONAL MODEL TO PREDICT CD8(+) TEMRA CELL PROPORTIONS FROM WHOLE BLOOD GENOMIC DNA. OUR FINDINGS CONFIRM THE ASSOCIATION OF CD8(+) TEMRA AND ITS SUBSETS WITH CMV INFECTION AND PROVIDE A NOVEL TOOL FOR THEIR HIGH THROUGHPUT EPIGENETIC QUANTIFICATION AS A BIOMARKER OF IMMUNOSENESCENCE. 2022 6 3390 28 HOPX PLAYS A CRITICAL ROLE IN ANTIRETROVIRAL DRUGS INDUCED EPIGENETIC MODIFICATION AND CARDIAC HYPERTROPHY. PEOPLE LIVING WITH HIV (PLWH) HAVE TO TAKE AN ANTIRETROVIRAL THERAPY (ART) FOR LIFE AND SHOW NONCOMMUNICABLE ILLNESSES SUCH AS CHRONIC INFLAMMATION, IMMUNE ACTIVATION, AND MULTIORGAN DYSREGULATION. RECENT STUDIES SUGGEST THAT LONG-TERM USE OF ART INDUCES COMORBID CONDITIONS AND IS ONE OF THE LEADING CAUSES OF HEART FAILURE IN PLWH. HOWEVER, THE MOLECULAR MECHANISM OF ANTIRETROVIRAL DRUGS (ARVS) INDUCED HEART FAILURE IS UNCLEAR. TO DETERMINE THE MECHANISM OF ARVS INDUCED CARDIAC DYSFUNCTION, WE PERFORMED GLOBAL TRANSCRIPTOMIC PROFILING OF ARVS TREATED NEONATAL RAT VENTRICULAR CARDIOMYOCYTES IN CULTURE. DIFFERENTIALLY EXPRESSED GENES WERE IDENTIFIED BY RNA-SEQUENCING. OUR DATA SHOW THAT ARVS TREATMENT CAUSES UPREGULATION OF SEVERAL BIOLOGICAL FUNCTIONS ASSOCIATED WITH CARDIOTOXICITY, HYPERTROPHY, AND HEART FAILURE. GLOBAL GENE EXPRESSION DATA WERE VALIDATED IN CARDIAC TISSUE ISOLATED FROM HIV PATIENTS HAVING A HISTORY OF ART. INTERESTINGLY, WE FOUND THAT HOMEODOMAIN-ONLY PROTEIN HOMEOBOX (HOPX) EXPRESSION WAS SIGNIFICANTLY INCREASED IN CARDIOMYOCYTES TREATED WITH ARVS AND IN THE HEART TISSUE OF HIV PATIENTS. FURTHERMORE, WE FOUND THAT HOPX PLAYS A CRUCIAL ROLE IN ARVS MEDIATED CELLULAR HYPERTROPHY. MECHANISTICALLY, WE FOUND THAT HOPX PLAYS A CRITICAL ROLE IN EPIGENETIC REGULATION, THROUGH DEACETYLATION OF HISTONE, WHILE THE HDAC INHIBITOR, TRICHOSTATIN A, CAN RESTORE THE ACETYLATION LEVEL OF HISTONE 3 IN THE PRESENCE OF ARVS. 2021 7 1121 19 COMPARISON OF EPIGENETIC PROFILES OF HUMAN ORAL EPITHELIAL CELLS FROM HIV-POSITIVE (ON HAART) AND HIV-NEGATIVE SUBJECTS. HIV-INFECTED SUBJECTS ON HIGHLY ACTIVE ANTIRETROVIRAL THERAPY (HAART) ARE SUSCEPTIBLE TO COMORBID MICROBIAL INFECTIONS IN THE ORAL CAVITY. WE OBSERVED THAT PRIMARY ORAL EPITHELIAL CELLS (POECS) ISOLATED FROM HIV+ SUBJECTS ON HAART GROW MORE SLOWLY AND ARE LESS INNATE IMMUNE RESPONSIVE TO MICROBIAL CHALLENGE WHEN COMPARED WITH POECS FROM NORMAL SUBJECTS. THESE ABERRANT CELLS ALSO DEMONSTRATE EPIGENETIC DIFFERENCES THAT INCLUDE REDUCTION IN HISTONE DEACETYLASE 1 (HDAC-1) LEVELS AND REDUCED TOTAL DNA METHYLTRANSFERASE (DNMT) ACTIVITY SPECIFIC TO ENZYMES DNMT1 AND DNMT3A. THE DNMT ACTIVITY CORRELATES WELL WITH GLOBAL DNA METHYLATION, INDICATING THAT ABERRANT DNMT ACTIVITY IN HIV+ (ON HAART) POECS LEADS TO AN ABERRANTLY METHYLATED EPITHELIAL CELL PHENOTYPE. OVERALL, OUR RESULTS LEAD US TO HYPOTHESIZE THAT, IN PATIENTS WITH CHRONIC HIV INFECTION ON HAART, EPIGENETIC CHANGES IN KEY GENES RESULT IN INCREASED VULNERABILITY TO MICROBIAL INFECTION IN THE ORAL CAVITY. 