1  4596 142 NATURAL KILLER CELLS IN HUMAN IMMUNODEFICIENCY VIRUS-1 INFECTION: SPOTLIGHT ON THE IMPACT OF HUMAN CYTOMEGALOVIRUS. HUMAN CYTOMEGALOVIRUS (HCMV) HAS BEEN CLOSELY ASSOCIATED WITH THE HUMAN RACE ACROSS EVOLUTIONARY TIME. HCMV CO-INFECTION IS NEARLY UNIVERSAL IN HUMAN IMMUNODEFICIENCY VIRUS-1 (HIV-1)-INFECTED INDIVIDUALS AND REMAINS AN IMPORTANT COFACTOR IN HIV-1 DISEASE PROGRESSION EVEN IN THE ERA OF EFFECTIVE ANTIRETROVIRAL TREATMENT. HCMV INFECTION HAS BEEN SHOWN TO HAVE A BROAD AND POTENT INFLUENCE ON THE HUMAN IMMUNE SYSTEM AND HAS BEEN LINKED WITH THE DISCOVERY AND CHARACTERIZATION OF ADAPTIVE NATURAL KILLER (NK) CELLS. DISTINCT NK-CELL SUBSETS, PREDOMINATELY EXPRESSING THE ACTIVATING RECEPTOR NKG2C AND THE MARKER OF TERMINAL DIFFERENTIATION CD57, EXPAND IN RESPONSE TO HCMV. THESE NK-CELL POPULATIONS ENGAGED IN THE LONG-LASTING INTERACTION WITH HCMV, IN ADDITION TO CHARACTERISTIC BUT VARIABLE EXPRESSION OF SURFACE RECEPTORS, EXHIBIT REDUCED EXPRESSION OF SIGNALING PROTEINS AND TRANSCRIPTION FACTORS EXPRESSED BY CANONICAL NK CELLS. BROAD EPIGENETIC MODIFICATIONS DRIVE THE EMERGENCE AND PERSISTENCE OF HCMV-ADAPTED NK CELLS THAT HAVE DISTINCT FUNCTIONAL CHARACTERISTICS. NKG2C(+) NK-CELL EXPANSIONS HAVE BEEN OBSERVED IN HIV-1 INFECTED PATIENTS AND OTHER ACUTE AND CHRONIC VIRAL INFECTIONS BEING SYSTEMATICALLY ASSOCIATED WITH HCMV SEROPOSITIVITY. THE LATTER IS POTENTIALLY AN IMPORTANT CONFOUNDING VARIABLE IN STUDIES FOCUSED ON THE CELLULAR NK-CELL RECEPTOR REPERTOIRE AND FUNCTIONAL CAPACITY. HERE, FOCUSING ON HIV-1 INFECTION WE REVIEW THE EVIDENCE IN FAVOR OF "ADAPTIVE" CHANGES LIKELY INDUCED BY HCMV CO-INFECTION IN NK-CELL SUBSETS. WE HIGHLIGHT A NUMBER OF KEY QUESTIONS AND HOW INSIGHTS INTO THE ADAPTIVE BEHAVIOR OF NK CELLS WILL INFORM NEW STRATEGIES EXPLOITING THEIR UNIQUE PROPERTIES IN THE FIGHT AGAINST HIV-1.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
2  1735  40 EARLY AND SUSTAINED EXPANSION OF ADAPTIVE NATURAL KILLER CELLS FOLLOWING HAPLOIDENTICAL TRANSPLANTATION AND CTLA4IG-PRIMED DONOR LYMPHOCYTE INFUSIONS DISSOCIATE GRAFT-VERSUS-LEUKEMIA AND GRAFT-VERSUS-HOST EFFECTS. BACKGROUND: ADAPTIVE OR MEMORY NATURAL KILLER (NK) CELLS WITH EPIGENETIC IMPRINTS SIMILAR TO MEMORY T CELLS HAVE BEEN SHOWN TO DEVELOP IN RESPONSE TO CYTOMEGALOVIRUS (CMV) INFECTION WITH UPREGULATION OF ACTIVATING RECEPTOR NKG2C. THESE CELLS HAVE BEEN SHOWN TO POSSESS STRONG ANTI-TUMOUR EFFICACY BOTH IN-VITRO AS WELL AS IN-VIVO. OBJECTIVES: TO DETERMINE IF RECONSTITUTION OF ADAPTIVE NK CELLS (CD56(DIM)NKG2C(+)NKG2A(-)) IN PATIENTS WITH ADVANCED LEUKEMIA UNDERGOING HAPLOIDENTICAL HCT HAD ANY IMPACT ON DISEASE PROGRESSION (DP). STUDY DESIGN: THE STUDY COHORT COMPRISED OF 60 PATIENTS WITH ADVANCED ACUTE LEUKEMIA, AGED 2-65 YEARS, RECEIVING MYELOABLATIVE PTCY BASED HAPLOIDENTICAL TRANSPLANTATION FROM CMV SEROPOSITIVE DONORS, FOLLOWED BY CTLA4IG-PRIMED DONOR LYMPHOCYTE INFUSIONS (DLI). THEY WERE EVALUATED FOR THE KINETICS OF RECONSTITUTION OF ADAPTIVE NK CELLS, BOTH PHENOTYPIC AND FUNCTIONAL, AT DAYS +30,+60, +90 AND AT REGULAR INTERVALS, TO 3 YEARS OF FOLLOW-UP, IN RELATION TO DP. RECONSTITUTION OF ADAPTIVE NK CELLS WAS COMPARED WITH A RETROSPECTIVE COHORT OF PATIENTS IN THE SAME PROTOCOL RECEIVING DLI WITHOUT CTLA4IG. RESULTS: NON-RELAPSE MORTALITY, ACUTE AND CHRONIC GVHD WERE 5.1%, 10.3% AND 14.5%. DP WAS 17.5% AT A MEDIAN FOLLOW-UP OF 28 MONTHS. ADAPTIVE NK CELLS WERE SIGNIFICANTLY HIGHER IN PATIENTS WITHOUT DP AT DAYS+30, +60 AND +90 (P = 0.0001), IRRESPECTIVE OF CMV REACTIVATION AND REMAINED ELEVATED UNTIL 36 MONTHS POST-HCT. THESE CELLS MAINTAINED THEIR FUNCTIONAL COMPETENCE AS MEASURED BY ROBUST INTERFERON-GAMMA PRODUCTION WITH HIGHER EXPRESSIONS OF KIR, NKG2D AND CD57, WITHOUT ANY INCREASE IN PD1 EXPRESSION. GRAFTS FROM DONORS WITH HIGHER ADAPTIVE NK CELLS WERE ASSOCIATED WITH A LOWER RISK OF DP (P = 0.0001). IN MULTIVARIATE ANALYSIS, ADAPTIVE NK CELL RECOVERY AT DAY +90 HAD THE MOST FAVORABLE IMPACT ON DP (HR-0.7). TREGS RECONSTITUTED BRISKLY ALONG WITH THE ADAPTIVE NK CELLS AND WERE SUSTAINED AS WELL, WITHOUT COMPROMISING THE GVL EFFECT. COMPARISON WITH A RETROSPECTIVE COHORT RECEIVING THE SAME PROTOCOL WITH DLI WITHOUT CTLA4IG, SHOWED A SUPERIOR RECONSTITUTION OF ADAPTIVE NK CELLS IN THOSE RECEIVING CTLA4IG-DLI (P < 0.0001). CONCLUSION: OUR STUDY SUGGESTS THAT MYELOABLATIVE TRANSPLANTATION FROM CMV SEROPOSITIVE HAPLOIDENTICAL DONORS AUGMENTED WITH CTLA4IG-PRIMED DLI MIGHT FAVOR EARLY AND SUSTAINED EXPANSION OF FUNCTIONALLY COMPETENT ADAPTIVE NK CELLS IRRESPECTIVE OF CMV REACTIVATION, WITH A FAVORABLE OUTCOME.	2021	

