SEARCH · PubMed Health

Results for “MAIT”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

11 recordsLinked to original sources

PubMed2026

Eltrombopag-associated remodeling of the MAIT, MR1+ and γδ T cells in pediatric immune thrombocytopenia.

Pediatric immune thrombocytopenia (ITP) is an autoimmune cytopenia characterized by immune-mediated platelet destruction and impaired thrombopoiesis. Mucosa-associated invariant T (MAIT) cells are innate-like T cells activated by MR1-presented microbial metabolites and inflammatory cytokines, but their role in pediatric ITP and their relationship to eltrombopag therapy remain unclear. We analyzed peripheral blood mononuclear cells from healthy controls (n = 20), untreated pediatric ITP patients (n = 60), and eltrombopag-treated patients (n = 16). MAIT cells were quantified using MR1-5-OP-RU tetramers and surrogate gating (CD3+Vα7.2+CD161+). MAIT subsets, memory phenotype, chemokine receptor expression (CXCR3, CXCR5, CCR6), HLA-DR, intracellular cytokines (IFN-γ, TNF-α, IL-17 A, IL-22), and MR1+CD3- cells were analyzed by flow cytometry. Tetramer-defined MAIT cells were reduced in absolute number in pediatric ITP, including eltrombopag-treated patients, most prominently within the CD8+ subset, whereas their frequency among CD3+ T cells did not differ between untreated and eltrombopag-treated groups. In contrast, CD3+Vα7.2+CD161+ cells increased in untreated ITP and were lower in eltrombopag-treated patients. Untreated ITP patients exhibited reduced frequencies of IFN-γ- and TNF-α-producing MAIT cells, accompanied by increased IL-17-producing cells and TNF-α signal intensity. Conventional αβ T cells were reduced, whereas γδ T cells were increased; eltrombopag-treated patients exhibited γδ T-cell frequencies and cytokine-positive fractions closer to those of healthy controls. MR1+CD3- cells were expanded and displayed reduced HLA-DR expression in untreated ITP, whereas eltrombopag-treated patients showed lower MR1+CD3- frequencies and HLA-DR levels closer to healthy controls. These findings demonstrate coordinated alterations of the MAIT/MR1 axis and unconventional T-cell compartments in pediatric ITP and identify immunophenotypic differences associated with eltrombopag treatment.

Humans↗

PubMed2026

Allelic variation alters expression and antigen presentation of MR1 allomorphs.

The major histocompatibility complex (MHC) class I-related protein 1 (MR1) presents vitamin B-derived metabolites to mucosal-associated invariant T (MAIT) and other T cells. There is limited polymorphism of MR1, the functional impact of which is not understood. We examined the impact of allelic variation of MR1 on the expression, structure and function of the known MR1 allomorphs. The expression and function of MR1∗02, MR1∗03, and MR1∗06 were similar to the canonical MR1∗01. Crystal structures of four MR1 allomorphs show that their polymorphisms do not impact the three-dimensional fold of MR1. Despite the binding of 5-OP-RU to MR1∗05 and its cell surface upregulation, this allomorph was severely impaired in its ability to activate primary MAIT cells. This phenotype was controlled by two (His90Gln and Glu52Gly) of its three polymorphisms, which led to the loss of structurally stabilizing interactions. When cells expressing the MR1 allomorphs were infected with herpes simplex virus type 1 (HSV-1), the nascent expression of all allomorphs was severely impaired, but surface expression of MR1∗04:01 and MR1∗04:02 was relatively less impacted. Hence, MR1 allelic variation alters the expression and function of the MR1∗04 and MR1∗05 allomorphs, with implications for MAIT cell and diverse MR1-reactive T cell immunity.

Humans↗

PubMed2026

Enterococcus faecalis GP1764 induces an early differential gene expression in the intestine on key pathways related to cellular immune response and gut barrier function in chickens.

