Leishmaniasis is a neglected tropical disease caused by protozoan parasites of the genus Leishmania. Currently, no licensed human vaccine is available and increasing drug resistance continues to compromise the disease control. The present study aimed to computationally design and evaluate a multi-epitope vaccine candidate targeting the conserved amastin protein of Leishmania donovani (UniProt ID: A5XDA6) using an integrated immunoinformatics approach. Cytotoxic T lymphocyte (CTL), helper T lymphocyte (HTL) and B cell epitopes were predicted and sequentially prioritized on the basis of HLA-binding affinity, antigenicity, allergenicity and molecular docking with their respective HLA molecules. A total of twelve epitopes (five CTL, four HTL and three B cell epitopes) were selected. Conservancy analysis demonstrated that most epitopes were highly conserved across L.donovani, L. infantum and L. major, while population coverage analysis predicted 81.61% global coverage. The selected epitopes were assembled into a 209-amino acid vaccine construct using AAY, GPGPG and KK linkers with the TLR4 agonist RS-09 as an adjuvant. The construct was predicted to be antigenic, non-allergenic, stable and soluble whereas structural validation confirmed a high-quality three-dimensional model. Molecular docking demonstrated favourable interaction with the TLR4 receptor, while discontinuous B cell epitope analysis revealed structural similarity between the vaccine construct and the native amastin protein. Normal mode analysis, molecular dynamics simulation and immune simulation further supported the structural stability and immunogenic potential of the vaccine construct. A 100 ns molecular dynamics simulation confirmed the structural stability of the vaccine-TLR4 complex and MM/PBSA and MM/GBSA binding free energy analyses further supported favourable binding affinity between the vaccine construct and TLR4. Codon optimization and in silico cloning indicated favourable expression in the Escherichia coli pET-28a (+) expression system. These computational findings suggest that the proposed multi-epitope vaccine is a promising candidate which requires further experimental validation for realizing its potential as a vaccine against leishmaniasis.
Human leukocyte antigen G (HLA G) is a non-classical HLA class I molecule with, potent tolerogenic activity, mainly restricted to immune-privileged tissues under, physiological conditions. However, aberrant HLA G expression has been increasingly, reported in tumors, where it acts as an immune checkpoint contributing to evasion from, cytotoxic T and NK cell responses. In this review, we integrate current knowledge on, the molecular regulation and immunological roles of HLA G with original findings from, gastric and colorectal adenocarcinoma cohorts of similar demographic and geographic, origin. Genetic analyses revealed that polymorphisms associated with increased HLA,G expression such as the 14 bp deletion and + 3142C variants in the 3'UTR, region-were significantly enriched in gastric cancer but not in colorectal cancer, suggesting tissue-specific genetic modulation of HLA G expression. Immunohistochemical examination of tumor samples showed that HLA G protein, expression was present in both gastric (41.2%) and colorectal (36.4%), adenocarcinomas, while absent from matched non-tumoral mucosa. Strikingly, HLA G, positivity correlated with histologically undifferentiated tumor subtypes (diffuse or grade, 3), indicating that dedifferentiation is a key determinant of its expression. These HLA, G-high tumors likely generate an immunosuppressive microenvironment through the, HLA G/ILT2 axis, functionally impairing ILT2+ cytotoxic T lymphocytes analogously to, classical PD 1/PD L1 pathways. Altogether, our data suggest that tumor dedifferentiation and loss of epithelial identity promote HLA G induction, endowing, tumors with stem like, immune resistant properties. Consequently, HLA G expression, and its receptor interactions emerge as potential biomarkers of poor prognosis and, feasible targets for therapeutic blockade in gastrointestinal cancers, particularly those, refractory to conventional immune checkpoint inhibitors.