2013 8 217 27 ACUTE EXERCISE INCREASES THE EXPRESSION OF KIR2DS4 BY PROMOTER DEMETHYLATION IN NK CELLS. POSITIVE EFFECTS OF EXERCISE ON CANCER PREVENTION AND PROGRESSION HAVE BEEN PROPOSED TO BE MEDIATED BY STIMULATING NATURAL KILLER (NK) CELLS. BECAUSE NK CELL RECEPTORS ARE REGULATED BY EPIGENETIC MODIFICATIONS, WE INVESTIGATED WHETHER ACUTE AEROBIC EXERCISE AND TRAINING CHANGE PROMOTER DNA METHYLATION AND GENE EXPRESSION OF THE ACTIVATING KIR2DS4 AND THE INHIBITING KIR3DL1 GENE. SIXTEEN HEALTHY WOMEN (50-60 YEARS) PERFORMED A GRADED EXERCISE TEST (GXT) AND WERE RANDOMIZED INTO EITHER A PASSIVE CONTROL GROUP OR AN INTERVENTION GROUP PERFORMING A FOUR-WEEK ENDURANCE EXERCISE INTERVENTION. BLOOD SAMPLES (PRE-, POST-GXT AND POST-TRAINING) WERE USED FOR ISOLATION OF DNA/RNA OF NK CELLS TO ASSESS DNA PROMOTER METHYLATION BY TARGETED DEEP-AMPLICON SEQUENCING AND GENE EXPRESSION BY QRT-PCR. POTENTIAL CHANGES IN NK CELL SUBSETS WERE DETERMINED BY FLOW CYTOMETRY. ACUTE AND CHRONIC EXERCISE DID NOT PROVOKE SIGNIFICANT ALTERATIONS OF NK CELL PROPORTIONS. PROMOTER METHYLATION DECREASED AND GENE EXPRESSION INCREASED FOR KIR2DS4 AFTER ACUTE EXERCISE. A HIGH GENE EXPRESSION CORRELATED WITH A LOW METHYLATION OF CPGS THAT WERE ALTERED BY ACUTE EXERCISE. CHRONIC EXERCISE RESULTED IN A MINOR DECREASE OF DNA METHYLATION AND DID NOT ALTER GENE EXPRESSION. ACUTE EXERCISE PROVOKES EPIGENETIC MODIFICATIONS, AFFECTING THE BALANCE BETWEEN THE ACTIVATING KIR2DS4 AND THE INHIBITING KIR3DL1, WITH POTENTIAL BENEFITS ON NK CELL FUNCTION. 2019 9 546 30 ATTENUATED EXPRESSION OF SLCO2A1 CAUSED BY DNA METHYLATION IN PEDIATRIC INFLAMMATORY BOWEL DISEASE. BACKGROUND: SLCO2A1 ENCODES A PROSTAGLANDIN (PG) TRANSPORTER, AND AUTOSOMAL RECESSIVE PATHOGENIC VARIANTS OF THIS GENE CAUSE CHRONIC ENTEROPATHY ASSOCIATED WITH SLCO2A1. IT IS UNCLEAR WHETHER A HETEROZYGOUS PATHOGENIC VARIANT OF SLCO2A1 HAS A ROLE IN THE PATHOGENESIS OF OTHER TYPES OF INFLAMMATORY BOWEL DISEASE (IBD). IN THIS STUDY, WE INVESTIGATED THE POSSIBLE INVOLVEMENT OF A LOCAL EPIGENETIC ALTERATION IN SLCO2A1 IN PATIENTS WITH A HETEROZYGOUS PATHOGENIC VARIANT. METHODS: WE CONDUCTED WHOLE-EXOME SEQUENCING OF SAMPLES FROM 2 SISTERS WITH SUSPECTED MONOGENIC IBD. IN ADDITION, WE PERFORMED BISULFITE SEQUENCING USING DNA EXTRACTED FROM THEIR SMALL AND LARGE INTESTINE SAMPLES TO EXPLORE EPIGENETIC ALTERATIONS. RESULTS: A HETEROZYGOUS SPLICING SITE VARIANT, SLCO2A1:C.940 + 1G > A, WAS DETECTED IN BOTH PATIENTS. TO EXPLORE THE POSSIBLE INVOLVEMENT OF EPIGENETIC ALTERATIONS, WE ANALYZED PROTEIN AND MESSENGER RNA EXPRESSION OF SLCO2A1, AND OBSERVED ATTENUATED SLCO2A1 EXPRESSION IN THE INFLAMED LESIONS OF THESE PATIENTS COMPARED WITH THAT IN THE CONTROL INDIVIDUALS. FURTHERMORE, BISULFITE SEQUENCING INDICATED DENSE METHYLATION IN THE PROMOTER REGION OF SLCO2A1 ONLY IN THE INFLAMED LESIONS OF BOTH PATIENTS. THE