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At least 19 recordsLinked to original sources

Maternal and Fetal HLA Heterozygosity in Preeclampsia: Insights From a Large Multi-Ancestry Pregnancy Cohort.

Preeclampsia (PE) is a leading cause of maternal and neonatal morbidity, with immune dysregulation at the maternal-fetal interface central to its pathogenesis. The highly polymorphic HLA region mediates maternal immune tolerance of the semi-allogeneic fetus, yet the contribution of HLA diversity to PE risk remains poorly defined. Whether the HLA heterozygote advantage observed in other immune disorders is relevant to PE has not been systematically evaluated. Using data from the multi-ancestry TOPMed Boston-Colombia Collaborative for Adverse Pregnancy Outcomes (n = 12,790; 4770 PE, 8020 controls; 10,808 maternal, 1982 fetal, including 1848 pairs), we evaluated associations between heterozygosity across eight classical HLA loci and PE and four sub-phenotypes, adjusting for genetic ancestry. HLA heterozygosity was common across most loci (> 80%). No individual maternal HLA locus was associated with overall PE; however, heterozygosity across Class I loci showed a protective effect in preterm PE (OR = 0.81, 95% CI: 0.68-0.97), with a similar pattern for HLA-A heterozygosity (OR = 0.78, 95% CI: 0.64-0.97). In contrast, fetal heterozygosity at HLA-DQB1 was nominally associated with increased risk of PE (OR = 1.36, 95% CI: 1.03-1.80) and preterm PE (OR = 1.73, 95% CI: 1.13-2.74). No individual maternal or fetal HLA alleles were associated with PE. Maternal-fetal mismatch analysis demonstrated locus-specific associations with preterm PE, including increased risk with HLA-DQA1 mismatch and reduced risk with HLA-C mismatch. These findings highlight distinct maternal and fetal immunogenetic contributions to PE risk and underscore the importance of considering HLA diversity-rather than individual alleles alone-in studies of PE aetiology.

Humans

Human Genome REWRITE for Off-the-Shelf Stem Cells Reveals an "Epigenetic Ghost".

Human leukocyte antigen (HLA) polymorphism hinders off-the-shelf cell therapies. We developed REWRITE, a modular platform for iterative, scar-minimized genome writing of synthetic constructs >100 kb in human pluripotent stem cells (hPSCs). Using REWRITE, we deleted 105-209 kb of the HLA locus and installed synthetic 24 kb or 100 kb HLA haplotypes, and a 62 kb antigen-processing locus. This uncovered a persistent, heritable "epigenetic ghost" - an active state lingering despite genetic removal - whose resolution to a silenced default state is driven by native intergenic DNA. These loci restored inducible expression in key lineages, sparing cells from NK-mediated killing and establishing HLA-matched T-cell tolerance, enabling off-the-shelf cell therapies. REWRITE facilitates extensible programming of multigenic functions in allogeneic human cells - from immune design to genome architecture discovery.

Journal Article

Investigations of HLA-F and HLA-G 3'UTR Polymorphisms in Preeclampsia and Fetal Growth Restriction Indicate a Possible Role of HLA-F-HLA-G Haplotypes and Diplotypes.

HLA-F and HLA-G may be involved in the pathogeneses of preeclampsia and fetal growth restriction (FGR). However, the functions of HLA-F and HLA-G in placental dysfunction remain unclear. The aim was to investigate differences in the prevalence of specific HLA-F and HLA-G gene allelic polymorphisms, genotypes, haplotypes, and diplotypes between controls and cases with preeclampsia or FGR. In total, blood samples from 365 pregnant females (controls, n = 192; preeclampsia, n = 164; FGR, n = 19) in their second and third trimester, and corresponding cordial blood samples (reflecting newborns, n = 160) were obtained after delivery. Genomic DNA was sequenced with a focus on the specific gene polymorphisms in the HLA-F gene locus, especially the single nucleotide polymorphisms (SNPs) rs1362126 (G/A), rs2523405 (T/G) and rs2523393 (A/G), as well as the rs371194629 (14-bp ins/del) in the 3'UTR of HLA-G. Haplotype and diplotype distributions were obtained using PHASE v2.1, and linkage disequilibrium analyses were performed. SNPs in the HLA-F gene locus and the 3'UTR of HLA-G were not associated with the risk of preeclampsia or FGR. The SNPs did not correlate with fetal-placental weight ratio, deviation of birth weight at gestational age, and placental weight. However, a trend towards an absence of certain HLA-F-HLA-G extended diplotypes in preeclampsia was observed. The current study does not support associations of the investigated HLA-F SNPs with preeclampsia or FGR. However, further studies are needed to evaluate the possible role of certain fetal HLA-F-HLA-G extended haplotypes and diplotypes in preeclampsia.