3   991  37 CHRONIC STIMULATION DRIVES HUMAN NK CELL DYSFUNCTION AND EPIGENETIC REPROGRAMING. A POPULATION OF NATURAL KILLER (NK) CELLS EXPRESSING THE ACTIVATING RECEPTOR NKG2C AND THE MATURATION MARKER CD57 EXPANDS IN RESPONSE TO HUMAN CYTOMEGALOVIRUS (HCMV) INFECTION. CD3-CD56DIMCD57+NKG2C+ NK CELLS ARE SIMILAR TO CD8+ MEMORY T CELLS WITH RAPID AND ROBUST EFFECTOR FUNCTION UPON RE-STIMULATION, PERSISTENCE, AND EPIGENETIC REMODELING OF THE IFNG LOCUS. CHRONIC ANTIGEN STIMULATION DRIVES CD8+ MEMORY T CELL PROLIFERATION WHILE ALSO INDUCING GENOME-WIDE EPIGENETIC REPROGRAMING AND DYSFUNCTION. WE HYPOTHESIZED THAT CHRONIC STIMULATION COULD SIMILARLY INDUCE EPIGENETIC REPROGRAMING AND DYSFUNCTION IN NK CELLS. HERE WE SHOW THAT CHRONIC STIMULATION OF ADAPTIVE NK CELLS THROUGH NKG2C USING PLATE-BOUND AGONISTIC ANTIBODIES IN COMBINATION WITH IL-15 DROVE ROBUST PROLIFERATION AND ACTIVATION OF CD3-CD56DIMCD57+NKG2C+ NK CELLS WHILE SIMULTANEOUSLY INDUCING HIGH EXPRESSION OF THE CHECKPOINT INHIBITORY RECEPTORS LAG-3 AND PD-1. MARKED INDUCTION OF CHECKPOINT INHIBITORY RECEPTORS WAS ALSO OBSERVED ON THE SURFACE OF ADAPTIVE NK CELLS CO-CULTURED WITH HCMV-INFECTED ENDOTHELIAL CELLS. CHRONICALLY STIMULATED ADAPTIVE NK CELLS WERE DYSFUNCTIONAL WHEN CHALLENGED WITH TUMOR TARGETS. THESE CELLS EXHIBITED A PATTERN OF EPIGENETIC REPROGRAMING, WITH GENOME-WIDE ALTERATIONS IN DNA METHYLATION. OUR STUDY HAS IMPORTANT IMPLICATIONS FOR CANCER IMMUNOTHERAPY AND SUGGEST THAT EXHAUSTED NK CELLS COULD BE TARGETED WITH INHIBITORY CHECKPOINT RECEPTOR BLOCKADE.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
4   466  21 ARE THE HEALTHY VULNERABLE? CYTOMEGALOVIRUS SEROPOSITIVITY IN HEALTHY ADULTS IS ASSOCIATED WITH ACCELERATED EPIGENETIC AGE AND IMMUNE DYSREGULATION. BACKGROUND: EVALUATING AGE AS A RISK FACTOR FOR SUSCEPTIBILITY TO INFECTIOUS DISEASES, PARTICULARLY CORONAVIRUS DISEASE 2019 (COVID-19), IS CRITICAL. CYTOMEGALOVIRUS (CMV) SEROLOGIC PREVALENCE INCREASES WITH AGE AND ASSOCIATES WITH INFLAMMATORY-MEDIATED DISEASES IN THE ELDERLY. HOWEVER, LITTLE IS KNOWN REGARDING THE SUBCLINICAL IMPACT OF CMV AND RISK IT POSES TO HEALTHY OLDER ADULTS. PRIOR TO THE COVID-19 PANDEMIC WE CONDUCTED A STUDY TO DETERMINE THE ASSOCIATION OF CMV TO BIOLOGIC AGE AND IMMUNE DYSREGULATION. METHODS: COMMUNITY-DWELLING, HEALTHY ADULTS OLDER THAN 60 YEARS WERE EVALUATED USING DNA METHYLATION ASSAYS TO DEFINE EPIGENETIC AGE (EPIAGE) AND T-CELL IMMUNOPHENOTYPING TO ASSESS IMMUNE DYSREGULATION. RESULTS: ALL SUBJECTS WERE HEALTHY AND ASYMPTOMATIC. THOSE CMV SEROPOSITIVE HAD MORE LYMPHOCYTES, CD8 T CELLS, CD28- T CELLS, DECREASED CD4:CD8 CELL RATIOS, AND HAD HIGHER AVERAGE EPIAGE (65.34 YEARS) THAN THOSE CMV SERONEGATIVE (59.53 YEARS). DECREASED PERCENT CD4 (P = .003) AND NUMBERS OF CD4 T CELLS (P = .0199) CORRELATED WITH INCREASED EPIAGE. CONCLUSIONS: OUR NOVEL FINDINGS DISTINGUISH ALTERED IMMUNITY IN THE ELDERLY BASED ON CMV STATUS. CHRONIC CMV INFECTION IN HEALTHY, OLDER ADULTS IS ASSOCIATED WITH INDICATORS OF IMMUNE DYSREGULATION, BOTH OF WHICH CORRELATE TO DIFFERENCES IN EPIAGE.	2022	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