Children with failed kidney transplant often become highly sensitized to human leukocyte antigens (HLA), limiting access to future transplantation. We report a successful accelerated peri-transplant desensitization protocol enabling HLA-incompatible deceased donor kidney transplantation in a highly sensitized pediatric recipient. A 14-year-old boy remained on hemodialysis for 11 years after failure of his first kidney transplant and had a calculated panel reactive antibody of 99.70%. Following an offer from a haplotype-matched deceased donor, he was found to have class I and class II donor-specific antibodies and a positive flow cytometry crossmatch. Accelerated desensitization over 6 days consisted of three plasmapheresis sessions followed by intravenous immunoglobulin and rituximab. Alemtuzumab was used as induction agent for transplant. Crossmatch reactivity decreased to an acceptable threshold, permitting transplantation. At 12 months, mixed T-cell- and antibody-mediated rejection occurred despite stable donor-specific antibodies. Graft function remained stable at 43 mL/min/1.73 m2 at 15 months post-transplant.
BACKGROUND:Acute graft-versus-host disease (aGVHD) remains a major complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). This study investigated the association between the graft CD3+/CD4 - CD8- T-cell ratio and the incidence of aGVHD in pediatric recipients. METHODS:A total of 112 pediatric patients with high-risk hematologic malignancies undergoing allo-HSCT were enrolled in this retrospective study. Associations between the graft CD3+/CD4 - CD8- T-cell ratio and aGVHD were evaluated using Fine-Gray regression models. Receiver operating characteristic (ROC) analysis was performed to determine the predictive performance and optimal cutoff value of the graft CD3+/CD4 - CD8- T-cell ratio. Spearman's rank correlation coefficient was used to assess correlations among different cellular subsets. RESULTS:The day-100 cumulative incidence of grade II-IV aGVHD was 41.1%. In multivariable analysis, the graft CD3+/CD4 - CD8- T-cell ratio was independently associated with grade II-IV aGVHD. ROC analysis identified 56 as the optimal cutoff value for the graft CD3+/CD4 - CD8- T-cell ratio. Patients with a high ratio had a significantly higher incidence of grade II-IV aGVHD than those with a low ratio (56.3% vs. 20.8%, P < 0.001), whereas no significant differences were observed in disease relapse or cytomegalovirus (CMV) infection. The graft CD4 - CD8- T-cell dose was positively correlated with early peripheral CD4 - CD8- T-cell recovery after transplantation. CONCLUSIONS:A higher graft CD3+/CD4 - CD8- T-cell ratio is independently associated with an increased risk of day-100 grade II-IV aGVHD in pediatric allo-HSCT recipients. Optimizing the graft CD3+/CD4 - CD8- T-cell ratio may help mitigate aGVHD, thereby serving as a practical biomarker for individualized aGVHD risk stratification.
The human leukocyte antigen (HLA) system is the most polymorphic gene complex in the human genome and plays a central role in susceptibility to autoimmune disease and drug hypersensitivity. HLA typing tools arcasHLA, T1K, HLA-HD and OptiType each emit a distinct output, creating a manual reformatting bottleneck. We present HLAnte, a Python command-line interface that parses all four formats, normalizes calls against a version-pinned IPD-IMGT/HLA database, and consolidates GWAS Catalog, PharmGKB, Clinical Pharmacogenetics Implementation Consortium (CPIC), and Allele Frequency Net Database (AFND) evidence in one provenance-tagged report. Across 2692 samples from the 1000 Genomes Project, parse rates were 99.8-99.9% and HLAnte matched 26,300 of 26,301 calls to an IPD-IMGT/HLA name; that is coverage, not specificity: only 0.75% of calls resolve to a single allele. We quantified annotation-retrieval fidelity, not clinical detection: CPIC Level 1A retrieval was 100% for four sentinel allele-drug pairs and disease-annotation retrieval 99.7-100% across seven allele-disease pairs. AFND coverage (the proportion of annotated calls with a population allele-frequency record for the sample's super-population) was 99.8-100% in every super-population with the full AFND snapshot. Three worked examples illustrate use: pharmacogenomic triage, population-referenced frequency reporting, and cohort disease-association screening. HLAnte is available under the MIT license (https://github.com/efe3506/HLAnte).