Humans

Identification of Genetic Variations in HLA Region for Kidney Functions.

HLA allelic polymorphisms are associated with a variety of kidney-related traits in different populations. Although Taiwanese-specific genetic variants associated with kidney function have been reported, the role of HLA alleles is unclear. In this study, the association between eGFR and genetic variations in the HLA region was explored in a cohort of 59,448 Taiwanese subjects. A total of 448 genetic variations in the HLA region are significantly associated with eGFR. HLA-C*03 is associated with decreased eGFR, while HLA-DQA1*03, HLA-DQB1*03:03 and HLA-DQB1*03:03:02 demonstrated protective effects. Moreover, amino acid changes on HLA-C and HLA-DRB1 are significantly associated with eGFR. Finally, the eGFR-associated single nucleotide variations (SNVs) and insertions and deletions (indels) are enriched in the HLA-DQB1 gene. After conditional analysis, we identified two independent signals, including rs2853941, rs3830060. In summary, this study highlights the role of HLA-C, HLA-DQA1, HLA-DQB1 and HLA-DRB1 variations in kidney function in the Taiwan Han Chinese population.

Adult

Targeting peptide antigens using a multiallelic MHC I-binding system.

Identifying highly specific T cell receptors (TCRs) or antibodies against epitopic peptides presented by class I major histocompatibility complex (MHC I) proteins remains a bottleneck in the development of targeted therapeutics. Here, we introduce targeted recognition of antigen-MHC complex reporter for MHC I (TRACeR-I), a generalizable platform for targeting peptides on polymorphic HLA-A*, HLA-B* and HLA-C* allotypes while overcoming the cross-reactivity challenges of TCRs. Our TRACeR-MHC I co-crystal structure reveals a unique antigen recognition mechanism, with TRACeR forming extensive contacts across the entire peptide length to confer single-residue specificity at the accessible positions. We demonstrate rapid screening of TRACeR-I against a panel of disease-relevant HLAs with peptides derived from human viruses (human immunodeficiency virus, Epstein-Barr virus and severe acute respiratory syndrome coronavirus 2), and oncoproteins (Kirsten rat sarcoma virus, paired-like homeobox 2b and New York esophageal squamous cell carcinoma 1). TRACeR-based bispecific T cell engagers and chimeric antigen receptor T cells exhibit on-target killing of tumor cells with high efficacy in the low nanomolar range. Our platform empowers the development of broadly applicable MHC I-targeting molecules for research, diagnostic and therapeutic applications.

Humans

HLA-B Serine 116 Confers Protection Against Severe COVID-19 in a Cohort From Rio de Janeiro, Brazil.

COVID-19 is a respiratory disease caused by SARS-CoV-2, in which severe outcomes are primarily driven by an exacerbated immune response. The HLA region has been extensively investigated in COVID-19 due to its central role in the immune response, although genetic associations vary across populations. Here, the association of HLA genetic variability with COVID-19 severe respiratory outcomes was investigated in an admixed population from Rio de Janeiro, Brazil. Results of a comparative study between mild and severe COVID-19 cases involving 306 individuals have suggested risk associations with severe COVID-19 for the HLA-DPB1*13:01 allele (OR = 3.42, 95% CI = 1.05-11.16, p = 0.041) and the HLA-B*39 allele group (OR = 3.26, 95% CI = 1.16-9.13, p = 0.024), although statistical significance was lost after FDR adjustment for multiple comparisons (adjusted p > 0.05). Amino acid analyses showed that a serine at position 116 of HLA-B conferred protection against severe COVID-19 (OR = 0.4774, 95% CI = 0.28-0.81, p = 0.006, adjusted p = 0.031). In silico analysis using the NetMHCpan tool predicted that this residue, located in the HLA-B peptide-binding groove, has enhanced binding affinity to immunodominant SARS-CoV-2 epitopes, suggesting a functional mechanism underlying the observed protection. The association of single nucleotide variants at the HLA region was also investigated, and no statistically significant association was found. Results obtained in the present study underscore the importance of HLA in COVID-19 severity, likely mediated by its influence on viral peptide presentation, and advance our understanding of the genetic underpinnings of severe disease in admixed populations.