5  6481  36 TOX IS EXPRESSED BY EXHAUSTED AND POLYFUNCTIONAL HUMAN EFFECTOR MEMORY CD8(+) T CELLS. CD8(+) T CELL EXHAUSTION IS A HALLMARK OF MANY CANCERS AND CHRONIC INFECTIONS. IN MICE, T CELL FACTOR 1 (TCF-1) MAINTAINS EXHAUSTED CD8(+) T CELL RESPONSES, WHEREAS THYMOCYTE SELECTION-ASSOCIATED HMG BOX (TOX) IS REQUIRED FOR THE EPIGENETIC REMODELING AND SURVIVAL OF EXHAUSTED CD8(+) T CELLS. HOWEVER, IT HAS REMAINED UNCLEAR TO WHAT EXTENT THESE TRANSCRIPTION FACTORS PLAY ANALOGOUS ROLES IN HUMANS. IN THIS STUDY, WE MAPPED THE EXPRESSION OF TOX AND TCF-1 AS A FUNCTION OF DIFFERENTIATION AND SPECIFICITY IN THE HUMAN CD8(+) T CELL LANDSCAPE. HERE, WE DEMONSTRATE THAT CIRCULATING TOX(+) CD8(+) T CELLS EXIST IN MOST HUMANS, BUT THAT TOX IS NOT EXCLUSIVELY ASSOCIATED WITH EXHAUSTION. EFFECTOR MEMORY CD8(+) T CELLS GENERALLY EXPRESSED TOX, WHEREAS NAIVE AND EARLY-DIFFERENTIATED MEMORY CD8(+) T CELLS GENERALLY EXPRESSED TCF-1. CYTOLYTIC GENE AND PROTEIN EXPRESSION SIGNATURES WERE ALSO DEFINED BY THE EXPRESSION OF TOX. IN THE CONTEXT OF A RELENTLESS IMMUNE CHALLENGE, EXHAUSTED HIV-SPECIFIC CD8(+) T CELLS COMMONLY EXPRESSED TOX, OFTEN IN CLUSTERS WITH VARIOUS ACTIVATION MARKERS AND INHIBITORY RECEPTORS, AND EXPRESSED LESS TCF-1. HOWEVER, POLYFUNCTIONAL MEMORY CD8(+) T CELLS SPECIFIC FOR CYTOMEGALOVIRUS (CMV) OR EPSTEIN-BARR VIRUS (EBV) ALSO EXPRESSED TOX, EITHER WITH OR WITHOUT TCF-1. A SIMILAR PHENOTYPE WAS OBSERVED AMONG HIV-SPECIFIC CD8(+) T CELLS FROM INDIVIDUALS WHO MAINTAINED EXCEPTIONAL IMMUNE CONTROL OF VIRAL REPLICATION. COLLECTIVELY, THESE DATA DEMONSTRATE THAT TOX IS EXPRESSED BY MOST CIRCULATING EFFECTOR MEMORY CD8(+) T CELL SUBSETS AND NOT EXCLUSIVELY LINKED TO EXHAUSTION.	2020	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
6  1267  33 CYTOMEGALOVIRUS INFECTION ACCELERATES EPIGENETIC AGING. EPIGENETIC MECHANISMS SUCH AS DNA METHYLATION (DNAM) HAVE A CENTRAL ROLE IN THE REGULATION OF GENE EXPRESSION AND THEREBY IN CELLULAR DIFFERENTIATION AND TISSUE HOMEOSTASIS. IT HAS RECENTLY BEEN SHOWN THAT AGING IS ASSOCIATED WITH PROFOUND CHANGES IN DNAM. SEVERAL OF THESE METHYLATION CHANGES TAKE PLACE IN A CLOCK-LIKE FASHION, I.E. CORRELATING WITH THE CALENDAR AGE OF AN INDIVIDUAL. THUS, THE EPIGENETIC CLOCK BASED ON THESE KIND OF DNAM CHANGES COULD PROVIDE A NEW BIOMARKER FOR HUMAN AGING PROCESS, I.E. BEING ABLE TO SEPARATE THE CALENDAR AND BIOLOGICAL AGE. INFORMATION ABOUT THE CORRELATION OF THE TIME INDICATED BY THIS CLOCK TO THE VARIOUS ASPECTS OF IMMUNOSENESCENCE IS STILL MISSING. AS CHRONIC CYTOMEGALOVIRUS (CMV) INFECTION IS PROBABLY ONE OF THE MAJOR DRIVING FORCES OF IMMUNOSENESCENCE, WE NOW HAVE ANALYZED THE CORRELATION OF CMV SEROPOSITIVITY WITH THE EPIGENETIC AGE IN THE VITALITY 90+COHORT 1920 (122 NONAGENARIANS AND 21 YOUNG CONTROLS, CMV SEROPOSITIVITY RATES 95% AND 57%, RESPECTIVELY). THE DATA SHOWED THAT CMV SEROPOSITIVITY WAS ASSOCIATED WITH A HIGHER EPIGENETIC AGE IN BOTH OF THESE AGE GROUPS (MEDIAN 26.5 VS. 24.0 (P < 0.02,MANN-WHITNEY U-TEST) IN THE YOUNG CONTROLS AND 76.0 VS. 70.0 (P < 0.01) IN THE NONAGENARIANS). THUS, THESE DATA PROVIDE A NEW ASPECT TO THE CMV ASSOCIATED PATHOLOGICAL PROCESSES.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
7  5081  33 PI3KDELTA COORDINATES TRANSCRIPTIONAL, CHROMATIN, AND METABOLIC CHANGES TO PROMOTE EFFECTOR CD8(+) T CELLS AT THE EXPENSE OF CENTRAL MEMORY. PATIENTS WITH ACTIVATED PHOSPHATIDYLINOSITOL 3-KINASE DELTA (PI3KDELTA) SYNDROME (APDS) PRESENT WITH SINOPULMONARY INFECTIONS, LYMPHADENOPATHY, AND CYTOMEGALVIRUS (CMV) AND/OR EPSTEIN-BARR VIRUS (EBV) VIREMIA, YET WHY PATIENTS FAIL TO CLEAR CERTAIN CHRONIC VIRAL INFECTIONS REMAINS INCOMPLETELY UNDERSTOOD. USING PATIENT SAMPLES AND A MOUSE MODEL (PIK3CD(E1020K/+) MICE), WE DEMONSTRATE THAT, UPON ACTIVATION, PIK3CD(E1020K/+) CD8(+) T CELLS EXHIBIT EXAGGERATED FEATURES OF EFFECTOR POPULATIONS BOTH IN VITRO AND AFTER VIRAL INFECTION THAT ARE ASSOCIATED WITH INCREASED FAS-MEDIATED APOPTOSIS DUE TO SUSTAINED FOXO1 PHOSPHORYLATION AND FASL DEREPRESSION, ENHANCED MTORC1 AND C-MYC SIGNATURES, METABOLIC PERTURBATIONS, AND AN ALTERED CHROMATIN LANDSCAPE. CONVERSELY, PIK3CD(E1020K/+) CD8(+) CELLS FAIL TO SUSTAIN EXPRESSION OF PROTEINS CRITICAL FOR CENTRAL MEMORY, INCLUDING TCF1. STRIKINGLY, ACTIVATED PIK3CD(E1020K/+) CD8(+) CELLS EXHIBIT ALTERED TRANSCRIPTIONAL AND EPIGENETIC CIRCUITS CHARACTERIZED BY PRONOUNCED INTERLEUKIN-2 (IL-2)/STAT5 SIGNATURES AND HEIGHTENED IL-2 RESPONSES THAT PREVENT DIFFERENTIATION TO MEMORY-LIKE CELLS IN IL-15. OUR DATA POSITION PI3KDELTA AS INTEGRATING MULTIPLE SIGNALING NODES THAT PROMOTE CD8(+) T CELL EFFECTOR DIFFERENTIATION, PROVIDING INSIGHT INTO PHENOTYPES OF PATIENTS WITH APDS.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