The aim of the present study was to elucidate the mode of action of Enterococcus faecalis GP1764 in improving performance traits during the starter phase by analyzing genome-wide gene expression and its interaction with microbial populations in the intestine of chickens challenged with an NSP-rich diet. At day 7, microbiota populations from ileal and cecal contents and transcriptomics from jejunal and cecal mucosa were analyzed between Control (Ctrl) and Enterococcus faecalis GP1764 (EntF) groups. Results from microbiota analysis demonstrated that EntF shifted β-diversity indices in ileum (neutral (p= 0.006) and phylogenetic (p= 0.006)) and caecum (phylogenetic (p= 0.017)). Transcriptomics revealed 43 differentially expressed genes for EntF vs. Ctrl in the jejunal mucosa. Of these, MHCY-36 (MHC-I-Related), RAG2 and MUC19-like genes were upregulated in EntF vs. Ctrl, protein-coding genes with immunomodulatory capacities as supported by GSEA and Cytoscape-ClueGo pathway analyses. Results suggest an intestinal immunomodulation induced through presentation of B vitamins metabolites, synthetized by EntF, to an undescribed subset of innate-like unconventional T lymphocytes in chickens, similar to MAIT cells in mammals. These cells could contribute to antibacterial responses and repair of damaged barrier tissue after inflammatory processes. The upregulation of the MUC19-like gene expression observed in the jejunal mucosa can protect gut integrity via the promotion of mucus production by goblet cells. Finally, RAG2, involved in V(D)J coding segments recombination in B- and T-cells may provide a greater recognition of foreign invaders, allowing the animals to efficiently fight against pathogenic infections. Collectively, these results suggest an important role of EntF in promoting the capacity of animals to rapidly act against pathogenic challenges, herein, inducing resilience towards dietary ingredients with anti-nutritional activity that impart moderate inflammation in chickens.

Enterococcus faecalis↗

PubMed2025

A randomized pilot study of HPV16 L2E7E6 fusion protein vaccination site post-treatment for HPV16+ cervical cancer.

OBJECTIVE: Since anti-tumor immunity is enhanced by vaccination of mice adjacent to human papillomavirus type 16 (HPV16+) tumors, we examined whether HPV16 L2E7E6 fusion protein (TA-CIN) vaccination in the thigh of HPV16+ cervical cancer patients would be more immunogenic than their arm. METHODS: HPV16+ cervical cancer (stage IB1-IVA) patients, who had completed standard-of-care treatment within the past year and absent evidence of disease (NED), were enrolled in a pilot study (NCT02405221). Participants were randomized 1:1 to receive three 100 μg TA-CIN monthly intramuscular immunizations either in the arm or thigh and followed for two years for safety (CTCAEv4.0), immune response, and recurrence. RESULTS: Fifteen patients were enrolled (median age 44, range 35-83 years); one patient experienced a non-vaccine-related adverse event after one vaccination and withdrew. Treatment-related adverse events (n = 8) were grade 1, primarily at the injection site, and self-resolved. No recurrence was observed. TA-CIN-specific antibody titers tended to be higher in thigh-vaccinated patients. Bulk TCRseq revealed significant increases in expanded and de novo T cell clones following thigh-vaccination compared with the arm. No correlation with prior treatment modality was observed. E6-, E7-, and L2-specific TCR clones expanded, although L2-specific T cell responses were predominant. One month post-vaccination, scRNAseq revealed significant expansion of MAIT and cytotoxic CD8+ T cells, and both expanded and novel TCR clonotypes were identified in the latter. CONCLUSIONS: Thigh or arm vaccination with TA-CIN was well tolerated, but the former elicited higher CD8 T cell and antibody responses in HPV16+ cervical cancer patients with NED after primary therapy.

Humans↗

PubMed2025

AI-driven multi-omics modeling of myalgic encephalomyelitis/chronic fatigue syndrome.