URINARY PG METABOLITE LEVELS IN THESE PATIENTS WERE COMPARABLE TO THOSE IN PATIENTS WITH CHRONIC ENTEROPATHY ASSOCIATED WITH SLCO2A1 AND HIGHER THAN THOSE IN THE CONTROL INDIVIDUALS. WE FOUND CONSIDERABLY HIGHER LEVELS OF THE METABOLITES IN PATIENT 1, WHO SHOWED MORE SEVERE SYMPTOMS THAN PATIENT 2. CONCLUSIONS: LOCAL DNA METHYLATION ATTENUATED SLCO2A1 EXPRESSION, WHICH MAY EVOKE LOCAL INFLAMMATION OF THE MUCOSA BY THE UNINCORPORATED PG. THESE FINDINGS MAY IMPROVE OUR UNDERSTANDING OF THE EPIGENETIC MECHANISMS UNDERLYING IBD DEVELOPMENT. 2023 10 407 24 ANALYSIS OF FOXP3+ REGULATORY T CELLS THAT DISPLAY APPARENT VIRAL ANTIGEN SPECIFICITY DURING CHRONIC HEPATITIS C VIRUS INFECTION. WE REPORTED PREVIOUSLY THAT A PROPORTION OF NATURAL CD25(+) CELLS ISOLATED FROM THE PBMC OF HCV PATIENTS CAN FURTHER UPREGULATE CD25 EXPRESSION IN RESPONSE TO HCV PEPTIDE STIMULATION IN VITRO, AND PROPOSED THAT VIRUS-SPECIFIC REGULATORY T CELLS (TREG) WERE PRIMED AND EXPANDED DURING THE DISEASE. HERE WE DESCRIBE EPIGENETIC ANALYSIS OF THE FOXP3 LOCUS IN HCV-RESPONSIVE NATURAL CD25(+) CELLS AND SHOW THAT THESE CELLS ARE NOT ACTIVATED CONVENTIONAL T CELLS EXPRESSING FOXP3, BUT HARD-WIRED TREG WITH A STABLE FOXP3 PHENOTYPE AND FUNCTION. OF APPROXIMATELY 46,000 GENES ANALYZED IN GENOME WIDE TRANSCRIPTION PROFILING, ABOUT 1% WERE DIFFERENTIALLY EXPRESSED BETWEEN HCV-RESPONSIVE TREG, HCV-NON-RESPONSIVE NATURAL CD25(+) CELLS AND CONVENTIONAL T CELLS. EXPRESSION PROFILES, INCLUDING CELL DEATH, ACTIVATION, PROLIFERATION AND TRANSCRIPTIONAL REGULATION, SUGGEST A SURVIVAL ADVANTAGE OF HCV-RESPONSIVE TREG OVER THE OTHER CELL POPULATIONS. SINCE NO TREG-SPECIFIC ACTIVATION MARKER IS KNOWN, WE TESTED 97 NS3-DERIVED PEPTIDES FOR THEIR ABILITY TO ELICIT CD25 RESPONSE (ASSUMING IT IS A SURROGATE MARKER), ACCOMPANIED BY HIGH RESOLUTION HLA TYPING OF THE PATIENTS. SOME REACTIVE PEPTIDES OVERLAPPED WITH PREVIOUSLY DESCRIBED EFFECTOR T CELL EPITOPES. OUR DATA OFFERS NEW INSIGHTS INTO HCV IMMUNE EVASION AND TOLERANCE, AND HIGHLIGHTS THE NON-SELF SPECIFIC NATURE OF TREG DURING INFECTION. 2009 11 6055 26 THE CXXC1 SUBUNIT OF THE TRITHORAX COMPLEX DIRECTS EPIGENETIC LICENSING OF CD4+ T CELL DIFFERENTIATION. DIFFERENT DYNAMICS OF GENE EXPRESSION ARE OBSERVED DURING CELL DIFFERENTIATION. IN T CELLS, GENES THAT ARE TURNED ON EARLY OR TURNED OFF AND STAY OFF HAVE BEEN THOROUGHLY STUDIED. HOWEVER, GENES THAT ARE INITIALLY TURNED OFF BUT THEN TURNED ON AGAIN AFTER STIMULATION HAS CEASED HAVE NOT BEEN DEFINED; THEY ARE OBVIOUSLY IMPORTANT, ESPECIALLY IN THE CONTEXT OF ACUTE VERSUS CHRONIC INFLAMMATION. USING THE TH1/TH2 DIFFERENTIATION PARADIGM, WE FOUND THAT THE CXXC1 SUBUNIT OF THE TRITHORAX COMPLEX DIRECTS TRANSCRIPTION OF GENES INITIALLY DOWN-REGULATED BY TCR STIMULATION BUT UP-REGULATED AGAIN IN A LATER PHASE. THE LATE UP-REGULATION OF THESE GENES WAS IMPAIRED EITHER BY PROLONGED TCR STIMULATION OR CXXC1 DEFICIENCY, WHICH LED TO DECREASED EXPRESSION OF TRIB3 AND KLF2 IN TH1 AND TH2 CELLS, RESPECTIVELY. LOSS OF CXXC1 RESULTED IN ENHANCED PATHOGENICITY IN ALLERGIC AIRWAY INFLAMMATION IN VIVO. THUS, CXXC1 PLAYS ESSENTIAL ROLES IN THE ESTABLISHMENT OF A PROPER CD4+ T CELL IMMUNE SYSTEM VIA EPIGENETIC CONTROL OF A SPECIFIC SET OF GENES. 