1 5147 129 POTENTIAL ROLES OF LONG NONCODING RNAS AS THERAPEUTIC TARGETS IN ORGAN TRANSPLANTATION. ORGAN TRANSPLANTATION IS THE MOST PREFERRED TREATMENT OPTION FOR END-STAGE ORGAN DISEASES; HOWEVER, ALLOGRAFT REJECTION IS THE MAJOR HURDLE IN SUCCESSFUL LONG-TERM TRANSPLANT SURVIVAL. IN SPITE OF DEVELOPING BETTER HLA MATCHING AND MORE EFFECTIVE IMMUNOSUPPRESSIVE REGIMEN, ONE-YEAR GRAFT SURVIVAL HAS BEEN INCREASED BY NEARLY 90% AND THE INCIDENCE OF ACUTE REJECTION BY ONE-YEAR POST-TRANSPLANTATION HAS BEEN DECREASED BY 12.2% IN THE LAST DECADES, CHRONIC ALLOGRAFT REJECTION HAS REMAINED AS ONE OF THE MAJOR OBSTACLES TO THE LONG-LASTING SURVIVAL OF THE TRANSPLANTED ALLOGRAFT. THEREFORE, SEEMINGLY PREVENTING THE ALLOGRAFT REJECTION AND INDUCING IMMUNOLOGICAL TOLERANCE AGAINST TRANSPLANTED ALLOGRAFTS IS ONE OF THE PRIMARY GOALS IN TRANSPLANTATION RESEARCH TO ENABLE LONG-LASTING GRAFT SURVIVAL. VARIOUS MECHANISMS SUCH AS LONG NONCODING RNAS (LNCRNAS) HAVE BEEN PROPOSED THAT INDUCE IMMUNE TOLERANCE BY MODULATING THE GENE EXPRESSION AND REGULATING INNATE AND ADAPTIVE IMMUNE RESPONSES DURING TRANSPLANTATION. BESIDES, BECAUSE OF INVOLVEMENT IN REGULATING EPIGENETIC, TRANSCRIPTIONAL, AND POST-TRANSLATIONAL MECHANISMS, LNCRNAS COULD AFFECT ALLOGRAFT STATUS. THEREFORE, THESE MOLECULES COULD BE CONSIDERED AS THE POTENTIAL TARGETS FOR PREDICTION, PROGNOSIS, DIAGNOSIS, AND TREATMENT OF GRAFT REJECTION. IT IS SUGGESTED THAT THE NONINVASIVE PREDICTIVE BIOMARKERS HOLD PROMISE TO OVERCOME THE CURRENT LIMITATIONS OF CONVENTIONAL TISSUE BIOPSY IN THE DIAGNOSIS OF REJECTION. HENCE, THIS REVIEW AIMS TO PROVIDE A COMPREHENSIVE OVERVIEW OF LNCRNAS AND THEIR FUNCTION TO FACILITATE DIAGNOSIS, PROGNOSIS, AND PREDICTION OF THE RISK OF GRAFT REJECTION, AND THE SUGGESTIVE THERAPEUTIC CHOICES AFTER TRANSPLANTATION. 2022 2 5139 34 POTENTIAL NOVEL BIOMARKERS IN CHRONIC GRAFT-VERSUS-HOST DISEASE. PROGNOSTIC, DIAGNOSTIC OR PREDICTIVE BIOMARKERS ARE URGENTLY NEEDED FOR ASSESSMENT OF CHRONIC GRAFT-VERSUS-HOST DISEASE (CGVHD), A MAJOR RISK FOR PATIENTS UNDERGOING ALLOGENEIC HEMATOPOIETIC STEM CELL TRANSPLANTATION. THE MAIN GOAL OF THIS REVIEW GENERATED WITHIN THE COST ACTION EUROGRAFT "INTEGRATED EUROPEAN NETWORK ON CHRONIC GRAFT VERSUS HOST DISEASE" WAS TO IDENTIFY POTENTIAL NOVEL BIOMARKERS FOR CGVHD BESIDES THE WIDELY ACCEPTED MOLECULAR AND CELLULAR BIOMARKERS. THUS, THE FOCUS WAS ON CELLULAR BIOMARKERS, ALLOANTIBODIES, GLYCOMICS, ENDOTHELIAL DERIVED PARTICLES, EXTRACELLULAR VESICLES, MICROBIOME, EPIGENETIC AND NEUROLOGIC CHANGES IN CGVHD PATIENTS. BOTH HOST-REACTIVE ANTIBODIES IN GENERAL, AND PARTICULARLY ALLOANTIBODIES HAVE BEEN ASSOCIATED WITH CGVHD AND REQUIRE FURTHER CONSIDERATION. GLYCANS ATTACHED TO IGG MODULATE ITS ACTIVITY AND REPRESENT A PROMISING PREDICTIVE AND/OR STRATIFICATION BIOMARKER FOR CGVHD. FURTHERMORE, EPIGENETIC CHANGES SUCH AS MICRORNAS AND DNA METHYLATION REPRESENT POTENTIAL BIOMARKERS FOR MONITORING CGVHD PATIENTS AND NOVEL TARGETS FOR DEVELOPING NEW TREATMENT APPROACHES. FINALLY, THE MICROBIOME LIKELY AFFECTS THE PATHOPHYSIOLOGY OF CGVHD; BACTERIAL STRAINS AS WELL AS MICROBIAL METABOLITES COULD DISPLAY POTENTIAL BIOMARKERS FOR DYSBIOSIS AND RISK FOR THE DEVELOPMENT OF CGVHD. IN SUMMARY, ALTHOUGH THERE ARE NO VALIDATED BIOMARKERS CURRENTLY AVAILABLE FOR CLINICAL USE TO BETTER INFORM ON THE DIAGNOSIS, PROGNOSIS OR PREDICTION OF OUTCOME FOR CGVHD, MANY NOVEL SOURCES OF POTENTIAL MARKERS HAVE SHOWN PROMISE AND WARRANT FURTHER INVESTIGATION USING WELL CHARACTERIZED, MULTI-CENTER PATIENT COHORTS. 2020 3 4058 24 MARKERS OF REJECTION OF A LUNG ALLOGRAFT: STATE OF THE ART. CHRONIC LUNG ALLOGRAFT DYSFUNCTION (CLAD) AFFECTS APPROXIMATELY 50% OF ALL LUNG TRANSPLANT RECIPIENTS BY 5 POST-OPERATIVE YEARS AND IS THE LEADING CAUSE OF DEATH IN LUNG TRANSPLANT RECIPIENTS. EARLY CLAD DIAGNOSIS OR IDEALLY PREDICTION OF CLAD IS ESSENTIAL TO ENABLE EARLY INTERVENTION BEFORE SIGNIFICANT LUNG INJURY OCCURS. NEW TECHNOLOGIES HAVE EMERGED TO FACILITATE BIOMARKER DISCOVERY, INCLUDING EPIGENETIC MODIFICATION AND SINGLE-CELL RNA SEQUENCING. THIS REVIEW EXAMINES NEW AND EXISTING TECHNOLOGIES FOR BIOMARKER DISCOVERY AND THE CURRENT STATE OF RESEARCH ON BIOMARKERS FOR IDENTIFYING LUNG TRANSPLANT REJECTION. 