8  2421  37 EPIGENETIC SIGNATURE OF PD-1+ TCF1+ CD8 T CELLS THAT ACT AS RESOURCE CELLS DURING CHRONIC VIRAL INFECTION AND RESPOND TO PD-1 BLOCKADE. WE HAVE RECENTLY DEFINED A NOVEL POPULATION OF PD-1 (PROGRAMMED CELL DEATH 1)+ TCF1 (T CELL FACTOR 1)+ VIRUS-SPECIFIC CD8 T CELLS THAT FUNCTION AS RESOURCE CELLS DURING CHRONIC LCMV INFECTION AND PROVIDE THE PROLIFERATIVE BURST SEEN AFTER PD-1 BLOCKADE. SUCH CD8 T CELLS HAVE BEEN FOUND IN OTHER CHRONIC INFECTIONS AND ALSO IN CANCER IN MICE AND HUMANS. THESE CD8 T CELLS EXHIBIT STEM-LIKE PROPERTIES UNDERGOING SELF-RENEWAL AND ALSO DIFFERENTIATING INTO THE TERMINALLY EXHAUSTED CD8 T CELLS. HERE WE COMPARED THE EPIGENETIC SIGNATURE OF STEM-LIKE CD8 T CELLS WITH EXHAUSTED CD8 T CELLS. ATAC-SEQ ANALYSIS SHOWED THAT STEM-LIKE CD8 T CELLS HAD A UNIQUE SIGNATURE IMPLICATING ACTIVITY OF HMG (TCF) AND RHD (NF-KAPPAB) TRANSCRIPTION FACTOR FAMILY MEMBERS IN CONTRAST TO HIGHER ACCESSIBILITY TO ETS AND RUNX MOTIFS IN EXHAUSTED CD8 T CELLS. IN ADDITION, REGULATORY REGIONS OF THE TRANSCRIPTION FACTORS TCF7 AND ID3 WERE MORE ACCESSIBLE IN STEM-LIKE CELLS WHEREAS PRDM1 AND ID2 WERE MORE ACCESSIBLE IN EXHAUSTED CD8 T CELLS. WE ALSO COMPARED THE EPIGENETIC SIGNATURES OF THE 2 CD8 T CELL SUBSETS FROM CHRONICALLY INFECTED MICE WITH EFFECTOR AND MEMORY CD8 T CELLS GENERATED AFTER AN ACUTE LCMV INFECTION. BOTH CD8 T CELL SUBSETS GENERATED DURING CHRONIC INFECTION WERE STRIKINGLY DIFFERENT FROM CD8 T CELL SUBSETS FROM ACUTE INFECTION. INTERESTINGLY, THE STEM-LIKE CD8 T CELL SUBSET FROM CHRONIC INFECTION, DESPITE SHARING KEY FUNCTIONAL PROPERTIES WITH MEMORY CD8 T CELLS, HAD A VERY DISTINCT EPIGENETIC PROGRAM. THESE RESULTS SHOW THAT THE CHRONIC STEM-LIKE CD8 T CELL PROGRAM REPRESENTS A SPECIFIC ADAPTATION OF THE T CELL RESPONSE TO PERSISTENT ANTIGENIC STIMULATION.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
9  2268  34 EPIGENETIC PROGRAMMING OF T CELLS IMPACTS IMMUNE RECONSTITUTION IN HEMATOPOIETIC STEM CELL TRANSPLANT RECIPIENTS. IMMUNE RECONSTITUTION FOLLOWING HEMATOPOIETIC STEM CELL TRANSPLANTATION (HSCT) IS CRITICAL IN PREVENTING HARMFUL SEQUELAE IN RECIPIENTS WITH CYTOMEGALOVIRUS (CMV) INFECTION. TO UNDERSTAND THE MOLECULAR MECHANISMS UNDERLYING IMMUNE RECONSTITUTION KINETICS, WE PROFILED THE TRANSCRIPTOME-CHROMATIN ACCESSIBILITY LANDSCAPE OF CMV-SPECIFIC CD8(+) T CELLS FROM HCST RECIPIENTS WITH DIFFERENT IMMUNE RECONSTITUTION EFFICIENCIES. CMV-SPECIFIC T CELLS FROM HSCT RECIPIENTS WITH STABLE ANTIVIRAL IMMUNITY EXPRESSED HIGHER LEVELS OF INTERFERON/DEFENSE RESPONSE AND CELL CYCLE GENES IN AN INTERCONNECTED NETWORK INVOLVING PI3KCG, STAT5B, NFAT, RBPJ, AND LOWER HDAC6, INCREASING CHROMATIN ACCESSIBILITY AT THE ENHANCER REGIONS OF IMMUNE AND T-CELL RECEPTOR SIGNALING PATHWAY GENES. BY CONTRAST, THE TRANSCRIPTIONAL AND EPIGENOMIC SIGNATURES OF CMV-SPECIFIC T CELLS FROM HSCT RECIPIENTS WITH UNSTABLE IMMUNE RECONSTITUTION SHOWED COMMONALITIES WITH T-CELL RESPONSES IN OTHER NONRESOLVING CHRONIC INFECTIONS. THESE SIGNATURES INCLUDED HIGHER LEVELS OF EGR AND KLF FACTORS THAT, ALONG WITH LOWER JARID2 EXPRESSION, MAINTAINED HIGHER ACCESSIBILITY AT PROMOTER AND CPG-RICH REGIONS OF GENES ASSOCIATED WITH APOPTOSIS. FURTHERMORE, EPIGENETIC TARGETING VIA INHIBITION OF HDAC6 OR JARID2 ENHANCED THE TRANSCRIPTION OF GENES ASSOCIATED WITH DIFFERENTIAL RESPONSES, SUGGESTING THAT DRUGS TARGETING EPIGENOMIC MODIFIERS MAY HAVE THERAPEUTIC POTENTIAL FOR ENHANCING IMMUNE RECONSTITUTION IN HSCT RECIPIENTS. TAKEN TOGETHER, THESE ANALYSES DEMONSTRATE THAT TRANSCRIPTION FACTORS AND CHROMATIN MODULATORS CREATE DIFFERENT CHROMATIN ACCESSIBILITY LANDSCAPES IN T CELLS OF HSCT RECIPIENTS THAT NOT ONLY AFFECT IMMEDIATE GENE EXPRESSION BUT ALSO DIFFERENTIALLY PRIME CELLS FOR RESPONSES TO ADDITIONAL SIGNALS. EPIGENETIC THERAPY MAY BE A PROMISING STRATEGY TO PROMOTE IMMUNE RECONSTITUTION IN HSCT RECIPIENTS.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