2021 12 1763 25 EARLY TRANSCRIPTIONAL AND EPIGENETIC DIVERGENCE OF CD8+ T CELLS RESPONDING TO ACUTE VERSUS CHRONIC INFECTION. DURING A MICROBIAL INFECTION, RESPONDING CD8+ T CELLS GIVE RISE TO EFFECTOR CELLS THAT PROVIDE ACUTE HOST DEFENSE AND MEMORY CELLS THAT PROVIDE SUSTAINED PROTECTION. AN ALTERNATIVE OUTCOME IS EXHAUSTION, A STATE OF T CELL DYSFUNCTION THAT OCCURS IN THE CONTEXT OF CHRONIC INFECTIONS AND CANCER. ALTHOUGH IT IS EVIDENT THAT EXHAUSTED CD8+ T (TEX) CELLS ARE PHENOTYPICALLY AND MOLECULARLY DISTINCT FROM EFFECTOR AND MEMORY CD8+ T CELLS, THE FACTORS REGULATING THE EARLIEST EVENTS IN THE DIFFERENTIATION PROCESS OF TEX CELLS REMAIN INCOMPLETELY UNDERSTOOD. HERE, WE PERFORMED SINGLE-CELL RNA-SEQUENCING AND SINGLE-CELL ATAC-SEQUENCING OF CD8+ T CELLS RESPONDING TO LCMV-ARMSTRONG (LCMV-ARM) OR LCMV-CLONE 13 (LCMV-CL13), WHICH RESULT IN ACUTE OR CHRONIC INFECTIONS, RESPECTIVELY. COMPARED TO CD8+ T CELLS THAT HAD UNDERGONE THEIR FIRST DIVISION IN RESPONSE TO LCMV-ARM (DIV1ARM) CELLS, CD8+ T CELLS THAT HAD UNDERGONE THEIR FIRST DIVISION IN RESPONSE TO LCMV-CL13 (DIV1CL13) EXPRESSED HIGHER LEVELS OF GENES ENCODING TRANSCRIPTION FACTORS PREVIOUSLY ASSOCIATED WITH EXHAUSTION, ALONG WITH HIGHER LEVELS OF EZH2, THE CATALYTIC COMPONENT OF THE POLYCOMB REPRESSIVE COMPLEX 2 (PRC2) COMPLEX, WHICH MEDIATES EPIGENETIC SILENCING. MODULATION OF EZH2 RESULTED IN ALTERED EXPRESSION OF EXHAUSTION-ASSOCIATED MOLECULES BY CD8+ T CELLS RESPONDING TO LCMV-CL13, THOUGH THE SPECIFIC CELLULAR AND INFECTIOUS CONTEXTS, RATHER THAN SIMPLY THE LEVEL OF EZH2 EXPRESSION, LIKELY DETERMINE THE EVENTUAL OUTCOME. TAKEN TOGETHER, THESE FINDINGS SUGGEST THAT THE DIFFERENTIATION PATHS OF CD8+ T CELLS RESPONDING TO ACUTE VERSUS CHRONIC INFECTIONS MAY DIVERGE EARLIER THAN PREVIOUSLY APPRECIATED. 2023 13 5464 18 RESILIENCE IN LONG-TERM VIRAL INFECTION: GENETIC DETERMINANTS AND INTERACTIONS. VIRUS-INDUCED NEUROLOGICAL SEQUELAE RESULTING FROM INFECTION BY THEILER'S MURINE ENCEPHALOMYELITIS VIRUS (TMEV) ARE USED FOR STUDYING HUMAN CONDITIONS RANGING FROM EPILEPTIC SEIZURES TO DEMYELINATING DISEASE. MOUSE STRAINS ARE TYPICALLY CONSIDERED SUSCEPTIBLE OR RESISTANT TO TMEV INFECTION BASED ON VIRAL PERSISTENCE AND EXTREME PHENOTYPES, SUCH AS DEMYELINATION. WE HAVE IDENTIFIED A BROADER SPECTRUM OF PHENOTYPIC OUTCOMES BY INFECTING STRAINS OF THE GENETICALLY DIVERSE COLLABORATIVE CROSS (CC) MOUSE RESOURCE. WE EVALUATED THE CHRONIC-INFECTION GENE EXPRESSION PROFILES OF HIPPOCAMPI AND THORACIC SPINAL CORDS FOR 19 CC STRAINS IN RELATION TO PHENOTYPIC SEVERITY AND TMEV PERSISTENCE. STRAINS WERE