2022 4 72 32 A MOLECULAR SIGNATURE FOR DELAYED GRAFT FUNCTION. CHRONIC KIDNEY DISEASE AND ASSOCIATED COMORBIDITIES (DIABETES, CARDIOVASCULAR DISEASES) MANIFEST WITH AN ACCELERATED AGEING PHENOTYPE, LEADING ULTIMATELY TO ORGAN FAILURE AND RENAL REPLACEMENT THERAPY. THIS PROCESS CAN BE MODULATED BY EPIGENETIC AND ENVIRONMENTAL FACTORS WHICH PROMOTE LOSS OF PHYSIOLOGICAL FUNCTION AND RESILIENCE TO STRESS EARLIER, LINKING BIOLOGICAL AGE WITH ADVERSE OUTCOMES POST-TRANSPLANTATION INCLUDING DELAYED GRAFT FUNCTION (DGF). THE MOLECULAR FEATURES UNDERPINNING THIS HAVE YET TO BE FULLY ELUCIDATED. WE HAVE DETERMINED A MOLECULAR SIGNATURE FOR LOSS OF RESILIENCE AND IMPAIRED PHYSIOLOGICAL FUNCTION, VIA A SYNCHRONOUS GENOME, TRANSCRIPTOME AND PROTEOME SNAPSHOT, USING HUMAN RENAL ALLOGRAFTS AS A SOURCE OF HEALTHY TISSUE AS AN IN VIVO MODEL OF AGEING IN HUMANS. THIS COMPRISES 42 SPECIFIC TRANSCRIPTS, RELATED THROUGH IFNGAMMA SIGNALLING, WHICH IN ALLOGRAFTS DISPLAYING CLINICALLY IMPAIRED PHYSIOLOGICAL FUNCTION (DGF) EXHIBITED A GREATER MAGNITUDE OF CHANGE IN TRANSCRIPTIONAL AMPLITUDE AND ELEVATED EXPRESSION OF NONCODING RNAS AND PSEUDOGENES, CONSISTENT WITH INCREASED ALLOSTATIC LOAD. THIS WAS ACCOMPANIED BY INCREASED DNA METHYLATION WITHIN THE PROMOTER AND INTRAGENIC REGIONS OF THE DGF PANEL IN PREPERFUSION ALLOGRAFTS WITH IMMEDIATE GRAFT FUNCTION. PATHWAY ANALYSIS INDICATED THAT AN INABILITY TO SUFFICIENTLY RESOLVE INFLAMMATORY RESPONSES WAS ENABLED BY DECREASED RESILIENCE TO STRESS AND RESULTED IN IMPAIRED PHYSIOLOGICAL FUNCTION IN BIOLOGICALLY OLDER ALLOGRAFTS. CROSS-COMPARISON WITH PUBLICALLY AVAILABLE DATA SETS FOR RENAL PATHOLOGIES IDENTIFIED SIGNIFICANT TRANSCRIPTIONAL COMMONALITY FOR OVER 20 DGF TRANSCRIPTS. OUR DATA ARE CLINICALLY RELEVANT AND IMPORTANT, AS THEY PROVIDE A CLEAR MOLECULAR SIGNATURE FOR THE BURDEN OF "WEAR AND TEAR" WITHIN THE KIDNEY AND THUS AGE-RELATED PHYSIOLOGICAL CAPABILITY AND RESILIENCE. 2018 5 4148 39 MECHANISTIC BASIS OF EX VIVO UMBILICAL CORD BLOOD STEM PROGENITOR CELL EXPANSION. UMBILICAL CORD BLOOD (CB) TRANSPLANTATION HAS BEEN USED SUCCESSFULLY IN HUMANS FOR THREE DECADES DUE TO ITS RAPID AVAILABILITY FOR PATIENTS LACKING A SUITABLE ALLOGENEIC DONOR, LESS STRINGENT HLA MATCHING REQUIREMENTS, AND LOW RATES OF RELAPSE AND CHRONIC GRAFT-VERSUS-HOST DISEASE (GVHD). HOWEVER, CB TRANSPLANTATION IS ASSOCIATED WITH COMPLICATIONS, SUCH AS DELAYED HEMATOPOIETIC ENGRAFTMENT, GRAFT FAILURE, WHICH INCREASES INFECTION AND BLEEDING AND CAUSES LONGER HOSPITAL STAYS, AND TRANSPLANT-RELATED MORTALITY. THE MAJORITY OF THESE BIOLOGICAL LIMITATIONS ARE DUE TO THE UNFORESEEABLE FUNCTIONAL POTENCY OF MULTIPOTENT HEMATOPOIETIC STEM CELLS (HSCS), WHICH REDUCE THE PREDICTABILITY OF SUCCESSFUL TRANSPLANTATION; HOWEVER, SEVERAL STRATEGIES HAVE BEEN DEVELOPED TO INCREASE THE NUMBER OF HEMATOPOIETIC STEM PROGENITOR CELLS (HSPCS) INFUSED DURING CB TRANSPLANTATION. THIS REVIEW PRIMARILY ADDRESSES THE METHODS THAT PROMOTE EX VIVO CB EXPANSION WITHIN THE CONTEXT OF SYMMETRICAL AND ASYMMETRICAL HSC DIVISION AND THOSE THAT RELY ON EPIGENETIC MECHANISMS, ALONG WITH THE REPORTEDLY MOST SUCCESSFUL CYTOKINE COMBINATIONS. WE ALSO REVIEW RECENT CLINICAL RESEARCH ON SMALL MOLECULES (STEMREGENIN-1, UM171, AND NICOTINAMIDE) IN EX VIVO EXPANDED CB AND DISCUSS YET UNVALIDATED PRECLINICAL STRATEGIES. EXPANDING AND TRANSPLANTING CB GRAFT ENRICHED IN HSPCS IN A SINGLE CB UNIT IS A PARTICULARLY EXCITING PROSPECT WITH THE POTENTIAL TO IMPROVE THE USE AND AVAILABILITY OF CB GRAFTS. GREATER KNOWLEDGE OF OPTIMAL EX VIVO EXPANSION STRATEGIES, CELL LONGEVITY, AND GRAFT POTENCY WILL EXPAND THE SCOPE OF CELLULAR THERAPIES. ALSO THE DEVELOPMENT OF ADEQUATE EX VIVO HSPC EXPANSION STRATEGIES COULD BRING EXPANDED CORD BLOOD GRAFTS TO THE FOREFRONT OF TRANSPLANT THERAPY AND REGENERATIVE MEDICINE. 