10  1262  27 CUTTING EDGE: PROLONGED EXPOSURE TO HIV REINFORCES A POISED EPIGENETIC PROGRAM FOR PD-1 EXPRESSION IN VIRUS-SPECIFIC CD8 T CELLS. AG-SPECIFIC CD8 T CELLS PLAY A CRITICAL ROLE IN CONTROLLING HIV INFECTION BUT EVENTUALLY LOSE ANTIVIRAL FUNCTIONS IN PART BECAUSE OF EXPRESSION AND SIGNALING THROUGH THE INHIBITORY PROGRAMMED DEATH-1 (PD-1) RECEPTOR. TO BETTER UNDERSTAND THE IMPACT OF PROLONGED TCR LIGATION ON REGULATION OF PD-1 EXPRESSION IN HIV-SPECIFIC CD8 T CELLS, WE INVESTIGATED THE CAPACITY OF VIRUS-SPECIFIC CD8 T CELLS TO MODIFY THE PD-1 EPIGENETIC PROGRAM AFTER REDUCTION IN VIRAL LOAD. WE OBSERVED THAT THE TRANSCRIPTIONAL REGULATORY REGION WAS UNMETHYLATED IN THE PD-1(HI) HIV-SPECIFIC CD8 T CELLS, WHEREAS IT REMAINED METHYLATED IN DONOR-MATCHED NAIVE CELLS AT ACUTE AND CHRONIC STAGES OF INFECTION. SURPRISINGLY, THE PD-1 PROMOTER REMAINED UNMETHYLATED IN HIV-SPECIFIC CD8 T CELLS FROM SUBJECTS WITH A VIRAL LOAD CONTROLLED BY ANTIVIRAL THERAPY FOR >2 Y OR FROM ELITE CONTROLLERS. TOGETHER, THESE DATA DEMONSTRATE THAT THE EPIGENETIC PROGRAM AT THE PD-1 LOCUS BECOMES FIXED AFTER PROLONGED EXPOSURE TO HIV VIRUS.	2013	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
11  2270  27 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
12  2392  30 EPIGENETIC REPRESSION OF INTERLEUKIN 2 EXPRESSION IN SENESCENT CD4+ T CELLS DURING CHRONIC HIV TYPE 1 INFECTION. THE MOLECULAR MECHANISMS FOR IL2 GENE-SPECIFIC DYSREGULATION DURING CHRONIC HUMAN IMMUNODEFICIENCY VIRUS TYPE 1 (HIV-1) INFECTION ARE UNKNOWN. HERE, WE INVESTIGATED THE ROLE OF DNA METHYLATION IN SUPPRESSING INTERLEUKIN 2 (IL-2) EXPRESSION IN MEMORY CD4(+) T CELLS DURING CHRONIC HIV-1 INFECTION. WE OBSERVED THAT CPG SITES IN THE IL2 PROMOTER OF CD4(+) T CELLS WERE FULLY METHYLATED IN NAIVE CD4(+) T CELLS AND SIGNIFICANTLY DEMETHYLATED IN THE MEMORY POPULATIONS. INTERESTINGLY, WE FOUND THAT THE MEMORY CELLS THAT HAD A TERMINALLY DIFFERENTIATED PHENOTYPE AND EXPRESSED CD57 HAD INCREASED IL2 PROMOTER METHYLATION RELATIVE TO LESS DIFFERENTIATED MEMORY CELLS IN HEALTHY INDIVIDUALS. IMPORTANTLY, EARLY EFFECTOR MEMORY SUBSETS FROM HIV-1-INFECTED SUBJECTS EXPRESSED HIGH LEVELS OF CD57 AND WERE HIGHLY METHYLATED AT THE IL2 LOCUS. FURTHERMORE, THE INCREASED CD57 EXPRESSION ON MEMORY CD4(+) T CELLS WAS INVERSELY CORRELATED WITH IL-2 PRODUCTION. THESE DATA SUGGEST THAT DNA METHYLATION AT THE IL2 LOCUS IN CD4(+) T CELLS IS COUPLED TO IMMUNOSENESCENCE AND PLAYS A CRITICAL ROLE IN THE BROAD DYSFUNCTION THAT OCCURS IN POLYCLONAL T CELLS DURING HIV-1 INFECTION.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
13  1007  28 CHRONIC VIRUS INFECTION ENFORCES DEMETHYLATION OF THE LOCUS THAT ENCODES PD-1 IN ANTIGEN-SPECIFIC CD8(+) T CELLS. FUNCTIONALLY EXHAUSTED T CELLS HAVE HIGH EXPRESSION OF THE PD-1 INHIBITORY RECEPTOR, AND THERAPIES THAT BLOCK PD-1 SIGNALING SHOW PROMISE FOR RESOLVING CHRONIC VIRAL INFECTIONS AND CANCER. BY USING HUMAN AND MURINE SYSTEMS OF ACUTE AND CHRONIC VIRAL INFECTIONS, WE ANALYZED EPIGENETIC REGULATION OF PD-1 EXPRESSION DURING CD8(+) T CELL DIFFERENTIATION. DURING ACUTE INFECTION, NAIVE TO EFFECTOR CD8(+) T CELL DIFFERENTIATION WAS ACCOMPANIED BY A TRANSIENT LOSS OF DNA METHYLATION OF THE PDCD1 LOCUS THAT WAS DIRECTLY COUPLED TO THE DURATION AND STRENGTH OF T CELL RECEPTOR SIGNALING. FURTHER DIFFERENTIATION INTO FUNCTIONAL MEMORY CELLS COINCIDED WITH PDCD1 REMETHYLATION, PROVIDING AN ADAPTED PROGRAM FOR REGULATION OF PD-1 EXPRESSION. IN CONTRAST, THE PDCD1 REGULATORY REGION WAS COMPLETELY DEMETHYLATED IN EXHAUSTED CD8(+) T CELLS AND REMAINED UNMETHYLATED EVEN WHEN VIRUS TITERS DECREASED. THIS LACK OF DNA REMETHYLATION LEAVES THE PDCD1 LOCUS POISED FOR RAPID EXPRESSION, POTENTIALLY PROVIDING A SIGNAL FOR PREMATURE TERMINATION OF ANTIVIRAL FUNCTIONS.	2011	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