Humans

Chimeric vaccine based on Iraqi HLA alleles against a predominant local Escherichia coli phylogroup.

INTRODUCTION: Escherichia coli remains amongst the most globally important pathogens implicated in severe clinical manifestations. The progressive rise in multidrug-resistant strains highlights the urgent need for new vaccines. Therefore, this study was designed to develop a new multi-epitope vaccine containing the most conserved epitopes across E. coli pathotypes. Consequently, the study aimed to investigate the immunoadjuvant role of faecal microbiota transplantation in enhancing vaccine efficacy. METHODS: Eighteen of the most conserved B-cell and T-cell epitopes of FimH, LptD, and BamA proteins were selected and included in a single construct. During the epitope selection process, HLA alleles predominant in the Iraqi population, as reported in previous studies, were used as criteria for selecting T-cell epitopes. The chimeric protein was expressed in BL21 E. coli and purified using affinity chromatography. Vaccine cross-protective immunity and protection were tested in in vivo experiments. Different formulations were used in the experimental evaluation: three doses of 100 μg of purified chimeric protein, injected intraperitoneally alone or encapsulated in PLGA nanoparticles, after faecal microbiota transplantation with and without gut microbiota modulation mediated by a cocktail of antibiotics. IgG1, IL-4, INF-γ, and NLRP3 levels were measured at 30 and 75 days after the first immunisation dose. Immunised mice were challenged with the local B2 UPEC phylogroup, and protection efficacy was considered 48 h later. Finally, the histological effects of the different chimeric protein formulations on the liver were assessed. RESULTS: All vaccine formulations except those after faecal microbiota transplantation without gut microbiota modulation induce significant increases in IgG1, IL-4, and INF-γ levels at different times. Only vaccination after faecal microbiota transplantation with gut microbiota modulation elicited robust NLRP3 levels at 30 and 75 days after, and this was linked to the highest reduction in bladder bacterial load by 813-fold compared to the other formulations, as well as the mildest effect on liver histological changes. DISCUSSION: These results demonstrated that the chimeric vaccine provides preliminary protection against a local B2 UPEC isolate. Furthermore, modulating gut microbiota via faecal transplantation markedly enhances the immunogenicity and protective efficacy of vaccination, suggesting its adjuvanticity.

Animals

HLA-DRB1*14 is associated with lower odds of symptomatic SARS-CoV-2 infection in Mexican individuals.

Mexico has been one of the countries most affected by the COVID-19 pandemic. Several factors can influence the susceptibility to SARS-CoV-2 infection, particularly highly polymorphic genes in the HLA system. Therefore, this pilot study analyzed the association between HLA-DRB1 genetic polymorphisms and the susceptibility and/or resistance to symptomatic SARS-CoV-2 infection in a population from the Metropolitan Area of the Valley of Mexico. Individuals with a confirmed SARS-CoV-2 infection were recruited (n = 90), as well as a seronegative control group without reported symptomatic infection (n = 60). The HLA-DRB1 locus was typed using NGS. We found a significant increase in the frequency of the HLA-DRB1*14 allele in the control group (OR = 0.37; 95% CI: 0.18-0.72; p = 0.003; pc = 0.03). These data suggest that HLA-DRB1*14, a prevalent allele in the Mexican population, is associated with a reduced risk of symptomatic SARS-CoV-2 infection in this cohort.

Humans

Genetic Variants at the NAT2 and HLA-DOA are Associated With Anti-Tuberculosis Drug-Induced Liver Injury Susceptibility and Clinical Manifestations in Western Chinese Populations.