The human leukocyte antigen (HLA) allele and haplotype frequencies were calculated from 263,542 voluntary donors with medium- to high-resolution typing. This is the first study of a large sample with high-resolution HLA typing in the Thai population. The total numbers of two-field single alleles for HLA-A, -B, -C, -DRB1, and -DQB1 were 139, 198, 115, 80, and 24, respectively. The proportion of each HLA allele in Thais ranged from 1.54% to 3.45% of the total two-field HLA alleles in the IPD-IMGT/HLA database. The frequencies of alleles following common, intermediate, and well-documented (CIWD) groups for HLA-A, -B, -C,-DRB1, and -DQB1 were 69, 123, 55, 69, and 18, respectively. The CIWD percentages were 49.64%, 62.12%, 47.83%, 86.25%, and 75.0%, respectively. The alleles with a frequency greater than 5% were A*02:03, A*02:07, A*11:01, A*24:02, A*33:03, B*13:01, B*15:02, B*40:01, B*46:01, B*58:01, C*01:02, C*03:02, C*03:04, C*07:01, C*07:02, C*08:01, DRB1*03:01, DRB1*04:05, DRB1*07:01, DRB1*09:01, DRB1*12:02, DRB1*15:01, DRB1*15:02, DRB1*16:02, DQB1*02:01, DQB1*03:01, DQB1*03:02, DQB1*03:03, DQB1*05:01, DQB1*05:02, and DQB1*06:01. The haplotypes with a frequency greater than 2% were A*02:07 ∼ C*01:02 ∼ B*46:01 ∼ DRB1*09:01 ∼ DQB1*03:03, A*11:01 ∼ C*08:01 ∼ B*15:02 ∼ DRB1*12:02 ∼ DQB1*03:01, A*33:03 ∼ C*03:02 ∼ B*58:01 ∼ DRB1*03:01 ∼ DQB1*02:01,and A*33:03 ∼ C*07:01 ∼ B*44:03 ∼ DRB1*07:01 ∼ DQB1*02:01. These findings enable the registry to predict the opportunity to find well-matched organ and stem cell donors for patients with rare HLA typing.
Pro-inflammatory macrophage cell death is essential for resolving inflammation, yet the subtype-specific mechanisms governing this cell death remained unclear. Herein, THP-1-derived macrophages were polarized into pro-inflammatory (M1) or anti-inflammatory (M2) subtypes and exposed to lipopolysaccharide. M1 cells exhibited higher DNA fragmentation, caspase-3 cleavage, and lactate dehydrogenase release. Pharmacologic inhibition or genetic knockdown of caspase-2 effectively attenuated LPS-triggered M1 macrophage cell death. Mechanistic analyses excluded contributions of the mitochondrial apoptotic pathway, as no Bid cleavage, mitochondrial membrane potential dissipation, or rescue effect of cyclosporin A were detected. IFN-γ pretreatment enhanced caspase-8 cleavage, while caspase-2 deficiency consistently blocked caspase-8 activation under diverse death stimuli: LPS, etoposide, tumor necrosis factor-related apoptosis-inducing ligand, and hydrogen peroxide. IFN-γ priming alone triggered caspase-2 cleavage without inducing cell death, and this pre-activated caspase-2 pool strongly amplified subsequent LPS-mediated caspase-8 activation. Collectively, our work identifies a non-canonical, mitochondria-independent caspase-2/caspase-8 axis that selectively drives LPS-induced cell death in IFN-γ-primed THP-1 macrophages. This pathway acts as a self-regulatory feedback loop to eliminate hyper-inflammatory macrophages and maintain immune homeostasis, providing a novel mechanistic framework for understanding subtype-specific macrophage cell death.