2020 6 1307 32 DEFINING A METHYLATION SIGNATURE ASSOCIATED WITH OPERATIONAL TOLERANCE IN KIDNEY TRANSPLANT RECIPIENTS. OPERATIONAL TOLERANCE AFTER KIDNEY TRANSPLANTATION IS DEFINED AS STABLE GRAFT ACCEPTANCE WITHOUT THE NEED FOR IMMUNOSUPPRESSION THERAPY. HOWEVER, IT IS NOT CLEAR WHICH CELLULAR AND MOLECULAR PATHWAYS ARE DRIVING TOLERANCE IN THESE PATIENTS. WE PERFORMED GENOME-WIDE ANALYSIS OF DNA METHYLATION IN PERIPHERAL BLOOD MONONUCLEAR CELLS FROM KIDNEY TRANSPLANT RECIPIENTS WITH CHRONIC REJECTION AND OPERATIONAL TOLERANCE FROM THE GENETIC ANALYSIS OF MOLECULAR BIOMARKERS OF IMMUNOLOGICAL TOLERANCE (GAMBIT) STUDY. OUR RESULTS SHOWED THAT BOTH CLINICAL STAGES DIVERGE IN 2737 GENES, INDICATING THAT EACH ONE HAS A SPECIFIC METHYLATION SIGNATURE ASSOCIATED WITH TRANSPLANT OUTCOME. WE ALSO OBSERVED THAT TOLERANCE IS ASSOCIATED WITH DEMETHYLATION IN GENES INVOLVED IN IMMUNE FUNCTION, INCLUDING B AND T CELL ACTIVATION AND TH17 DIFFERENTIATION, WHILE IN CHRONIC REJECTION IT IS ASSOCIATED WITH INTRACELLULAR SIGNALING AND UBIQUITINATION PATHWAYS. USING CO-EXPRESSION NETWORK ANALYSIS, WE SELECTED 12 GENOMIC REGIONS THAT ARE SPECIFICALLY HYPOMETHYLATED OR HYPERMETHYLATED IN TOLERANT PATIENTS. ANALYSIS OF THESE GENES IN TRANSPLANTED PATIENTS WITH LOW DOSE OF STEROIDS SHOWED THAT THESE HAVE A SIMILAR METHYLATION SIGNATURE TO THAT OF TOLERANT RECIPIENTS. OVERALL, THESE RESULTS DEMONSTRATE THAT METHYLATION ANALYSIS CAN MIRROR THE IMMUNE STATUS ASSOCIATED WITH TRANSPLANT OUTCOME AND PROVIDES A STARTING POINT FOR UNDERSTANDING THE EPIGENETIC MECHANISMS ASSOCIATED WITH TOLERANCE. 2021 7 3856 33 ISCHAEMIA REPERFUSION INJURY: MECHANISMS OF PROGRESSION TO CHRONIC GRAFT DYSFUNCTION. THE INCREASING USE OF EXTENDED CRITERIA ORGANS TO MEET THE DEMAND FOR KIDNEY TRANSPLANTATION RAISES AN IMPORTANT QUESTION OF HOW THE SEVERITY OF EARLY ISCHAEMIC INJURY INFLUENCES LONG-TERM OUTCOMES. SIGNIFICANT ACUTE ISCHAEMIC KIDNEY INJURY IS ASSOCIATED WITH DELAYED GRAFT FUNCTION, INCREASED IMMUNE-ASSOCIATED EVENTS AND, ULTIMATELY, EARLIER DETERIORATION OF GRAFT FUNCTION. A COMPREHENSIVE UNDERSTANDING OF IMMEDIATE MOLECULAR EVENTS THAT ENSUE POST-ISCHAEMIA AND THEIR POTENTIAL LONG-TERM CONSEQUENCES ARE KEY TO THE DISCOVERY OF NOVEL THERAPEUTIC TARGETS. ACUTE ISCHAEMIC INJURY PRIMARILY AFFECTS TUBULAR STRUCTURE AND FUNCTION. DEPENDING ON THE SEVERITY AND PERSISTENCE OF THE INSULT, THIS MAY RESOLVE COMPLETELY, LEADING TO RESTORATION OF NORMAL FUNCTION, OR BE SUSTAINED, RESULTING IN PERSISTENT RENAL IMPAIRMENT AND PROGRESSIVE FUNCTIONAL LOSS. LONG-TERM EFFECTS OF ACUTE RENAL ISCHAEMIA ARE MEDIATED BY SEVERAL MECHANISMS INCLUDING HYPOXIA, HIF-1 ACTIVATION, ENDOTHELIAL DYSFUNCTION LEADING TO VASCULAR RAREFACTION, SUSTAINED PRO-INFLAMMATORY STIMULI INVOLVING INNATE AND ADAPTIVE IMMUNE RESPONSES, FAILURE OF TUBULAR CELLS TO RECOVER AND EPIGENETIC CHANGES. THIS REVIEW DESCRIBES THE BIOLOGICAL RELEVANCE AND INTERACTION OF THESE MECHANISMS BASED ON CURRENTLY AVAILABLE EVIDENCE. 2019 8 3670 35 INFLAMMAGING AND COMPLEMENT SYSTEM: A LINK BETWEEN ACUTE KIDNEY INJURY AND CHRONIC GRAFT DAMAGE. THE ABERRANT ACTIVATION OF COMPLEMENT SYSTEM IN SEVERAL KIDNEY DISEASES SUGGESTS THAT THIS PILLAR OF INNATE IMMUNITY HAS A CRITICAL ROLE IN THE PATHOPHYSIOLOGY OF RENAL DAMAGE OF DIFFERENT ETIOLOGIES. A GROWING BODY OF EXPERIMENTAL EVIDENCE INDICATES THAT COMPLEMENT ACTIVATION CONTRIBUTES TO THE PATHOGENESIS OF ACUTE KIDNEY INJURY (AKI) SUCH AS DELAYED GRAFT FUNCTION (DGF) IN TRANSPLANT PATIENTS. AKI IS CHARACTERIZED BY THE RAPID LOSS OF THE KIDNEY'S EXCRETORY FUNCTION AND IS A COMPLEX SYNDROME CURRENTLY LACKING A SPECIFIC MEDICAL TREATMENT TO ARREST OR ATTENUATE PROGRESSION IN CHRONIC KIDNEY DISEASE (CKD). RECENT EVIDENCE SUGGESTS THAT INDEPENDENTLY FROM