CLUSTERED BASED ON SIMILAR PHENOTYPIC PROFILES AND TMEV LEVELS AT 90 DAYS POST-INFECTION, AND WE CATEGORIZED DISTINCT TMEV RESPONSE PROFILES. THE THREE MOST COMMON PROFILES INCLUDED "RESISTANT" AND "SUSCEPTIBLE," AS BEFORE, AS WELL AS A "RESILIENT" TMEV RESPONSE GROUP WHICH EXPERIENCED BOTH TMEV PERSISTENCE AND MILD NEUROLOGICAL PHENOTYPES EVEN AT 90 DAYS POST-INFECTION. EACH PROFILE HAD A DISTINCT GENE EXPRESSION SIGNATURE, ALLOWING THE IDENTIFICATION OF PATHWAYS AND NETWORKS SPECIFIC TO EACH TMEV RESPONSE GROUP. CC FOUNDER HAPLOTYPES FOR GENES INVOLVED IN THESE PATHWAYS/NETWORKS REVEALED CANDIDATE RESPONSE-SPECIFIC ALLELES. THESE ALLELES DEMONSTRATED PLEIOTROPY AND EPIGENETIC (MIRNA) REGULATION IN LONG-TERM TMEV INFECTION, WITH PARTICULAR RELEVANCE FOR RESILIENT MOUSE STRAINS. 2021 14 3468 39 HYPOXIA-INDUCED DNA HYPERMETHYLATION IN HUMAN PULMONARY FIBROBLASTS IS ASSOCIATED WITH THY-1 PROMOTER METHYLATION AND THE DEVELOPMENT OF A PRO-FIBROTIC PHENOTYPE. BACKGROUND: PULMONARY FIBROSIS IS A DEBILITATING AND LETHAL DISEASE WITH NO EFFECTIVE TREATMENT OPTIONS. UNDERSTANDING THE PATHOLOGICAL PROCESSES AT PLAY WILL DIRECT THE APPLICATION OF NOVEL THERAPEUTIC AVENUES. HYPOXIA HAS BEEN IMPLICATED IN THE PATHOGENESIS OF PULMONARY FIBROSIS YET THE PRECISE MECHANISM BY WHICH IT CONTRIBUTES TO DISEASE PROGRESSION REMAINS TO BE FULLY ELUCIDATED. IT HAS BEEN SHOWN THAT CHRONIC HYPOXIA CAN ALTER DNA METHYLATION PATTERNS IN TUMOUR-DERIVED CELL LINES. THIS EPIGENETIC ALTERATION CAN INDUCE CHANGES IN CELLULAR PHENOTYPE WITH PROMOTER METHYLATION BEING ASSOCIATED WITH GENE SILENCING. OF PARTICULAR RELEVANCE TO IDIOPATHIC PULMONARY FIBROSIS (IPF) IS THE OBSERVATION THAT THY-1 PROMOTER METHYLATION IS ASSOCIATED WITH A MYOFIBROBLAST PHENOTYPE WHERE LOSS OF THY-1 OCCURS ALONGSIDE INCREASED ALPHA SMOOTH MUSCLE ACTIN (ALPHA-SMA) EXPRESSION. THE INITIAL AIM OF THIS STUDY WAS TO DETERMINE WHETHER HYPOXIA REGULATES DNA METHYLATION IN NORMAL HUMAN LUNG FIBROBLASTS (CCD19LU). AS IT HAS BEEN REPORTED THAT HYPOXIA SUPPRESSES THY-1 EXPRESSION DURING LUNG DEVELOPMENT WE ALSO STUDIED THE EFFECT OF HYPOXIA ON THY-1 PROMOTER METHYLATION AND GENE EXPRESSION. METHODS: CCD19LU WERE GROWN FOR UP TO 8 DAYS IN HYPOXIA AND ASSESSED FOR GLOBAL CHANGES IN DNA METHYLATION USING FLOW CYTOMETRY. REAL-TIME PCR WAS USED TO QUANTIFY EXPRESSION OF THY-1, ALPHA-SMA, COLLAGEN I AND III. GENOMIC DNA WAS BISULPHITE TREATED AND METHYLATION SPECIFIC PCR (MSPCR) WAS USED TO EXAMINE THE METHYLATION STATUS OF THE THY-1 PROMOTER. RESULTS: SIGNIFICANT GLOBAL HYPERMETHYLATION WAS DETECTED IN HYPOXIC FIBROBLASTS RELATIVE TO NORMOXIC CONTROLS AND WAS ACCOMPANIED BY INCREASED EXPRESSION OF MYOFIBROBLAST MARKERS. THY-1 MRNA EXPRESSION WAS SUPPRESSED IN HYPOXIC CELLS, WHICH WAS RESTORED WITH THE DEMETHYLATING AGENT 5-AZA-2'-DEOXYCYTIDINE. MSPCR REVEALED THAT THY-1 BECAME METHYLATED FOLLOWING FIBROBLAST EXPOSURE TO 1% O2. CONCLUSION: THESE DATA SUGGEST THAT GLOBAL AND GENE-SPECIFIC CHANGES IN DNA METHYLATION MAY PLAY AN IMPORTANT ROLE IN FIBROBLAST FUNCTION IN HYPOXIA. 