Alopecia areata (AA) is a relapsing autoimmune disease characterized by non-scarring loss of hair following the collapse of immune privilege of the anagen hair follicles. This review summarizes recent molecular findings linking follicular stress to an atypical cytotoxic response, with special emphasis on the role of CD8 + NKG2D+ T cells, stress-induced ligands (MICA/ULBPs), and a Th1 cytokine circuit triggered by IFN-γ and IL-15, which communicates via the JAK/STAT pathway. We present new evidence that oxidative stress and mitochondrial dysfunction can enhance immune activation and may follow disease activity, generating the prospect of redox- and mitophagy-based adjunctive interventions. In addition to mechanisms, we discuss genetic susceptibility loci and high-throughput profiling, such as transcriptomics and proteomics, and describe how integrated multi-omics can be used to assist endotyping, prognostication, and biomarker-sensitive treatment selection. In treatment, AA is moving toward narrow-based agents rather than general immunosuppression and local agents. The efficacy standard is now set by JAK inhibitors, with baricitinib supported by landmark phase 3 studies demonstrating significantly increased scalp regrowth compared to placebo, and newer selective JAK inhibitors and IL-15-based or other immune checkpoint biologics are under development. Combination regimens based on immune signature, real-world safety surveillance, and strategies to achieve long-term immune tolerance and reestablish follicular immune privilege over short-term suppression are the key priorities in the future.
Given the central role of neuroinflammation in neurocysticercosis (NCC), IL10 promoter variation may influence susceptibility and disease expression. We analyzed rs1800896 (-1082 A > G), rs1800871 (-819C > T), and rs1800872 (-592C > A), together with reconstructed haplotypes/diplotypes, in 92 Mexican case-parent trios. Susceptibility was assessed by exact transmission disequilibrium testing, and exploratory case-only analyses evaluated cerebrospinal fluid (CSF) inflammatory status, parasite burden, location, degenerative stage, and disease-related symptoms. No SNP showed significant transmission distortion after correction for multiple comparisons. The rs1800896 G allele showed borderline over-transmission (38 transmitted vs. 22 non-transmitted; exact p = 0.052), but this was not significant after correction. In exploratory analyses, rs1800896 G dosage and the GCC haplotype showed associations with lower odds of inflammatory CSF before correction for multiple comparisons, whereas the ACC haplotype showed an uncorrected association with the presence of multiple brain parasites. None remained significant after false-discovery rate (FDR) or Bonferroni correction. No symptom-category association remained significant after correction. These data do not support a major role for the analyzed IL10 promoter variants in NCC susceptibility but suggest preliminary inflammatory and radiological signals requiring replication.
Epidermal growth factor receptor (EGFR) is overexpressed in more than 90% of head and neck squamous cell carcinoma (HNSCC) cases and plays a critical role in tumor progression, metastasis, and therapeutic resistance, making it an attractive target for immunotherapy. This study aimed to design and comprehensively evaluate a multi-epitope peptide vaccine targeting the extracellular domain of EGFR using an integrated immunoinformatics approach. Linear B-cell, helper T lymphocyte (HTL), and cytotoxic T lymphocyte (CTL) epitopes were predicted and screened for antigenicity, immunogenicity, allergenicity, toxicity, HLA binding affinity, population coverage, and IFN-γ induction. Selected epitopes were assembled into a multi-epitope vaccine construct and evaluated through structural modeling, molecular docking, molecular dynamics simulation, immune simulation, and codon optimization. Epitope conservancy was assessed across reviewed EGFR isoforms, followed by structural and HNSCC somatic mutation mapping. The vaccine construct exhibited favorable antigenic, non-allergenic, and non-toxic properties with broad predicted population coverage. Among the HTL epitopes, CQGTSNKLTQLGTFE was predicted to induce IFN-γ. Molecular docking and dynamics simulations demonstrated stable receptor interactions, whereas immune simulation predicted robust humoral and cellular immune responses. Six of the ten selected epitopes were completely conserved across all reviewed EGFR isoforms, while the remaining epitopes retained 75% conservancy. Importantly, none of the recurrent extracellular EGFR mutations identified in 619 profiled HNSCC tumors overlapped with the selected epitopes. These findings support the proposed EGFR-targeted multi-epitope vaccine as a promising immunotherapeutic candidate for HNSCC and provide a strong computational foundation for future experimental validation.