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic illness with a multifactorial etiology and heterogeneous symptomatology, posing major challenges for diagnosis and treatment. Here we present BioMapAI, a supervised deep neural network trained on a 4-year, longitudinal, multi-omics dataset from 249 participants, which integrates gut metagenomics, plasma metabolomics, immune cell profiling, blood laboratory data and detailed clinical symptoms. By simultaneously modeling these diverse data types to predict clinical severity, BioMapAI identifies disease- and symptom-specific biomarkers and classifies ME/CFS in both held-out and independent external cohorts. Using an explainable AI approach, we construct a unique connectivity map spanning the microbiome, immune system and plasma metabolome in health and ME/CFS adjusted for age, gender and additional clinical factors. This map uncovers altered associations between microbial metabolism (for example, short-chain fatty acids, branched-chain amino acids, tryptophan, benzoate), plasma lipids and bile acids, and heightened inflammatory responses in mucosal and inflammatory T cell subsets (MAIT, γδT) secreting IFN-γ and GzA. Overall, BioMapAI provides unprecedented systems-level insights into ME/CFS, refining existing hypotheses and hypothesizing unique mechanisms-specifically, how multi-omics dynamics are associated to the disease's heterogeneous symptoms.

Humans↗

PubMed2025

RELA Haploinsufficiency Manifesting as an Atypical Phenotype of Crohn's Disease.

BACKGROUND: Mutations in RELA, a key component of NF-κB signaling, are associated with dysregulated immune responses and inflammatory disorders. While immunodeficiency phenotypes associated with RELA haploinsufficiency have been reported, gastrointestinal manifestations remain poorly described. This study aimed to characterize the clinical, genomic, and immunological features of a patient presenting with an atypical Crohn's-like phenotype driven by RELA haploinsufficiency. METHODS: Whole-exome sequencing was performed, and results were confirmed by Sanger sequencing. Protein modeling, Western blotting, immunofluorescence, and nuclear extract-based NF-κB activation assays were conducted to assess the functional impact of the identified variant. Immune profiling was performed using mass cytometry time of flight (CyTOF) and single-cell RNA sequencing (scRNA-seq) and compared to controls. RESULTS: We studied a 17-year-old male diagnosed with pan-enteric Crohn's disease (CD), perianal fistulas, chronic mucocutaneous candidiasis, and chronic lymphopenia. Sequencing identified a heterozygous missense variant in RELA (c.587T>C, p.V196A) that potentially impairs RelA (p65) protein stability, confirmed by reduced activity and diminished protein expression. CyTOF analysis revealed decreased circulating T regulatory cells (Tregs), absence of mucosal Tregs, high apoptotic rates, and elevated IFN-γ induced levels, while scRNA-seq demonstrated a robust type I/II interferon signature in multiple immune subsets. Dysregulated mucosal-associated invariant T (MAIT) and cytotoxic CD4+ T cells exhibited upregulation of IL23R and ADAM12, further linking RELA dysfunction to enhanced pro-inflammatory T cell response and tissue inflammation. CONCLUSION: This study links RELA haploinsufficiency with CD-like features, Th1/Th17 polarization, and interferon-driven inflammation, emphasizing the importance of genetic evaluation in patients with atypical or refractory IBD.

Humans↗

PubMed2026

Spatial niche remodeling of senescent liver-resident immune cells and its role in chronic liver diseases.