2012 15 2967 34 GENETIC AND EPIGENETIC REGULATION OF CATECHOL-O-METHYLTRANSFERASE IN RELATION TO INFLAMMATION IN CHRONIC FATIGUE SYNDROME AND FIBROMYALGIA. BACKGROUND: CATECHOL-O-METHYLTRANSFERASE (COMT) HAS BEEN SHOWN TO INFLUENCE CLINICAL PAIN, DESCENDING MODULATION, AND EXERCISE-INDUCED SYMPTOM WORSENING. COMT REGULATES NOCICEPTIVE PROCESSING AND INFLAMMATION, KEY PATHOPHYSIOLOGICAL FEATURES OF CHRONIC FATIGUE SYNDROME AND FIBROMYALGIA (CFS/FM). WE AIMED TO DETERMINE THE INTERACTIONS BETWEEN GENETIC AND EPIGENETIC MECHANISMS REGULATING COMT AND ITS INFLUENCE ON INFLAMMATORY MARKERS AND SYMPTOMS IN PATIENTS WITH CFS/FM. METHODS: A CASE-CONTROL STUDY WITH REPEATED-MEASURES DESIGN WAS USED TO REDUCE THE CHANCE OF FALSE POSITIVE AND INCREASE THE POWER OF OUR FINDINGS. FIFTY-FOUR PARTICIPANTS (28 PATIENTS WITH CFS/FM AND 26 CONTROLS) WERE ASSESSED TWICE WITHIN 4 DAYS. THE ASSESSMENT INCLUDED CLINICAL QUESTIONNAIRES, NEUROPHYSIOLOGICAL ASSESSMENT (PAIN THRESHOLDS, TEMPORAL SUMMATION, AND CONDITIONED PAIN MODULATION), AND BLOOD WITHDRAWAL IN ORDER TO ASSESS RS4818, RS4633, AND RS4680 COMT POLYMORPHISMS AND PERFORM HAPLOTYPE ESTIMATION, DNA METHYLATION IN THE COMT GENE (BOTH MB-COMT AND S-COMT PROMOTERS), AND CYTOKINE EXPRESSION (TNF-ALPHA, IFN-GAMMA, IL-6, AND TGF-BETA). RESULTS: COMT HAPLOTYPES WERE ASSOCIATED WITH DNA METHYLATION IN THE S-COMT PROMOTER, TGF-BETA EXPRESSION, AND SYMPTOMS. HOWEVER, THIS WAS NOT SPECIFIC FOR ONE CONDITION. SIGNIFICANT BETWEEN-GROUP DIFFERENCES WERE FOUND FOR INCREASED DNA METHYLATION IN THE MB-COMT PROMOTER AND DECREASED IFN-GAMMA EXPRESSION IN PATIENTS. DISCUSSION: OUR RESULTS ARE CONSISTENT WITH BASIC AND CLINICAL RESEARCH, PROVIDING INTERESTING INSIGHTS INTO GENETIC-EPIGENETIC REGULATORY MECHANISMS. MB-COMT DNA METHYLATION MIGHT BE AN INDEPENDENT FACTOR CONTRIBUTING TO THE PATHOPHYSIOLOGY OF CFS/FM. FURTHER RESEARCH ON DNA METHYLATION IN COMPLEX CONDITIONS SUCH AS CFS/FM IS WARRANTED. WE RECOMMEND FUTURE RESEARCH TO EMPLOY A REPEATED-MEASURE DESIGN TO CONTROL FOR BIOMARKERS VARIABILITY AND WITHIN-SUBJECT CHANGES. 2022 16 2730 39 EXPLORING THE BIOLOGICAL FUNCTION OF IMMUNE CELL-RELATED GENES IN HUMAN IMMUNODEFICIENCY VIRUS (HIV)-1 INFECTION BASED ON WEIGHTED GENE CO-EXPRESSION NETWORK ANALYSIS (WGCNA). BACKGROUND: ACQUIRED IMMUNODEFICIENCY SYNDROME (AIDS) IS A CHRONIC INFECTIOUS DISEASE CHARACTERIZED BY CONSISTENT IMMUNE DYSFUNCTION. THE OBJECTIVE OF THIS STUDY IS TO DETERMINE WHETHER IMMUNE CELL-RELATED GENES CAN BE USED AS BIOMARKERS FOR THE OCCURRENCE OF AIDS AND POTENTIAL MOLECULAR MECHANISMS. METHODS: A WEIGHTED GENE CO-EXPRESSION NETWORK ANALYSIS WAS PERFORMED USING THE GSE6740 DATASET FROM THE GENE EXPRESSION SYNTHESIS DATABASE TO IDENTIFY THE HUB GENE, WHICH CONTAINED MICROARRAY DATA FROM HIV-1 