To characterize the clinical and immunological features of DOCK8 deficiency and better define its disease spectrum, we retrospectively analyzed 11 patients diagnosed at our hospital between 2014 and 2025. All patients presented in early childhood, most commonly with eczema and recurrent infections, and a higher rate of Epstein-Barr virus infection. Severe systemic infections, including sepsis and purulent meningitis, were observed in two patients at disease onset. Multisystem involvement was identified, including gastrointestinal, urinary, and cardiovascular abnormalities. Immunological evaluation showed reduced CD3+ and CD4+ T cells, decreased naïve T cells, and increased terminal effector memory T cells (TEMRA), which progressively accumulated during disease course. Eight patients underwent hematopoietic stem cell transplantation (HSCT): five achieved favorable outcomes, while three experienced severe complications, leading to two deaths. These findings indicate that DOCK8 deficiency is characterized by allergic manifestations, recurrent infections, and multisystem involvement, likely related to T-cell dysfunction. Early recognition and genetic diagnosis may facilitate timely consideration of HSCT and improve clinical outcomes.
OBJECTIVE:The present study was undertaken to determine the association of genetic variants of MMP-2 (-1306C/T and -735C/T), MMP-9 (-1562C/T), and TNF-α (-308G/A) with RSA risk or protection. METHODS:80 patients and 110 controls were enrolled for the study. Genotyping was carried out using PCR-RFLP method. Serum MMP-2 and MMP-9 activities were assessed by gelatin zymography. Data were analyzed statistically using SPSS, STATA and SHESis Plus. RESULTS:MMP-2 -1306C/T variant was associated with reduced RSA risk under codominant (p - 0.044), dominant (p - 0.042), and overdominant (p - 0.042) models. However, MMP-2 -735C/T and MMP-9-1562C/T variants were not associated with RSA. The T-C haplotype of MMP-2 variants was found to be associated with reduced RSA risk. Conversely, TNF-α -308G/A variant was strongly associated with increased RSA risk under codominant (p - 0.008), dominant (p - 0.011), and overdominant (p - 0.004) models. Gelatin zymography demonstrated elevated serum MMP-2 activity in patients as compared to controls. CONCLUSION:The findings indicate that MMP-2 -1306C/T variant may reduce and TNF-α -308G/A variant may increase RSA risk. The T-C haplotype of MMP-2 may also confer protection against RSA. An elevated serum MMP-2 activity in RSA patients indicates that MMP-2 may serve as potential biomarker.
BACKGROUND:Ulcerative colitis (UC) and psoriasis (PS) are both chronic inflammatory disorders that frequently occur together in clinical settings. Nevertheless, the common genetic basis and biological mechanisms underlying this comorbidity remain insufficiently understood. METHODS:We integrated genome-wide association study summary data with UC and PS single-cell transcriptomic data and performed reference-atlas-based spatial mapping using an E16.5 mouse embryonic spatial transcriptomic atlas to comprehensively investigate their shared genetic relationships, polygenic overlap, tissue-specific enrichment, reference-atlas-based anatomical enrichment patterns, disease-relevant cell populations, and potential candidate genes. RESULTS:Our analyses demonstrated a significant common genetic foundation between UC and PS at both the global and local genomic scales, together with marked polygenic sharing. Enrichment and reference-atlas-based analyses suggested that UC- and PS-associated genetic signals converged on immune-, intestinal- and epidermis-related tissue contexts. Integration of the four-component descriptive prioritization framework identified T cells among the prioritized candidate cell types in both diseases, with concordant support from the CELLECT-S-LDSC and CELLECT-MAGMA components. In addition, several candidate genes, including PARK7, C2orf74, PUS10, and TNFSF15, were prioritized, among which PARK7 showed significant case-control differential expression in T-cell subsets in both UC and PS. CONCLUSION:These findings suggest that UC and PS may share genetic and biological features across tissue and cellular contexts. This study provides a hypothesis-generating framework for investigating their comorbidity and highlights candidate genes with potential therapeutic relevance.