THE INITIAL TRIGGER (I.E., SEPSIS OR ISCHEMIA/REPERFUSIONS INJURY), AN EPISODE OF AKI IS STRONGLY ASSOCIATED WITH AN INCREASED RISK OF SUBSEQUENT CKD. THE AKI-TO-CKD TRANSITION MAY INVOLVE A WIDE RANGE OF MECHANISMS INCLUDING SCAR-FORMING MYOFIBROBLASTS GENERATED FROM DIFFERENT SOURCES, MICROVASCULAR RAREFACTION, MITOCHONDRIAL DYSFUNCTION, OR CELL CYCLE ARREST BY THE INVOLVEMENT OF EPIGENETIC, GENE, AND PROTEIN ALTERATIONS LEADING TO COMMON FINAL SIGNALING PATHWAYS [I.E., TRANSFORMING GROWTH FACTOR BETA (TGF-BETA), P16 (INK4A) , WNT/BETA-CATENIN PATHWAY] INVOLVED IN RENAL AGING. RESEARCH IN RECENT YEARS HAS REVEALED THAT SEVERAL STRESSORS OR COMPLICATIONS SUCH AS REJECTION AFTER RENAL TRANSPLANTATION CAN LEAD TO ACCELERATED RENAL AGING WITH DETRIMENTAL EFFECTS WITH THE ESTABLISHMENT OF CHRONIC PROINFLAMMATORY CELLULAR PHENOTYPES WITHIN THE KIDNEY. DESPITE A GREATER UNDERSTANDING OF THESE MECHANISMS, THE ROLE OF COMPLEMENT SYSTEM IN THE CONTEXT OF THE AKI-TO-CKD TRANSITION AND RENAL INFLAMMAGING IS STILL POORLY EXPLORED. THE PURPOSE OF THIS REVIEW IS TO SUMMARIZE RECENT FINDINGS DESCRIBING THE ROLE OF COMPLEMENT IN AKI-TO-CKD TRANSITION. WE WILL ALSO ADDRESS HOW AND WHEN COMPLEMENT INHIBITORS MIGHT BE USED TO PREVENT AKI AND CKD PROGRESSION, THEREFORE IMPROVING GRAFT FUNCTION. 2020 9 1048 34 CLINICAL EPIGENETICS AND ACUTE/CHRONIC REJECTION IN SOLID ORGAN TRANSPLANTATION: AN UPDATE. THE LACK OF A PRECISE STRATIFICATION ALGORITHM FOR PREDICTING PATIENTS AT HIGH RISK OF GRAFT REJECTION CHALLENGES THE CURRENT SOLID ORGAN TRANSPLANTATION (SOT) CLINICAL SETTING. IN FACT, THE ESTABLISHED BIOMARKERS FOR TRANSPLANTATION OUTCOMES ARE UNABLE TO ACCURATELY PREDICT THE ONSET TIME AND SEVERITY OF GRAFT REJECTION (ACUTE OR CHRONIC) AS WELL AS THE INDIVIDUAL RESPONSE TO IMMUNOSUPPRESSIVE DRUGS. THUS, IDENTIFYING NOVEL MOLECULAR PATHWAYS UNDERLYING EARLY IMMUNOLOGICAL RESPONSES WHICH CAN DAMAGE TRANSPLANT INTEGRITY IS NEEDED TO REACH PRECISION MEDICINE AND PERSONALIZED THERAPY OF SOT. DIRECT EPIGENETIC-SENSITIVE MECHANISMS, MAINLY DNA METHYLATION AND HISTONE MODIFICATIONS, MAY PLAY A RELEVANT ROLE FOR IMMUNE ACTIVATION AND LONG-TERM EFFECTS (E.G., ACTIVATION OF FIBROTIC PROCESSES) WHICH MAY BE TRANSLATED IN NEW NON-INVASIVE BIOMARKERS AND DRUG TARGETS. IN PARTICULAR, THE MEASURE OF DNA METHYLATION BY USING THE BLOOD-BASED "EPIGENETIC CLOCK" SYSTEM MAY BE AN ADDED VALUE TO THE DONOR ELIGIBILITY CRITERIA PROVIDING AN ESTIMATION OF THE HEART BIOLOGICAL AGE AS WELL AS A PREDICTIVE BIOMARKERS. BESIDES, MONITORING OF DNA METHYLATION CHANGES MAY AID TO PREDICT ACUTE VS CHRONIC GRAFT DAMAGE IN KIDNEY TRANSPLANTATION (KT) PATIENTS. FOR EXAMPLE, HYPERMETHYLATION OF GENES BELONGING TO THE NOTCH AND WNT PATHWAYS SHOWED A HIGHER PREDICTIVE VALUE FOR CHRONIC INJURY OCCURRING AT 12 MONTHS POST-KT WITH RESPECT TO ESTABLISHED CLINICAL PARAMETERS. DETECTING HIGHER CIRCULATING CELL-FREE DNA (CFDNA) FRAGMENTS CARRYING HEPATOCYTE-SPECIFIC UNMETHYLATED LOCI IN THE INTER-ALPHA-TRYPSIN INHIBITOR HEAVY CHAIN 4 (ITIH4), INSULIN LIKE GROWTH FACTOR 2 RECEPTOR (IGF2R), AND VITRONECTIN (VTN) GENES MAY BE USEFUL TO PREDICT ACUTE GRAFT INJURY AFTER LIVER TRANSPLANTATION (LT) IN SERUM SAMPLES. FURTHERMORE, HYPOMETHYLATION IN THE FORKHEAD BOX P3 (FOXP3) GENE MAY SERVE AS A MARKER OF INFILTRATING NATURAL TREG PERCENTAGE IN THE GRAFT PROVIDING THE ABILITY TO PREDICT ACUTE REJECTION EVENTS AFTER HEART TRANSPLANTATION (HTX). WE AIM TO UPDATE ON THE POSSIBLE CLINICAL RELEVANCE OF DNA METHYLATION CHANGES REGULATING IMMUNE-RELATED PATHWAYS UNDERLYING ACUTE OR CHRONIC GRAFT REJECTION IN KT, LT, AND HTX WHICH MIGHT BE USEFUL TO PREVENT, MONITOR, AND TREAT SOLID ORGAN REJECTION AT PERSONALIZED LEVEL. 