14  3373  30 HISTONE MODULATION BLOCKS TREG-INDUCED FOXP3 BINDING TO THE IL-2 PROMOTER OF VIRUS-SPECIFIC CD8(+) T CELLS FROM FELINE IMMUNODEFICIENCY VIRUS-INFECTED CATS. CD8(+) T CELLS ARE CRITICAL FOR CONTROLLING HIV INFECTION. DURING THE CHRONIC PHASE OF LENTIVIRAL INFECTION, CD8(+) T CELLS LOSE THEIR PROLIFERATIVE CAPACITY AND EXHIBIT IMPAIRED ANTIVIRAL FUNCTION. THIS LOSS OF CD8(+) T CELL FUNCTION IS DUE, IN PART, TO CD4(+)CD25(+) T REGULATORY (TREG) CELL-MEDIATED SUPPRESSION. OUR RESEARCH GROUP HAS DEMONSTRATED THAT LENTIVIRUS-ACTIVATED CD4(+)CD25(+) TREG CELLS INDUCE THE REPRESSIVE TRANSCRIPTION FACTOR FORKHEAD BOX P3 (FOXP3) IN AUTOLOGOUS CD8(+) T CELLS FOLLOWING CO-CULTURE. WE HAVE RECENTLY REPORTED THAT TREG-INDUCED FOXP3 BINDS THE INTERLEUKIN-2 (IL-2), INTERFERON-GAMMA (IFN- GAMMA), AND TUMOR NECROSIS FACTOR-ALPHA (TNF-ALPHA) PROMOTERS IN VIRUS-SPECIFIC CD8(+) T CELLS. THESE DATA SUGGEST AN IMPORTANT ROLE OF FOXP3-MEDIATED CD8(+) T CELL DYSFUNCTION IN LENTIVIRAL INFECTION. TO ELUCIDATE THE MECHANISM OF THIS SUPPRESSION, WE PREVIOUSLY REPORTED THAT DECREASED METHYLATION FACILITATES FOXP3 BINDING IN MITOGEN-ACTIVATED CD8(+) T CELLS FROM FELINE IMMUNODEFICIENCY VIRUS (FIV)-INFECTED CATS. WE DEMONSTRATED THE REDUCED BINDING OF FOXP3 TO THE IL-2 PROMOTER BY INCREASING METHYLATION OF CD8(+) T CELLS. IN THE STUDIES PRESENTED HERE, WE ASK IF ANOTHER FORM OF EPIGENETIC MODULATION MIGHT ALLEVIATE FOXP3-MEDIATED SUPPRESSION IN CD8(+) T CELLS. WE HYPOTHESIZED THAT DECREASING HISTONE ACETYLATION IN VIRUS-SPECIFIC CD8(+) T CELLS WOULD DECREASE TREG-INDUCED FOXP3 BINDING TO THE IL-2 PROMOTER. INDEED, USING ANACARDIC ACID (AA), A KNOWN HISTONE ACETYL TRANSFERASE (HAT) INHIBITOR, WE DEMONSTRATE A REDUCTION IN FOXP3 BINDING TO THE IL-2 PROMOTER IN VIRUS-SPECIFIC CD8(+) T CELLS CO-CULTURED WITH AUTOLOGOUS TREG CELLS. THESE DATA IDENTIFY A NOVEL MECHANISM OF FOXP3-MEDIATED CD8(+) T CELL DYSFUNCTION DURING LENTIVIRAL INFECTION.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
15  5704  28 SINGLE-CELL RNA-SEQ REVEALS TOX AS A KEY REGULATOR OF CD8(+) T CELL PERSISTENCE IN CHRONIC INFECTION. PROGENITOR-LIKE CD8(+) T CELLS MEDIATE LONG-TERM IMMUNITY TO CHRONIC INFECTION AND CANCER AND RESPOND POTENTLY TO IMMUNE CHECKPOINT BLOCKADE. THESE CELLS SHARE TRANSCRIPTIONAL REGULATORS WITH MEMORY PRECURSOR CELLS, INCLUDING T CELL-SPECIFIC TRANSCRIPTION FACTOR 1 (TCF1), BUT IT IS UNCLEAR WHETHER THEY ADOPT DISTINCT PROGRAMS TO ADAPT TO THE IMMUNOSUPPRESSIVE ENVIRONMENT. BY COMPARING THE SINGLE-CELL TRANSCRIPTOMES AND EPIGENETIC PROFILES OF CD8(+) T CELLS RESPONDING TO ACUTE AND CHRONIC VIRAL INFECTIONS, WE FOUND THAT PROGENITOR-LIKE CD8(+) T CELLS BECAME DISTINCT FROM MEMORY PRECURSOR CELLS BEFORE THE PEAK OF THE T CELL RESPONSE. WE DISCOVERED A COEXPRESSION GENE MODULE CONTAINING TOX THAT EXHIBITED HIGHER TRANSCRIPTIONAL ACTIVITY ASSOCIATED WITH MORE ABUNDANT ACTIVE HISTONE MARKS IN PROGENITOR-LIKE CELLS THAN MEMORY PRECURSOR CELLS. MOREOVER, THYMOCYTE SELECTION-ASSOCIATED HIGH MOBILITY GROUP BOX PROTEIN TOX (TOX) PROMOTED THE PERSISTENCE OF ANTIVIRAL CD8(+) T CELLS AND WAS REQUIRED FOR THE PROGRAMMING OF PROGENITOR-LIKE CD8(+) T CELLS. THUS, LONG-TERM CD8(+) T CELL IMMUNITY TO CHRONIC VIRAL INFECTION REQUIRES UNIQUE TRANSCRIPTIONAL AND EPIGENETIC PROGRAMS ASSOCIATED WITH THE TRANSCRIPTION FACTOR TOX.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