BACKGROUND:T-cell exhaustion marked by soluble PD-1 (sPD-1) and soluble TIM-3 (sTIM-3) has been implicated in systemic lupus erythematosus (SLE), yet the cytokine mechanisms driving checkpoint-receptor upregulation, the relationship with complement consumption, and the clinical utility of these markers remain incompletely characterised. METHODS:In a case-control with cross-sectional study of 120 participants (40 active SLE, 40 quiescent SLE, 40 healthy controls), serum sPD-1, sTIM-3, IL-6, ferritin, complement proteins (C3, C4, C1q), anti-dsDNA, CRP, ESR, and urinary protein-to-creatinine ratio (UPCR) were measured. A 12-parameter Spearman correlation matrix, principal component analysis (PCA) of 10 standardised biomarkers, ROC curve analysis with bootstrap 95% CIs and DeLong pairwise comparisons, lupus-nephritis (LN) subgroup analysis, and four pre-specified novel analyses were performed: (i) formal bootstrap mediation analysis of the IL-6 → sPD-1/sTIM-3 → SLEDAI-2K pathway; (ii) the sTIM-3/sPD-1 imbalance ratio; (iii) an Exhaustion-to-Complement Index (ECI); and (iv) multivariable logistic regression for LN prediction. The SLE Immune Exhaustion Index (SIEI) was evaluated by ROC analysis. RESULTS:Four primary biomarkers were significantly elevated in active versus quiescent SLE and healthy controls (Kruskal-Wallis H 87.2-99.0; all p < 0.001), with strong positive correlations with SLEDAI-2K (rho = 0.647-0.747). PCA identified a single dominant axis (PC1 = 78.9% variance) driven by exhaustion and inflammatory markers opposing complement proteins. Individual ROC AUCs were: sPD-1 0.932, sTIM-3 0.966, IL-6 0.944, and ferritin 0.953; the SIEI achieved 0.974, significantly exceeding sPD-1 alone (p = 0.002) but not the other individual markers. Bootstrap mediation analysis confirmed that sPD-1 and sTIM-3 each mediated approximately one-third of the IL-6 effect on SLEDAI-2K (indirect effects 0.276 and 0.303; bootstrap 95% CI excluding zero; Sobel p < 0.001). The ECI correlated strongly with SLEDAI-2K (rho = 0.86, p < 0.001; within-cohort AUC = 0.985). The UPCR plus sPD-1 plus IL-6 model significantly improved LN prediction over UPCR alone (AUC 0.869 vs 0.699; bootstrap p = 0.020), with sPD-1 carrying the dominant predictive contribution. CONCLUSIONS:Serum sPD-1 and sTIM-3 are closely associated with the IL-6-related, complement-consuming inflammatory network of SLE, in a pattern consistent with but not proving a mechanistic link. The SIEI is the first named, weighted composite exhaustion score in SLE, with within-cohort discrimination that requires prospective external validation. These findings support T-cell exhaustion as a serologically accessible disease axis with direct implications for disease monitoring and lupus-nephritis risk stratification.
BACKGROUND:Single Antigen Bead (SAB) assays are widely used for anti-HLA antibodies detection and virtual crossmatch. Their interpretation assumes that omission of specific HLA alleles can be adequately compensated through representation of shared epitopes on related alleles included within the panel. METHODS:This study retrospectively examined 535 Indian donor-recipient pairs to pinpoint HLA alleles missing from two commercial SAB panels. We analyzed the antibody-verified eplet repertoires of unrepresented alleles using HLAMatchmaker and the HLA Epitope Registry and evaluated the extent to which these repertoires were represented through surrogate alleles included within the SAB panels. RESULTS:At least one unrepresented allele was identified in 35.8% of cases. A total of 77 unique alleles were absent across both panels, including 32 missing alleles from both. Approximately 70% of unrepresented alleles carried antibody-verified eplets, and over 80% demonstrated high or intermediate exposition. Although many antibody-verified eplets were represented through related alleles contained within the SAB panels, the extent of surrogate structural representation varied across recurrent donor alleles. CONCLUSION:Incomplete allele representation in SAB panels may limit the completeness of surrogate epitope-level representation associated with recurrent donor alleles, even when individual antibody-verified eplets remain represented through related alleles. These findings highlight a structural limitation in current SAB design and support incorporation of epitope-level analysis to refine immunological risk assessment. In this study, the term 'SAB GAP' refers to the potential disconnect between allele level representation and the completeness of surrogate structural representation of antibody-verified eplet repertoires within commercial SAB panels.