2021 10 2286 28 EPIGENETIC REGULATION IN KIDNEY TRANSPLANTATION. KIDNEY TRANSPLANTATION IS A STANDARD CARE FOR END STAGE RENAL DISEASE, BUT IT IS ALSO ASSOCIATED WITH A COMPLEX PATHOGENESIS INCLUDING ISCHEMIA-REPERFUSION INJURY, INFLAMMATION, AND DEVELOPMENT OF FIBROSIS. OVER THE PAST DECADE, ACCUMULATING EVIDENCE HAS SUGGESTED A ROLE OF EPIGENETIC REGULATION IN KIDNEY TRANSPLANTATION, INVOLVING DNA METHYLATION, HISTONE MODIFICATION, AND VARIOUS KINDS OF NON-CODING RNAS. HERE, WE ANALYZE THESE RECENT STUDIES SUPPORTING THE ROLE OF EPIGENETIC REGULATION IN DIFFERENT PATHOLOGICAL PROCESSES OF KIDNEY TRANSPLANTATION, I.E., ISCHEMIA-REPERFUSION INJURY, ACUTE REJECTION, AND CHRONIC GRAFT PATHOLOGIES INCLUDING RENAL INTERSTITIAL FIBROSIS. FURTHER INVESTIGATION OF EPIGENETIC ALTERATIONS, THEIR PATHOLOGICAL ROLES AND UNDERLYING MECHANISMS IN KIDNEY TRANSPLANTATION MAY LEAD TO NEW STRATEGIES FOR THE DISCOVERY OF NOVEL DIAGNOSTIC BIOMARKERS AND THERAPEUTIC INTERVENTIONS. 2022 11 3861 30 ISOLATION OF HUMAN ANTIGEN-SPECIFIC REGULATORY T CELLS WITH HIGH SUPPRESSIVE FUNCTION. ADOPTIVE TRANSFER OF REGULATORY T (TREG) CELLS COULD BE AN ALTERNATIVE TO CHRONIC IMMUNOSUPPRESSION FOR PREVENTION OF ALLOGENEIC GRAFT REJECTION. WHILE POLYSPECIFIC TREG CELLS CAN PREVENT IMMUNE RESPONSES UNDER LYMPHOPENIC CONDITIONS, AG-SPECIFIC TREG CELLS ARE NEEDED TO TREAT AUTOIMMUNITY AND GRAFT REJECTION. YET, RELIABLE MARKERS FOR AG-SPECIFIC TREG CELLS ARE MISSING. WE REPORT THAT LATENCY-ASSOCIATED PEPTIDE (LAP) AND GLYCOPROTEIN A REPETITIONS PREDOMINANT (GARP) CAN IDENTIFY HUMAN AG-SPECIFIC TREG CELLS. IN ADDITION, WE SHOW THAT THE DEPLETION OF CD154(+) CELLS FROM LAP(+) OR GARP(+) TREG CELLS INCREASES THE TREG-CELL PURITY TO OVER 90%, AS ASSESSED BY EPIGENETIC ANALYSIS. THESE AG-SPECIFIC TREG CELLS CAN BE ISOLATED MAGNETICALLY AND MIGHT CONTRIBUTE TO THE DEVELOPMENT OF GMP-BASED PROTOCOLS. IN ADDITION, AG-SPECIFIC TREG CELLS ARE FUNCTIONALLY FAR SUPERIOR TO CD4(+) CD25(HIGH) OR CD4(+) CD25(HIGH) CD127(LOW) TREG CELLS IN VITRO AND IN PREVENTING STRONG ALLOREACTIONS IN HUMANIZED MICE. THEY COULD, THEREFORE, HAVE A HIGH THERAPEUTIC POTENTIAL FOR THE CONTROL OF ALLOIMMUNE, AUTOIMMUNE, AND ALLERGIC IMMUNE RESPONSES IN PATIENTS. 2014 12 5900 39 T-CELL EXHAUSTION IN ORGAN TRANSPLANTATION. EXHAUSTION OF T CELLS OCCURS IN RESPONSE TO LONG-TERM EXPOSURE TO SELF AND FOREIGN ANTIGENS. IT LIMITS T CELL CAPACITY TO PROLIFERATE AND PRODUCE CYTOKINES, LEADING TO AN IMPAIRED ABILITY TO CLEAR CHRONIC INFECTIONS OR ERADICATE TUMORS. T-CELL EXHAUSTION IS ASSOCIATED WITH A SPECIFIC TRANSCRIPTIONAL, EPIGENETIC, AND METABOLIC PROGRAM AND CHARACTERISTIC CELL SURFACE MARKERS' EXPRESSION. RECENT STUDIES HAVE BEGUN TO ELUCIDATE THE ROLE OF T-CELL EXHAUSTION IN TRANSPLANT. HIGHER LEVELS OF EXHAUSTED T CELLS HAVE BEEN ASSOCIATED WITH BETTER GRAFT FUNCTION IN KIDNEY TRANSPLANT RECIPIENTS. IN CONTRAST, REINVIGORATING EXHAUSTED T CELLS BY IMMUNE CHECKPOINT BLOCKADE THERAPIES, WHILE PROMOTING TUMOR CLEARANCE, INCREASES THE RISK OF ACUTE REJECTION. LYMPHOCYTE DEPLETION AND HIGH ALLOANTIGEN LOAD HAVE BEEN IDENTIFIED AS MAJOR DRIVERS OF T-CELL EXHAUSTION. THIS COULD ACCOUNT, AT LEAST IN PART, FOR THE REDUCED RATES OF ACUTE REJECTION IN ORGAN TRANSPLANT RECIPIENTS INDUCED WITH THYMOGLOBULIN AND FOR THE PRO-TOLEROGENIC EFFECTS OF A LARGE ORGAN SUCH AS THE LIVER. AMONG THE DRUGS THAT ARE WIDELY USED FOR MAINTENANCE IMMUNOSUPPRESSION, CALCINEURIN INHIBITORS HAVE A CONTRASTING INHIBITORY EFFECT ON EXHAUSTION OF T CELLS, WHILE THE INFLUENCE OF MTOR INHIBITORS IS STILL UNCLEAR. HARNESSING OR ENCOURAGING THE NATURAL PROCESSES OF EXHAUSTION MAY PROVIDE A NOVEL STRATEGY TO PROMOTE GRAFT SURVIVAL AND TRANSPLANTATION TOLERANCE. 