The liver serves the triple functions of metabolism, detoxification, and immune surveillance. Its unique immune microenvironment is shaped by continuous exposure to gut-derived antigens, pathogen-associated molecular patterns (PAMPs), and metabolites arriving via the portal vein, necessitating a delicate equilibrium between immune tolerance and effector activation. This equilibrium relies on the coordinated activities of diverse liver-resident immune cell populations-including Kupffer cells (KCs), liver sinusoidal endothelial cells (LSECs), hepatic stellate cells (HSCs), dendritic cells (DCs), tissue-resident memory T cells (TRM), innate-like T cells, including mucosal-associated invariant T (MAIT) cells, natural killer T (NKT) cells, and γδ T cells, innate lymphoid cells (ILCs, encompassing conventional NK cells and helper ILC subsets), and neutrophils. With advancing age and chronic injury, these resident immune cell populations undergo profound senescence-associated phenotypic reprogramming that is spatially organized along the portal-to-central axis of the hepatic lobule. Key mechanisms include: telomere dysfunction and DNA damage accumulation driving persistent activation of p53/p21 and p16/Rb pathways; mitochondrial dysfunction with mitochondrial DNA (mtDNA) leakage fueling the senescence-associated secretory phenotype (SASP) via the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway; epigenetic age acceleration, including genome-wide H3K27me3 heterochromatinization; and metabolic reprogramming toward glycolysis and lipid accumulation. This review proposes a "spatial niche remodeling" framework to integrate these cell-intrinsic senescence programs with their lobular context, intercellular communication network rewiring, and pathogenic roles across the spectrum of chronic liver disease-from steatosis through steatohepatitis, fibrosis, cirrhosis, to hepatocellular carcinoma. We critically evaluate emerging senotherapeutic strategies targeting specific liver-resident immune cell subsets, discuss the barriers to clinical translation, and identify priority areas for future investigation, including the application of spatial multi-omics, humanized models, and epigenetic clock-guided clinical trials.

Kupffer cells↗

PubMed2025

The risk of a second primary cancer in PTEN Hamartoma Tumor Syndrome (PHTS).

PURPOSE: Patients with PTEN Hamartoma Tumor Syndrome (PHTS) have high hereditary cancer risks for breast, endometrial, and thyroid cancer. Patients develop multiple primary cancers, but these risks remain uncertain. We aimed to provide the second primary cancer risk. METHODS: This European cohort study assessed second primary cancer risks with Kaplan-Meier analyses using data from medical files, registries and/or patient questionnaires. RESULTS: Overall, 279 adult PHTS patients with (a history of) cancer were included (80% female). Among females, 106 (54%) developed a PHTS-related second primary cancer after a PHTS-related first primary cancer, whereas 10 (29%) males developed a PHTS-related second primary cancer after a PHTS-related first primary cancer. The 5- and 10-year PHTS-related second primary cancer risks were 24.5% (95% CI = 18.1-32.5) and 45.7% (95% CI = 36.9-55.4) in females and 14.5% (95% CI = 5.7-34.1) and 19.8% (95% CI = 8.6-41.9) in males, respectively. Furthermore, 5- and 10-year risks for a second primary breast cancer after a first primary breast cancer were 23.3% (95% CI = 14.9-35.2) and 45.6% (95% CI = 33.0-60.2) in females, respectively. CONCLUSION: This study demonstrated that PHTS patients have high second primary cancer risks, which is driven by breast cancer in females. Hence, identifying patients with PHTS before or at first primary cancer diagnosis is essential to enable potential early detection or prevention of a second primary cancer through surveillance or risk-reducing surgery.

Humans↗

PubMed2026

CONCR lncRNA organizes a 3'-end structural domain that engages DDX11 for DNA replication and sister chromatid cohesion.

CONCR (DDX11-AS1) is a long noncoding RNA (lncRNA) necessary for the establishment of sister chromatid cohesion. Despite its activity, whether it contains structural elements essential for its function remains unknown. We determined CONCR structural organization and its functional relevance by integrating selective 2'-hydroxyl acylation analyzed by primer extension and mutational profiling (SHAPE-MaP), atomic force microscopy (AFM), evolutionary analyses, cryo-electron microscopy (cryo-EM), and cellular genetic studies. We found that CONCR molecular topology is modular, with highly structured domains connected by flexible linkers. A large 3'-end domain is responsible for binding to DDX11 helicase, can trigger DDX11 ATPase activity, and is essential for proper DNA replication and sister chromatid cohesion. This 3' end comprises two helical arms connecting two multiway junctions with structural motifs conserved among all primate groups and required for DDX11 binding and sister chromatid cohesion. Our results highlight the critical role of RNA structure in CONCR function, with a highly structured 3'-end domain acting as a loading and activation platform for DDX11 helicase.