POSITIVE (HIV-1(+)) AND HIV-1 NEGATIVE (HIV-1(-)) INDIVIDUALS. THE HIV-1(+)-RELATED DIFFERENTIALLY EXPRESSED GENES WERE THEN IDENTIFIED USING THE LIMMA PACKAGE. SUBSEQUENTLY, THE CHARACTERISTIC IMMUNE CELL-RELATED GENES WERE IDENTIFIED AS DIAGNOSTIC BIOMARKERS FOR HIV-1(+) USING THE RANDOM FOREST MODEL (RF), SUPPORT VECTOR MACHINE MODEL, AND GENERALIZED LINEAR MODEL. RESULTS: MEDARKGREEN EXHIBITED THE STRONGEST CORRELATION WITH HIV CLINICAL FEATURES OF ANY OF THESE MODULES. AS THE BEST MODEL FOR DIAGNOSING HIV-1(+/-), RF WAS USED TO SELECT FOUR CRITICAL IMMUNE CELL-RELATED GENES, NAMELY, ARRB1, DPEP2, LTBP3, AND RGCC, AND A NOMOGRAM MODEL WAS CREATED TO PREDICT THE OCCURRENCE OF HIV-1 INFECTION BASED ON FOUR KEY IMMUNE CELL-RELATED GENES. DIAGNOSTIC GENES WERE SHOWN TO BE ENGAGED IN IMMUNE-RELATED PATHWAYS, SUGGESTING THAT IMMUNOLOGICAL MOLECULES, IMMUNE CELLS, AND IMMUNE PATHWAYS ALL HAVE A ROLE IN HIV-1 INFECTION. THE CTD DATABASE WAS EXPLORED FOR PROSPECTIVE MEDICATIONS OR MOLECULAR COMPOUNDS THAT MIGHT BE UTILIZED TO TREAT HIV-1(+) PATIENTS. = MOREOVER, IN HIV-1(+) INDIVIDUALS, THE CERNA NETWORK REVEALED THAT ARRB1, DPEP2, LTBP3, AND RGCC COULD BE REGULATED BY LNCRNAS THROUGH THE CORRESPONDING MIRNAS. ULTIMATELY, RT-PCR RESULTS FROM CLINICAL BLOOD SAMPLES DEMONSTRATED THAT THE FOUR DIAGNOSTIC GENES WERE SIGNIFICANTLY DOWNREGULATED IN HIV-1(+) PATIENTS. CONCLUSION: WE SCREENED FOUR IMMUNE CELL-RELATED GENES, ARRB1, DPEP2, LTBP3, AND RGCC, WHICH MAY BE CONSIDERED AS THE DIAGNOSTIC MARKERS FOR HIV-1/AIDS. OUR FINDINGS REVEAL THAT IMMUNE RELATED GENES AND PATHWAYS INVOLVED IN HIV-1 PATHOGENESIS WERE REGULATED ON BOTH GENETIC AND EPIGENETIC LEVELS BY CONSTRUCTING A CERNA NETWORK ASSOCIATED WITH LNCRNA. 2022 17 276 19 AGE-RELATED DIFFERENCES IN MONOCYTE DNA METHYLATION AND IMMUNE FUNCTION IN HEALTHY KENYAN ADULTS AND CHILDREN. BACKGROUND: AGE-RELATED CHANGES IN ADAPTIVE AND INNATE IMMUNE CELLS HAVE BEEN ASSOCIATED WITH A DECLINE IN EFFECTIVE IMMUNITY AND CHRONIC, LOW-GRADE INFLAMMATION. EPIGENETIC, TRANSCRIPTIONAL, AND FUNCTIONAL CHANGES IN MONOCYTES OCCUR WITH AGING, THOUGH MOST STUDIES TO DATE HAVE FOCUSED ON DIFFERENCES BETWEEN YOUNG ADULTS AND THE ELDERLY IN POPULATIONS WITH EUROPEAN ANCESTRY; FEW DATA EXIST REGARDING CHANGES THAT OCCUR IN CIRCULATING MONOCYTES DURING THE FIRST FEW DECADES OF LIFE OR IN AFRICAN POPULATIONS. WE ANALYZED DNA METHYLATION PROFILES, CYTOKINE PRODUCTION, AND INFLAMMATORY GENE EXPRESSION PROFILES IN MONOCYTES FROM YOUNG ADULTS AND CHILDREN FROM WESTERN KENYA. RESULTS: WE IDENTIFIED SEVERAL HYPO- AND HYPER-METHYLATED CPG SITES IN MONOCYTES FROM KENYAN YOUNG ADULTS VS. CHILDREN THAT REPLICATED FINDINGS IN THE CURRENT LITERATURE OF DIFFERENTIAL DNA METHYLATION IN MONOCYTES FROM ELDERLY PERSONS VS. YOUNG ADULTS ACROSS DIVERSE POPULATIONS. DIFFERENTIALLY METHYLATED CPG SITES WERE ALSO NOTED IN GENE REGIONS IMPORTANT TO INFLAMMATION AND INNATE