2022 13 1253 27 CURRENT PROBLEMS AND FUTURE DIRECTIONS OF TRANSFUSION-INDUCED ALLOIMMUNIZATION: SUMMARY OF AN NHLBI WORKING GROUP. IN APRIL 2010, A WORKING GROUP SPONSORED BY THE NATIONAL HEART, LUNG, AND BLOOD INSTITUTE WAS ASSEMBLED TO IDENTIFY RESEARCH STRATEGIES TO IMPROVE OUR UNDERSTANDING OF ALLOIMMUNIZATION CAUSED BY THE TRANSFUSION OF ALLOGENEIC BLOOD COMPONENTS AND TO EVALUATE POTENTIAL APPROACHES TO BOTH REDUCE ITS OCCURRENCE AND MANAGE ITS EFFECTS. SIGNIFICANT SEQUELAE OF ALLOIMMUNIZATION WERE DISCUSSED AND IDENTIFIED, INCLUDING DIFFICULTIES IN MAINTAINING CHRONIC TRANSFUSION OF RED BLOOD CELLS AND PLATELETS, HEMOLYTIC DISEASE OF THE NEWBORN, NEONATAL ALLOIMMUNE THROMBOCYTOPENIA, AND REJECTION OF TRANSPLANTED CELLS AND TISSUES. THE DISCUSSIONS RESULTED IN A CONSENSUS THAT IDENTIFIED KEY AREAS OF FUTURE RESEARCH AND DEVELOPMENTAL AREAS, INCLUDING GENETIC AND EPIGENETIC RECIPIENT FACTORS THAT REGULATE ALLOIMMUNIZATION, BIOCHEMICAL SPECIFICS OF TRANSFUSED PRODUCTS THAT AFFECT ALLOIMMUNIZATION, AND NOVEL TECHNOLOGIES FOR HIGH-THROUGHPUT GENOTYPING TO FACILITATE EXTENSIVE AND EFFICIENT ANTIGEN MATCHING BETWEEN DONOR AND RECIPIENT. ADDITIONAL AREAS OF IMPORTANCE INCLUDED ANALYSIS OF UNAPPRECIATED MEDICAL SEQUELAE OF ALLOIMMUNIZATION, SUCH AS CELLULAR IMMUNITY AND ITS EFFECT UPON TRANSPLANT AND AUTOIMMUNITY. IN ADDITION, SUPPORT FOR RESEARCH INFRASTRUCTURE WAS DISCUSSED, WITH AN EMPHASIS ON ENCOURAGING COLLABORATION AND SYNERGY OF ANIMAL MODELS BIOLOGY AND HUMAN CLINICAL RESEARCH. FINALLY, TRAINING FUTURE INVESTIGATORS WAS IDENTIFIED AS AN AREA OF IMPORTANCE. IN AGGREGATE, THIS COMMUNICATION PROVIDES A SYNOPSIS OF THE OPINIONS OF THE WORKING GROUP ON THE ABOVE ISSUES AND PRESENTS BOTH A LIST OF SUGGESTED PRIORITIES AND THE RATIONALE FOR THE TOPICS OF FOCUS. THE AREAS OF RESEARCH IDENTIFIED IN THIS REPORT REPRESENT POTENTIAL FERTILE GROUND FOR THE MEDICAL ADVANCEMENT OF PREVENTING AND MANAGING ALLOIMMUNIZATION IN ITS DIFFERENT FORMS AND MITIGATING THE CLINICAL PROBLEMS IT PRESENTS TO MULTIPLE PATIENT POPULATIONS. 2011 14 3872 27 JUVENILE MYELOMONOCYTIC LEUKEMIA-A COMPREHENSIVE REVIEW AND RECENT ADVANCES IN MANAGEMENT. JUVENILE MYELOMONOCYTIC LEUKEMIA (JMML) IS A RARE PEDIATRIC MYELODYSPLASTIC/MYELOPROLIFERATIVE NEOPLASM OVERLAP DISEASE. JMML IS ASSOCIATED WITH MUTATIONS IN THE RAS PATHWAY GENES RESULTING IN THE MYELOID PROGENITORS BEING SENSITIVE TO GRANULOCYTE MONOCYTE COLONY-STIMULATING FACTOR (GM-CSF). KARYOTYPE ABNORMALITIES AND ADDITIONAL EPIGENETIC ALTERATIONS CAN ALSO BE FOUND IN JMML. NEUROFIBROMATOSIS AND NOONAN'S SYNDROME HAVE A PREDISPOSITION FOR JMML. IN A FEW PATIENTS, THE RAS GENES (NRAS, KRAS, AND PTPN11) ARE MUTATED AT THE GERMLINE AND THIS USUALLY RESULTS IN A TRANSIENT MYELOPROLIFERATIVE DISORDER WITH A GOOD PROGNOSIS. JMML WITH SOMATIC RAS MUTATION BEHAVES AGGRESSIVELY. JMML PRESENTS WITH CYTOPENIAS AND LEUKEMIC INFILTRATION INTO ORGANS. THE LABORATORY FINDINGS INCLUDE HYPERLEUKOCYTOSIS, MONOCYTOSIS, INCREASED HEMOGLOBIN-F LEVELS, AND CIRCULATING MYELOID PRECURSORS. THE BLAST CELLS IN THE PERIPHERAL BLOOD/BONE-MARROW ASPIRATE ARE LESS THAN 20% AND THE ABSENCE OF THE BCR-ABL TRANSLOCATION HELPS TO DIFFERENTIATE FROM CHRONIC MYELOID LEUKEMIA. JMML SHOULD BE DIFFERENTIATED FROM IMMUNODEFICIENCIES, VIRAL INFECTIONS, INTRAUTERINE INFECTIONS, HEMOPHAGOLYMPHOHISTIOCYTOSIS, OTHER MYELOPROLIFERATIVE DISORDERS, AND LEUKEMIAS. CHEMOTHERAPY IS EMPLOYED AS A BRIDGE TO HSCT, EXCEPT IN FEW WITH LESS AGGRESSIVE DISEASE, IN WHICH CHEMOTHERAPY ALONE CAN RESULT IN LONG TERM REMISSION. AZACITIDINE HAS SHOWN PROMISE AS A SINGLE AGENT TO STABILIZE THE DISEASE. THE PROGNOSIS OF JMML IS POOR WITH ABOUT 50% OF PATIENTS SURVIVING AFTER AN ALLOGENEIC HEMATOPOIETIC STEM CELL TRANSPLANT (HSCT). ALLOGENEIC HSCT IS THE ONLY KNOWN CURE FOR JMML TO DATE. MYELOABLATIVE CONDITIONING IS MOST COMMONLY USED WITH GRAFT VERSUS HOST DISEASE (GVHD) PROPHYLAXIS TAILORED TO THE AGGRESSIVENESS OF THE DISEASE. RELAPSES ARE COMMON EVEN AFTER HSCT AND A SECOND HSCT CAN SALVAGE A THIRD OF THESE PATIENTS. NOVEL OPTIONS IN THE TREATMENT OF JMML E.G., HYPOMETHYLATING AGENTS, MEK INHIBITORS, JAK INHIBITORS, TYROSINE KINASE INHIBITORS, ETC. ARE BEING EXPLORED. 