BACKGROUND: Anti-tuberculosis drug-induced liver injury (ATDILI) is one of the most prevalent and serious adverse reactions during anti-tuberculosis treatment and can potentially lead to liver failure or mortality. This study aims to investigate whether genetic variants in the N-acetyltransferase 2 gene (NAT2) and the HLA-DOA gene (HLA-DOA) are associated with ATDILI susceptibility and clinical manifestations in a Western Chinese population. METHODS: A total of 1358 participants with active tuberculosis were enrolled and genotyped for four NAT2 polymorphisms and five HLA-DOA loci. Associations between candidate genetic variants and ATDILI were evaluated using logistic regression analyses, with multiple comparisons adjusted by Bonferroni correction. RESULTS: The overall incidence of ATDILI was 28.4% (385/1358) in this cohort. Under a recessive model, NAT2 rs1799930 was found to increase the risk of ATDILI (odds ratio [OR] = 1.88, 95% confidence interval [CI]: 1.20-2.95, p = 0.006), which remained significant after Bonferroni correction (adjusted p = 0.048). Meanwhile, while HLA-DOA rs1367731 (OR = 0.41, 95% CI: 0.18-0.93, p = 0.033), rs6913008 (OR = 0.39, 95% CI: 0.17-0.89, p = 0.024), and rs9276975 (OR = 0.47, 95% CI: 0.23-0.98, p = 0.045) demonstrated a promising protective genomic characteristic that may mitigate the development of ATDILI. However, none of the reported HLA-DOA associations remained statistically significant after applying Bonferroni corrections. Regarding clinical manifestations, NAT2 rs1799930 and rs1799931 have been linked to poor ATDILI clinical presentations, whereas certain HLA-DOA variants (rs1367731, rs6913008, and rs9276975) were possibly linked to milder ATDILI severity. CONCLUSION: Our findings preliminarily suggest that the NAT2 and HLA-DOA genetic variants may play a role in ATDILI susceptibility and clinical outcomes. NAT2 rs1799930 represents a potential genetic risk marker, while HLA-DOA variants may serve as protective factors warranting further validation. These findings may contribute to the precision management of ATDILI and the prevention of anti-TB drug-associated liver injury.

Adult

Asymptomatic SARS-CoV-2 Infection: Association Involving the HLA-B*15 Allele Group in Brazilian Individuals.

The aim of this study was to investigate the influence of HLA-A, -B and -C polymorphisms on the clinical course of SARS-CoV-2 infection and on the progression of COVID-19 in a population from southeastern Brazil. This study included 478 unvaccinated individuals. Of these, 369 were hospitalised with critical/severe (n&#x2009;=&#x2009;309) or moderate/mild (n&#x2009;=&#x2009;60) symptoms, and 109 were asymptomatic. The control group consisted of 150 volunteer bone marrow donors, recruited in the pre-pandemic period. The HLA-B*15 allele group (adjusted p value&#x2009;<&#x2009;0.001) was associated with a protective factor against symptomatic infection. Investigating the effects of the distribution of HLA alleles on susceptibility and resistance to SARS-CoV-2 may provide a better understanding of the clinical course of infection in different geographical regions.

Humans

HLA and non-HLA genetic analyses reveal suggestive variants associated with statin-induced liver injury.

BACKGROUND: Statins are widely prescribed for cardiovascular risk reduction and are generally well tolerated. However, they can cause drug-induced liver injury (DILI), and the genetic factors contributing to statin-DILI remain poorly understood. METHODS: HLA association and genome-wide association (GWAS) studies were conducted to identify genetic variants associated with statin-DILI. High-confidence cases (n=71) were identified from the Drug-Induced Liver Injury Network (DILIN) and compared with statin-exposed controls without liver injury (n=551) from the Indiana Biobank. Association testing was performed across ancestries and within ancestry, adjusting for age, sex, and three principal components of genotypes. Top variants were further evaluated in non-statin DILI cases and unexposed controls. In addition, we investigated the frequency of candidate variants among a comprehensive list of pharmacogenetic variants related to statins. RESULTS: HLA-DQA1*03:01 was significantly associated with increased risk of statin-DILI (OR=3.49, 95% CI 2.21-5.51, p-value=1.27&#xd7;10-7), with enrichment observed across multiple ancestry groups, particularly non-Hispanic Black and Hispanic individuals. From the GWAS, three loci showed suggestive associations (p-value <5&#xd7;10-06) with statin-DILI, including rs35197737 in RGS1 (OR=5.03, 95% CI 1.11-3.66, p=1.14&#xd7;10-7), rs75629598 in FRMD4A (OR=4.4, 95% CI=2.33-8.12, p=3.97&#xd7;10-6), and rs7658630 in the intergenic region on chromosome 4 (OR=4.86, 95% CI 2.66-8.85, p=2.68&#xd7;10-7). No pharmacogenetic variants revealed statistical significance. CONCLUSION: We identified HLA and non-HLA genetic variants associated with statin DILI. Future studies with larger sample sizes should confirm these observations.

Humans