DEAD-box RNA Helicases↗

PubMed2025

Peri-mitochondrial actin filaments inhibit Parkin assembly by disrupting ER-mitochondria contacts.

Mitochondrial damage represents a dramatic change in cellular homeostasis, necessitating metabolic adaptation and clearance of the damaged organelle. One rapid response to mitochondrial damage is peri-mitochondrial actin polymerization within 2 min, which we term ADA (Acute Damage-induced Actin). ADA is vital for a metabolic shift from oxidative phosphorylation to glycolysis upon mitochondrial dysfunction. In the current study, we investigated the effect of ADA on Pink1/Parkin mediated mitochondrial quality control. We show that inhibition of proteins involved in the ADA pathway significantly accelerates Parkin recruitment onto depolarized mitochondria. Addressing the mechanism by which ADA resists Parkin recruitment onto depolarized mitochondria, we found that ADA disrupts ER-mitochondria contacts in an Arp2/3 complex-dependent manner. Interestingly, overexpression of ER-mitochondria tethers overrides the effect of ADA, allowing rapid recruitment of not only Parkin but also LC3 after mitochondrial depolarization. During chronic mitochondrial dysfunction, Parkin and LC3 recruitment are completely blocked, which is reversed rapidly by inhibiting ADA. Taken together we show that ADA acts as a protective mechanism, delaying mitophagy following acute damage, and blocking mitophagy during chronic mitochondrial damage.

Ubiquitin-Protein Ligases↗

PubMed2026

Microbial decomposer diversity and metabolic function during the decomposition of brine shrimp carcasses in a saline lake.

BACKGROUND: Decomposition of brine shrimp carcasses has a crucial role in carbon cycling of saline lakes, yet the microbial dynamics remain poorly understood. RESULTS: Here we integrated metagenomics, metatranscriptomics, culturomics, metabolomics, and microcosm experiments to investigate microbial community succession and function during brine shrimp (Artemia sp.) carcass decomposition in Barkol Lake, a hypersaline lake in China. A total of 149 metagenome-assembled genomes (MAGs) and 77 pure culture genomes were recovered across 33 phyla, with 72.12% genomes representing species-level novel lineages. Our results reveal diverse bacterial and archaeal taxa, including novel lineages from CG03, T1Sed10-126 and rare archaeal taxa (Asgardarchaeota, Thermoplasmatota, Nanoarchaeota, and Halobacteriota), involved in degradation of biomacromolecules-proteins, carbohydrates, lipids, and nucleic acids-via extracellular hydrolysis, nutrient transport, and intracellular catabolism. These taxa exhibit substrate preferences, rapidly responding to the breakdown of polysaccharides and proteins, followed by lipids and nucleic acids. Hydrolyzed oligomers are further oxidized by various microbes through fermentation, sulfate reduction, and methanogenesis via metabolic handoffs. Additionally, viral auxiliary metabolic genes (AMGs) further enhance microbial host functions, contributing to key ecological processes such as carbon cycling and stress response. A temporally structured microbial decomposer network (MDN) was observed, driving mineralization cascades from fermentation to sulfate reduction and methanogenesis. CONCLUSIONS: This study reveals microbial metabolic handoffs and virus-mediated modulation as critical mechanisms for organic matter turnover, expanding the known diversity and function of decomposers in saline ecosystems. Our findings offer new insights into biogeochemical processes in saline lakes and highlight a synergistic microbial decomposer network involving bacteria, archaea, and viruses that collectively drive nutrient cycling during brine shrimp carcass decomposition. Video Abstract.

Animals↗