2021 15 6013 49 THE APPLICATIONS OF DNA METHYLATION AS A BIOMARKER IN KIDNEY TRANSPLANTATION: A SYSTEMATIC REVIEW. BACKGROUND: ALTHOUGH KIDNEY TRANSPLANTATION IMPROVES PATIENT SURVIVAL AND QUALITY OF LIFE, LONG-TERM RESULTS ARE HAMPERED BY BOTH IMMUNE- AND NON-IMMUNE-MEDIATED COMPLICATIONS. CURRENT BIOMARKERS OF POST-TRANSPLANT COMPLICATIONS, SUCH AS ALLOGRAFT REJECTION, CHRONIC RENAL ALLOGRAFT DYSFUNCTION, AND CUTANEOUS SQUAMOUS CELL CARCINOMA, HAVE A SUBOPTIMAL PREDICTIVE VALUE. DNA METHYLATION IS AN EPIGENETIC MODIFICATION THAT DIRECTLY AFFECTS GENE EXPRESSION AND PLAYS AN IMPORTANT ROLE IN PROCESSES SUCH AS ISCHEMIA/REPERFUSION INJURY, FIBROSIS, AND ALLOREACTIVE IMMUNE RESPONSE. NOVEL TECHNIQUES CAN QUICKLY ASSESS THE DNA METHYLATION STATUS OF MULTIPLE LOCI IN DIFFERENT CELL TYPES, ALLOWING A DEEP AND INTERESTING STUDY OF CELLS' ACTIVITY AND FUNCTION. THEREFORE, DNA METHYLATION HAS THE POTENTIAL TO BECOME AN IMPORTANT BIOMARKER FOR PREDICTION AND MONITORING IN KIDNEY TRANSPLANTATION. PURPOSE OF THE STUDY: THE AIM OF THIS STUDY WAS TO EVALUATE THE ROLE OF DNA METHYLATION AS A POTENTIAL BIOMARKER OF GRAFT SURVIVAL AND COMPLICATIONS DEVELOPMENT IN KIDNEY TRANSPLANTATION. MATERIAL AND METHODS: A SYSTEMATIC REVIEW OF SEVERAL DATABASES HAS BEEN CONDUCTED. THE NEWCASTLE-OTTAWA SCALE AND THE JADAD SCALE HAVE BEEN USED TO ASSESS THE RISK OF BIAS FOR OBSERVATIONAL AND RANDOMIZED STUDIES, RESPECTIVELY. RESULTS: TWENTY ARTICLES REPORTING ON DNA METHYLATION AS A BIOMARKER FOR KIDNEY TRANSPLANTATION WERE INCLUDED, ALL USING DNA METHYLATION FOR PREDICTION AND MONITORING. DNA METHYLATION PATTERN ALTERATIONS IN CELLS ISOLATED FROM DIFFERENT TISSUES, SUCH AS KIDNEY BIOPSIES, URINE, AND BLOOD, HAVE BEEN ASSOCIATED WITH ISCHEMIA-REPERFUSION INJURY AND CHRONIC RENAL ALLOGRAFT DYSFUNCTION. THESE ALTERATIONS OCCURRED IN DIFFERENT AND SPECIFIC LOCI. DNA METHYLATION STATUS HAS ALSO PROVED TO BE IMPORTANT FOR IMMUNE RESPONSE MODULATION, HAVING A CRUCIAL ROLE IN REGULATORY T CELL DEFINITION AND ACTIVITY. RESEARCH ALSO FOCUSED ON A BETTER UNDERSTANDING OF THE ROLE OF THIS EPIGENETIC MODIFICATION ASSESSMENT FOR REGULATORY T CELLS ISOLATION AND EXPANSION FOR FUTURE TOLERANCE INDUCTION-ORIENTED THERAPIES. CONCLUSIONS: STUDIES INCLUDED IN THIS REVIEW ARE HETEROGENEOUS IN STUDY DESIGN, BIOLOGICAL SAMPLES, AND OUTCOME. MORE COORDINATED INVESTIGATIONS ARE NEEDED TO AFFIRM DNA METHYLATION AS A CLINICALLY RELEVANT BIOMARKER IMPORTANT FOR PREVENTION, MONITORING, AND INTERVENTION. 2022 16 274 27 AGE-RELATED CHANGES IN DNA METHYLATION AFFECT RENAL HISTOLOGY AND POST-TRANSPLANT FIBROSIS. DURING AGEING, KIDNEY FUNCTION DECREASES DUE TO RENAL TUBULAR ATROPHY, INTERSTITIAL FIBROSIS, GLOMERULOSCLEROSIS AND ARTERIOSCLEROSIS. RECENTLY, CHANGES IN DNA METHYLATION WERE SHOWN TO CONTRIBUTE TO VARIOUS AGEING PROCESSES. HOWEVER, IT IS UNKNOWN WHETHER SUCH CHANGES ALSO CONTRIBUTE TO AGE-RELATED KIDNEY DYSFUNCTION. TO ASSESS THIS, WE PROFILED GENOME-WIDE CHANGES IN DNA METHYLATION (OVER 800 000 CPG SITES) IN 95 RENAL BIOPSIES OBTAINED PRIOR TO KIDNEY TRANSPLANTATION FROM DONORS AGED 16 TO 73 YEARS. DONOR AGE SIGNIFICANTLY ASSOCIATED WITH THE METHYLATION OF 92 778 CPGS (FALSE DISCOVERY RATE UNDER 0.05), CORRESPONDING TO 10 285 DIFFERENTIALLY METHYLATED REGIONS. THESE REGIONS WERE MOST FREQUENTLY LOCATED IN GENES INVOLVED IN THE WNT/BETA-CATENIN SIGNALING PATHWAY. USING AN INDEPENDENT COHORT OF 67 BIOPSIES, WE AUTONOMOUSLY VALIDATED THESE FINDINGS. INTERESTINGLY, THE METHYLATION STATUS OF THESE 92 778 AGE-RELATED CPGS WAS ASSOCIATED WITH GLOMERULOSCLEROSIS (34.4% OF CPGS AT A FALSE DISCOVERY RATE UNDER 0.05) AND INTERSTITIAL FIBROSIS (0.9%) AND GRAFT FUNCTION AT ONE YEAR AFTER TRANSPLANTATION, BUT NOT WITH TUBULAR ATROPHY AND ARTERIOSCLEROSIS. NO ASSOCIATION WAS OBSERVED WITH ANY OF THESE PATHOLOGIES AT THE TIME OF TRANSPLANTATION (0% AT A FALSE DISCOVERY RATE UNDER 0.05). THUS, AGE-ASSOCIATED CHANGES IN DNA METHYLATION AT THE TIME OF TRANSPLANTATION PREDICT FUTURE INJURY OF TRANSPLANTED KIDNEYS. SPECIFICALLY, OUR EPIGENOME-WIDE ASSOCIATION STUDY DEMONSTRATES THAT EPIGENETIC RENAL AGEING IS IMPLICATED IN PROGRESSIVE FIBROSIS IN BOTH THE GLOMERULUS AND THE INTERSTITIUM. 