16  6044  33 THE COMPLEX BIOLOGY OF HUMAN CYTOMEGALOVIRUS LATENCY. WHILE MANY VIRAL INFECTIONS ARE LIMITED AND EVENTUALLY RESOLVED BY THE HOST IMMUNE RESPONSE OR BY DEATH OF THE HOST, OTHER VIRUSES ESTABLISH LONG-TERM RELATIONSHIPS WITH THE HOST BY WAY OF A PERSISTENT INFECTION, THAT RANGE FROM CHRONIC VIRUSES THAT MAY BE EVENTUALLY CLEARED TO THOSE THAT ESTABLISH LIFE-LONG PERSISTENT OR LATENT INFECTION. VIRUSES INFECTING HOSTS FROM BACTERIA TO HUMANS ESTABLISH QUIESCENT INFECTIONS THAT MUST BE REACTIVATED TO PRODUCE PROGENY. FOR MAMMALIAN VIRUSES, MOST NOTABLY HERPESVIRUSES, THIS QUIESCENT MAINTENANCE OF VIRAL GENOMES IN THE ABSENCE OF VIRUS REPLICATION IS REFERRED TO AS LATENCY. THE LATENT STRATEGY ALLOWS THE VIRUS TO PERSIST QUIESCENTLY WITHIN A SINGLE HOST UNTIL CONDITIONS INDICATE A NEED TO REACTIVATE TO REACH A NEW HOST OR, TO RE-SEED A RESERVOIR WITHIN THE HOST. HERE, I REVIEW COMMON THEMES IN VIRAL STRATEGIES TO REGULATE THE LATENT CYCLE AND REACTIVATE FROM IT RANGING FROM BACTERIOPHAGE TO HERPESVIRUSES WITH A FOCUS ON HUMAN CYTOMEGALOVIRUS (HCMV). THEMES CENTRAL TO HERPESVIRUS LATENCY INCLUDE, EPIGENETIC REPRESSION OF VIRAL GENE EXPRESSION AND MECHANISMS TO REGULATE HOST SIGNALING AND SURVIVAL. CRITICAL TO THE SUCCESS OF A LATENT PROGRAM ARE MECHANISMS BY WHICH THE VIRUS CAN "SENSE" FLUCTUATIONS IN HOST BIOLOGY (WITHIN THE HOST) OR ENVIRONMENT (OUTSIDE THE HOST) AND MAKE APPROPRIATE "DECISIONS" TO MAINTAIN LATENCY OR RE-INITIATE THE REPLICATIVE PROGRAM. THE SIGNALS OR ENVIRONMENTS THAT INDICATE THE ESTABLISHMENT OF A LATENT STATE, THE VERY NATURE OF THE LATENT STATE, AS WELL AS THE SIGNALS DRIVING REACTIVATION HAVE BEEN TOPICS OF INTENSE STUDY FROM BACTERIOPHAGE TO HUMAN VIRUSES, AS THESE QUESTIONS ENCOMPASS THE HEIGHT OF COMPLEXITY IN VIRUS-HOST INTERACTIONS-WHERE THE HOST AND THE VIRUS COEXIST.	2022	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
17  1319  33 DEMETHYLATION OF THE PD-1 PROMOTER IS IMPRINTED DURING THE EFFECTOR PHASE OF CD8 T CELL EXHAUSTION. PD-1 IS AN INHIBITORY RECEPTOR THAT HAS A MAJOR ROLE IN T CELL DYSFUNCTION DURING CHRONIC INFECTIONS AND CANCER. WHILE DEMETHYLATION OF THE PD-1 PROMOTER DNA IS OBSERVED IN EXHAUSTED T CELLS ISOLATED FROM CHRONICALLY INFECTED INDIVIDUALS, LITTLE IS KNOWN ABOUT WHEN THIS STABLE DEMETHYLATION OF PD-1 PROMOTER DNA IS PROGRAMMED DURING THE COURSE OF A CHRONIC INFECTION. TO ASSESS IF PD-1 PROMOTER DNA DEMETHYLATION IS IMPACTED BY PROLONGED STIMULATION DURING EFFECTOR PHASE OF CHRONIC INFECTION, WE ADOPTIVELY TRANSFERRED VIRUS-SPECIFIC DAY 8 EFFECTOR CD8 T CELLS FROM MICE INFECTED WITH LYMPHOCYTIC CHORIOMENINGITIS VIRUS (LCMV) CLONE 13 INTO RECIPIENT MICE THAT HAD CLEARED AN ACUTE INFECTION. WE OBSERVED THAT LCMV-SPECIFIC CD8 T CELLS FROM CHRONICALLY INFECTED MICE MAINTAINED THEIR SURFACE EXPRESSION OF PD-1 EVEN AFTER TRANSFER INTO ACUTE IMMUNE MICE UNTIL DAY 45 POSTTRANSFER. INTERESTINGLY, THE PD-1 TRANSCRIPTIONAL REGULATORY REGION CONTINUED TO REMAIN UNMETHYLATED IN THESE DONOR CD8 T CELLS GENERATED FROM A CHRONIC INFECTION. THE OBSERVED MAINTENANCE OF PD-1 SURFACE EXPRESSION AND THE DEMETHYLATED PD-1 PROMOTER WERE NOT A RESULT OF RESIDUAL ANTIGEN IN THE RECIPIENT MICE, BECAUSE SIMILAR RESULTS WERE SEEN WHEN CHRONIC INFECTION-INDUCED EFFECTOR CELLS WERE TRANSFERRED INTO MICE INFECTED WITH A VARIANT STRAIN OF LCMV (LCMV V35A) BEARING A MUTATION IN THE COGNATE MAJOR HISTOCOMPATIBILITY COMPLEX CLASS I (MHC-I) EPITOPE THAT IS RECOGNIZED BY THE DONOR CD8 T CELLS. IMPORTANTLY, THE MAINTENANCE OF PD-1 PROMOTER DEMETHYLATION IN MEMORY CD8 T CELLS WAS COUPLED WITH IMPAIRED CLONAL EXPANSION AND HIGHER PD-1 RE-EXPRESSION UPON SECONDARY CHALLENGE. THESE DATA SHOW THAT THE IMPRINTING OF THE EPIGENETIC PROGRAM OF THE INHIBITORY RECEPTOR PD-1 OCCURS DURING THE EFFECTOR PHASE OF CHRONIC VIRAL INFECTION. IMPORTANCE: SINCE PD-1 IS A MAJOR INHIBITORY RECEPTOR REGULATING T CELL DYSFUNCTION DURING CHRONIC VIRAL INFECTION AND CANCERS, A BETTER UNDERSTANDING OF THE MECHANISMS THAT REGULATE PD-1 EXPRESSION IS IMPORTANT. IN THIS WORK, WE DEMONSTRATE THAT THE PD-1 EPIGENETIC PROGRAM IN ANTIGEN-SPECIFIC CD8 T CELLS IS FIXED DURING THE PRIMING PHASE OF CHRONIC INFECTION.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                           