BACKGROUND:Alopecia areata (AA) is a multifactorial disorder with immune dysregulation and genetic susceptibility, affecting 0.5-2% globally. OBJECTIVE:This study investigated angiotensin converting enzyme (ACE) gene insertion /deletion (I/D) polymorphism and serum ACE activity in Iraqi AA patients and their association with inflammatory cytokines (interleukin [IL]-17) and nutritional markers to understand disease progression. METHODS:This case-control study included 50 AA patients (Male and Female) and 35 healthy controls. ACE gene polymorphism (rs1799752) was analyzed using real-time polymerase chain reaction (qPCR) with high-resolution melting (HRM) analysis. Serum IL-17 levels were determined by enzyme-linked immunosorbent assay (ELISA), and biochemical markers were measured using an automated analyzer. RESULTS:ACE gene polymorphism (rs1799752) showed non-significant genotype distribution between patient and control groups (p > 0.05), though a trend toward DD genotype enrichment was observed in patients. Serum ACE levels were significantly higher in patients versus controls (p < 0.0001) with high diagnostic performance. ACE correlated positively with IL-17 (P < 0.0001) and negatively with vitamin D3 and zinc (P < 0.0001). Female patients had significantly higher ACE levels than males (P < 0.01). CONCLUSIONS:ACE emerges as an immunometabolic hub in AA pathogenesis, integrating inflammation with nutritional deficits, suggesting its potential as a biomarker and therapeutic target.
BACKGROUND:Immune thrombocytopenic purpura (ITP) is the most common autoimmune bleeding disorder in children and poses a serious threat to pediatric health and survival. An imbalance in Th17 and Treg cell differentiation leads to uncontrolled inflammation. METHODS:Peripheral blood mononuclear cells and CD4+ T cells were isolated from 23 ITP patients and 23 healthy controls. Th17 and Treg proportions were quantified by flow cytometry, and serum concentrations of IL-17 A, IL-10, IL-22, IL-23, IL-6, and TNF-α were measured by ELISA. An ITP mouse model was established by splenocyte transfer, and AhR antagonism was evaluated using CH-223191. AhR SUMOylation was assessed by co-immunoprecipitation and western blot, and transcriptional activity was determined by dual-luciferase reporter assay. RESULTS:The Th17/Treg ratio was significantly elevated in ITP patients compared with controls (P < 0.001), accompanied by increased serum IL-17 A, IL-22, IL-23, IL-6, and TNF-α and decreased IL-10 (P < 0.001). AhR mRNA and protein expression were markedly upregulated in ITP CD4+ T cells (P < 0.001). Inhibition of AhR by CH-223191 reduced the Th17 proportion from 3.5% to 2.0% and increased the Treg proportion from 1.2% to 2.8%, normalizing the Th17/Treg ratio (P < 0.001). Consistent results were observed in vivo, with improved platelet counts and restored Th17/Treg balance. Mechanistically, AhR underwent SUMOylation at K63 and K510 by SUMO1, which enhanced AhR protein stability and transcriptional activity; this modification was reversed by SENP1-mediated deSUMOylation. CONCLUSION:Blocking AhR, which is modified by SUMO1 and deSUMOylated by SENP1, alleviates ITP-induced Th17/Treg imbalance through SENP1-mediated deSUMOylation.