2019 17 2211 31 EPIGENETIC MODIFICATIONS AND THE DEVELOPMENT OF KIDNEY GRAFT FIBROSIS. PURPOSE OF REVIEW: TO OUTLINE RECENT DISCOVERIES IN EPIGENETIC REGULATORY MECHANISMS THAT HAVE POTENTIAL IMPLICATIONS IN THE DEVELOPMENT OF RENAL FIBROSIS FOLLOWING KIDNEY TRANSPLANTATION. RECENT FINDINGS: THE CHARACTERIZATION OF RENAL FIBROSIS FOLLOWING KIDNEY TRANSPLANTATION HAS SHOWN TGFBETA/SMAD SIGNALING TO PLAY A MAJOR ROLE IN THE PROGRESSION TO CHRONIC ALLOGRAFT DYSFUNCTION. THE ONSET OF UNREGULATED PROINFLAMMATORY PATHWAYS ARE ONLY EXACERBATED BY THE DECLINE IN REGULATORY MECHANISMS LOST WITH PROGRESSIVE PATIENT AGE AND COMORBIDITIES SUCH AS HYPERTENSION AND DIABETES. HOWEVER, SIGNIFICANT DEVELOPMENTS IN THE RECOGNITION OF EPIGENETIC REGULATORY MARKERS UPSTREAM OF ABERRANT TGFBETA-SIGNALING HAS SIGNIFICANT CLINICAL POTENTIAL TO PROVIDE THERAPEUTIC TARGETS FOR THE TREATMENT OF RENAL FIBROSIS. IN ADDITION, DISCOVERIES IN EXTRACELLULAR VESICLES AND THE CHARACTERIZATION OF THEIR CARGO HAS LAID NEW FRAMEWORK FOR THE POTENTIAL TO EVALUATE PATIENT OUTCOMES INDEPENDENT OF INVASIVE BIOPSIES. SUMMARY: THE CURRENT REVIEW SUMMARIZES THE MAIN FINDINGS IN EPIGENETIC MACHINERY SPECIFIC TO THE DEVELOPMENT OF RENAL FIBROSIS AND HIGHLIGHTS THERAPEUTIC OPTIONS THAT HAVE SIGNIFICANT POTENTIAL TO TRANSLATE INTO CLINICAL PRACTICE. 2021 18 2268 30 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 19 1469 21 DISTINCT EVOLUTIONARY PATHS IN CHRONIC LYMPHOCYTIC LEUKEMIA DURING RESISTANCE TO THE GRAFT-VERSUS-LEUKEMIA EFFECT. LEUKEMIC RELAPSE REMAINS A MAJOR BARRIER TO SUCCESSFUL ALLOGENEIC HEMATOPOIETIC STEM CELL TRANSPLANTATION (ALLO-HSCT) FOR AGGRESSIVE HEMATOLOGIC MALIGNANCIES. THE BASIS FOR RELAPSE OF ADVANCED LYMPHOID MALIGNANCIES REMAINS INCOMPLETELY UNDERSTOOD AND MAY INVOLVE ESCAPE FROM THE GRAFT-VERSUS-LEUKEMIA (GVL) EFFECT. WE HYPOTHESIZED THAT FOR PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) TREATED WITH ALLO-HSCT, LEUKEMIC CELL-INTRINSIC FEATURES INFLUENCE TRANSPLANT OUTCOMES BY DIRECTING THE EVOLUTIONARY TRAJECTORIES OF CLL CELLS. INTEGRATED GENETIC, TRANSCRIPTOMIC, AND EPIGENETIC ANALYSES OF CLL CELLS FROM 10 PATIENTS REVEALED THAT THE CLINICAL KINETICS OF POST-HSCT RELAPSE ARE SHAPED BY DISTINCT MOLECULAR DYNAMICS. EARLY RELAPSES AFTER ALLO-HSCT EXHIBITED NOTABLE GENETIC STABILITY; SINGLE CLL CELL TRANSCRIPTIONAL ANALYSIS DEMONSTRATED A CELLULAR HETEROGENEITY THAT WAS STATIC OVER TIME. IN CONTRAST, CLL CELLS RELAPSING LATE AFTER ALLO-HSCT DISPLAYED NOTABLE GENETIC EVOLUTION AND EVIDENCE OF NEOANTIGEN DEPLETION, CONSISTENT WITH MARKED SINGLE-CELL TRANSCRIPTIONAL SHIFTS THAT WERE UNIQUE TO EACH PATIENT. WE OBSERVED A GREATER RATE OF EPIGENETIC CHANGE FOR LATE RELAPSES NOT SEEN IN EARLY RELAPSES OR RELAPSES AFTER CHEMOTHERAPY ALONE, SUGGESTING THAT THE SELECTION PRESSURES OF THE GVL BOTTLENECK ARE UNLIKE THOSE IMPOSED BY CHEMOTHERAPY. NO SELECTIVE ADVANTAGE FOR HUMAN LEUKOCYTE ANTIGEN (HLA) LOSS WAS OBSERVED, EVEN WHEN PRESENT IN PRETRANSPLANT SUBPOPULATIONS. GAIN OF STEM CELL MODULES WAS A COMMON SIGNATURE ASSOCIATED WITH LEUKEMIA RELAPSE REGARDLESS OF POSTTRANSPLANT RELAPSE KINETICS. THESE DATA ELUCIDATE THE BIOLOGICAL PATHWAYS THAT UNDERLIE GVL RESISTANCE AND POSTTRANSPLANT RELAPSE. 2020 20 3013 22 GENETICS AND EPIGENETICS OF CHRONIC ALLOGRAFT DYSFUNCTION IN KIDNEY TRANSPLANTS. CHRONIC ALLOGRAFT DYSFUNCTION IS THE MOST COMMON CAUSE OF ALLOGRAFT LOST. CHRONIC ALLOGRAFT DYSFUNCTION HAPPENS AS A RESULT OF COMPLEX INTERACTIONS AT THE MOLECULAR AND CELLULAR LEVELS. GENETIC AND ENVIRONMENTAL FACTORS BOTH INFLUENCE THE EVOLUTION AND PROGRESSION OF THE CHRONIC ALLOGRAFT DYSFUNCTION. EPIGENETIC MODIFICATION COULD BE CONSIDERED AS A THERAPEUTICALLY MODIFIABLE ELEMENT TO PAUSE THE FIBROSIS PROCESS THROUGH NOVEL STRATEGIES. IN THIS REVIEW, THE PUBMED DATABASE WAS SEARCHED FOR ENGLISH-LANGUAGE ARTICLES ON THESE NEW AREAS. 2016