18  2242  29 EPIGENETIC MODULATION OF CD8(+) T CELL FUNCTION IN LENTIVIRUS INFECTIONS: A REVIEW. CD8(+) T CELLS ARE CRITICAL FOR CONTROLLING VIREMIA DURING HUMAN IMMUNODEFICIENCY VIRUS (HIV) INFECTION. THESE CELLS PRODUCE CYTOLYTIC FACTORS AND ANTIVIRAL CYTOKINES THAT ELIMINATE VIRALLY- INFECTED CELLS. DURING THE CHRONIC PHASE OF HIV INFECTION, CD8(+) T CELLS PROGRESSIVELY LOSE THEIR PROLIFERATIVE CAPACITY AND ANTIVIRAL FUNCTIONS. THESE DYSFUNCTIONAL CELLS ARE UNABLE TO CLEAR THE PRODUCTIVELY INFECTED AND REACTIVATED CELLS, REPRESENTING A ROADBLOCK IN HIV CURE. THEREFORE, MECHANISMS TO UNDERSTAND CD8(+) T CELL DYSFUNCTION AND STRATEGIES TO BOOST CD8(+) T CELL FUNCTION NEED TO BE INVESTIGATED. USING THE FELINE IMMUNODEFICIENCY VIRUS (FIV) MODEL FOR LENTIVIRAL PERSISTENCE, WE HAVE DEMONSTRATED THAT CD8(+) T CELLS EXHIBIT EPIGENETIC CHANGES SUCH AS DNA DEMETHYLATION DURING THE COURSE OF INFECTION AS COMPARED TO UNINFECTED CATS. WE HAVE ALSO DEMONSTRATED THAT LENTIVIRUS-ACTIVATED CD4(+)CD25(+) T REGULATORY CELLS INDUCE FORKHEAD BOX P3 (FOXP3) EXPRESSION IN VIRUS-SPECIFIC CD8(+) T CELL TARGETS, WHICH BINDS THE INTERLEUKIN (IL)-2, TUMOR NECROSIS FACTOR (TNF)-&ALPHA;, AND INTERFERON (IFN)-&GAMMA; PROMOTERS IN THESE CD8(+) T CELLS. FINALLY, WE HAVE REPORTED THAT EPIGENETIC MODULATION REDUCES FOXP3 BINDING TO THESE PROMOTER REGIONS. THIS REVIEW COMPARES AND CONTRASTS OUR CURRENT UNDERSTANDING OF CD8(+) T CELL EPIGENETICS AND MECHANISMS OF LYMPHOCYTE SUPPRESSION DURING THE COURSE OF LENTIVIRAL INFECTION FOR TWO ANIMAL MODELS, FIV AND SIMIAN IMMUNODEFICIENCY VIRUS (SIV).	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
19   559  27 BACH2 ENFORCES THE TRANSCRIPTIONAL AND EPIGENETIC PROGRAMS OF STEM-LIKE CD8(+) T CELLS. DURING CHRONIC INFECTION AND CANCER, A SELF-RENEWING CD8(+) T CELL SUBSET MAINTAINS LONG-TERM IMMUNITY AND IS CRITICAL TO THE EFFECTIVENESS OF IMMUNOTHERAPY. THESE STEM-LIKE CD8(+) T CELLS DIVERGE FROM OTHER CD8(+) SUBSETS EARLY AFTER CHRONIC VIRAL INFECTION. HOWEVER, PATHWAYS GUARDING STEM-LIKE CD8(+) T CELLS AGAINST TERMINAL EXHAUSTION REMAIN UNCLEAR. HERE, WE SHOW THAT THE GENE ENCODING TRANSCRIPTIONAL REPRESSOR BACH2 IS TRANSCRIPTIONALLY AND EPIGENETICALLY ACTIVE IN STEM-LIKE CD8(+) T CELLS BUT NOT TERMINALLY EXHAUSTED CELLS EARLY AFTER INFECTION. BACH2 OVEREXPRESSION ENFORCED STEM-LIKE CELL FATE, WHEREAS BACH2 DEFICIENCY IMPAIRED STEM-LIKE CD8(+) T CELL DIFFERENTIATION. SINGLE-CELL TRANSCRIPTOMIC AND EPIGENOMIC APPROACHES REVEALED THAT BACH2 ESTABLISHED THE TRANSCRIPTIONAL AND EPIGENETIC PROGRAMS OF STEM-LIKE CD8(+) T CELLS. IN ADDITION, BACH2 SUPPRESSED THE MOLECULAR PROGRAM DRIVING TERMINAL EXHAUSTION THROUGH TRANSCRIPTIONAL REPRESSION AND EPIGENETIC SILENCING. THUS, OUR STUDY REVEALS A NEW PATHWAY THAT ENFORCES COMMITMENT TO STEM-LIKE CD8(+) LINEAGE AND PREVENTS AN ALTERNATIVE TERMINALLY EXHAUSTED CELL FATE.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
20  5015  33 PERSISTENCE OF SELF-REACTIVE CD8+ T CELLS IN THE CNS REQUIRES TOX-DEPENDENT CHROMATIN REMODELING. SELF-REACTIVE CD8(+) T CELLS ARE IMPORTANT MEDIATORS OF PROGRESSIVE TISSUE DAMAGE IN AUTOIMMUNE DISEASES, BUT THE MOLECULAR PROGRAM UNDERLYING THESE CELLS' FUNCTIONAL ADAPTATION IS UNCLEAR. HERE WE CHARACTERIZE THE TRANSCRIPTIONAL AND EPIGENETIC LANDSCAPE OF SELF-REACTIVE CD8(+) T CELLS IN A MOUSE MODEL OF PROTRACTED CENTRAL NERVOUS SYSTEM (CNS) AUTOIMMUNITY AND COMPARE IT TO POPULATIONS OF CNS-RESIDENT MEMORY CD8(+) T CELLS EMERGING FROM ACUTE VIRAL INFECTION. WE FIND THAT AUTOIMMUNE CD8(+) T CELLS PERSISTING AT SITES OF SELF-ANTIGEN EXHIBIT CHARACTERISTIC TRANSCRIPTIONAL REGULATION TOGETHER WITH DISTINCT EPIGENETIC REMODELING. THIS SELF-REACTIVE CD8(+) T CELL FATE DEPENDS ON THE TRANSCRIPTIONAL REGULATION BY THE DNA-BINDING HMG-BOX PROTEIN TOX WHICH REMODELS MORE THAN 400 GENOMIC REGIONS INCLUDING LOCI SUCH AS TCF7, WHICH IS CENTRAL TO STEMNESS OF CD8(+) T CELLS. CONTINUOUS EXPOSURE TO CNS SELF-ANTIGEN SUSTAINS TOX LEVELS IN SELF-REACTIVE CD8(+) T CELLS, WHEREAS GENETIC ABLATION OF TOX IN CD8(+) T CELLS RESULTS IN SHORTENED PERSISTENCE OF SELF-REACTIVE CD8(+) T CELLS IN THE INFLAMED CNS. OUR STUDY ESTABLISHES AND CHARACTERIZES THE GENETIC DIFFERENTIATION PROGRAM ENABLING CHRONIC T CELL-DRIVEN IMMUNOPATHOLOGY IN CNS AUTOIMMUNITY.	2021