IMMUNE RESPONSES. MONOCYTES FROM KENYAN YOUNG ADULTS VS. CHILDREN DISPLAYED INCREASED PRODUCTION OF IL-8, IL-10, AND IL-12P70 IN RESPONSE TO TLR4 AND TLR2/1 STIMULATION AS WELL AS DISTINCT INFLAMMATORY GENE EXPRESSION PROFILES. CONCLUSIONS: THESE FINDINGS COMPLEMENT PREVIOUS REPORTS OF AGE-RELATED METHYLATION CHANGES IN ISOLATED MONOCYTES AND PROVIDE NOVEL INSIGHTS INTO THE ROLE OF AGE-ASSOCIATED CHANGES IN INNATE IMMUNE FUNCTIONS. 2021 18 1584 17 DNA METHYLATION PROFILES OF SELECTED PRO-INFLAMMATORY CYTOKINES IN ALZHEIMER DISEASE. BY MEANS OF FUNCTIONAL GENOMICS ANALYSIS, WE RECENTLY DESCRIBED THE MRNA EXPRESSION PROFILES OF VARIOUS GENES INVOLVED IN THE NEUROINFLAMMATORY RESPONSE IN THE BRAINS OF SUBJECTS WITH LATE-ONSET ALZHEIMER DISEASE (LOAD). SOME OF THESE GENES, NAMELY INTERLEUKIN (IL)-1BETA AND IL-6, SHOWED DISTINCT EXPRESSION PROFILES WITH PEAK EXPRESSION DURING THE FIRST STAGES OF THE DISEASE AND CONTROL-LIKE LEVELS AT LATER STAGES. IL-1BETA AND IL-6 GENES ARE MODULATED BY DNA METHYLATION IN DIFFERENT CHRONIC AND DEGENERATIVE DISEASES; IT IS ALSO WELL KNOWN THAT LOAD MAY HAVE AN EPIGENETIC BASIS. INDEED, WE AND OTHERS HAVE PREVIOUSLY REPORTED GENE-SPECIFIC DNA METHYLATION ALTERATIONS IN LOAD AND IN RELATED ANIMAL MODELS. BASED ON THESE DATA, WE STUDIED THE DNA METHYLATION PROFILES, AT SINGLE CYTOSINE RESOLUTION, OF IL-1BETA AND IL-6 5'-FLANKING REGION BY BISULPHITE MODIFICATION IN THE CORTEX OF HEALTHY CONTROLS AND LOAD PATIENTS AT 2 DIFFERENT DISEASE STAGES: BRAAK I-II/A AND BRAAK V-VI/C. OUR ANALYSIS PROVIDES EVIDENCE THAT NEUROINFLAMMATION IN LOAD IS ASSOCIATED WITH (AND POSSIBLY MEDIATED BY) EPIGENETIC MODIFICATIONS. 2017 19 2200 34 EPIGENETIC MODIFICATION OF FOXP3 IN PATIENTS WITH CHRONIC HIV INFECTION. OBJECTIVES: HIV-1 MODULATES HOST CELL EPIGENETIC MACHINERY TO CONTROL ITS OWN REPLICATION AND INDUCE IMMUNE SUPPRESSION. HIV-1 INFECTION LEADS TO ACTIVATION OF T REGULATORY CELL (T(REG)), BUT THE MECHANISM UNDERLYING THIS IMMUNE MODULATION IS UNCLEAR. T(REG) PLAYS A PROMINENT ROLE IN GUT-MUCOSAL IMMUNE TOLERANCE BY RESTRAINING EXCESSIVE EFFECTOR T-CELL RESPONSES, A MECHANISM THAT IS KNOWN TO BE DISTURBED IN CHRONIC HIV-1 INFECTION. DNA METHYLATION PLAYS A MAJOR ROLE IN T(REG) LINEAGE COMMITMENT AND IMMUNE HOMEOSTASIS, WHICH MAY BE REGULATED BY HIV. TO INVESTIGATE THE MECHANISMS OF ABERRANT METHYLATION OF THE T(REG) MARKER FOXP3 IN HIV-1 INFECTION, WE EVALUATED THE EXPRESSION PATTERN OF METHYLATION-RELATED ENZYMES AND ITS CORRELATION TO FOXP3 METHYLATION. METHODS: FOXP3 PROMOTER METHYLATION IN THE COLON MUCOSA AND PERIPHERAL BLOOD FROM HIV-INFECTED PATIENTS AND CONTROL SUBJECTS WAS MEASURED USING PYROSEQUENCING. GENE EXPRESSION PATTERN OF DNA METHYLATION ENZYMES IN THE COLON MUCOSA WAS INVESTIGATED BY MICROARRAY AND QUANTITATIVE REVERSE TRANSCRIPTASE-POLYMERASE CHAIN REACTION ANALYSIS IN THE SAME SUBJECTS. RESULTS: FOXP3 PROMOTER WAS SIGNIFICANTLY (P