HLA-DRB1 Alleles Research Articles

Shared lung and joint T cell repertoire in early rheumatoid arthritis driven by cigarette smoking

ObjectivesSmoking has been associated with an increased risk of developing rheumatoid arthritis (RA) in individuals carrying shared epitope (SE) HLA-DRB1 alleles. Yet, little is known about the regional and systemic...

HLA-DRB1*01 predicts treatment outcome in juvenile idiopathic arthritis: A retrospective-prospective cohort study.

Juvenile idiopathic arthritis (JIA) is the most common chronic inflammatory autoimmune disease in childhood, significantly contributing to both short- and long-term disability. While certain human leukocyte antigen (HLA) class II alleles are known to be associated with specific subgroups of JIA, emerging evidence suggests a strong correlation between these alleles and treatment response. This study involved 143 JIA patients diagnosed according to International League of Associations for Rheumatology criteria. Each patient underwent HLA class II typing, including HLA-B27, as well as tests for rheumatoid factor (RF) and antinuclear antibodies (ANA). Comprehensive rheumatological assessments were conducted at diagnosis, with follow-ups at three and six months post-onset. After six months of methotrexate (MTX) treatment, patients were categorized as responders or non-responders. Responders achieved clinically inactive disease based on the American College of Rheumatology Provisional Criteria for Defining Clinical Inactive Disease and Clinical Remission. Non-responders, who did not reach clinically inactive disease after six months of treatment, required the addition of another non-biological disease-modifying antirheumatic drug (DMARD) or a biological DMARD. Our analysis revealed that the HLA-DRB1*01 allele is a significant prognostic marker for therapeutic response, predicting therapeutic resistance (P=0.01). The most prevalent HLA-DRB1 alleles in the treatment-resistant group were HLA-DRB1*08:11 (11.3%), HLA-DRB1*01:01 (8.5%), HLA-DRB1*01:13, HLA-DRB1*04:11 (7%), HLA-DRB1*08:13, and HLA-DRB1*08:15 (4.2%). These findings highlight the critical role of HLA class II alleles in pediatric rheumatology, particularly in relation to treatment response and disease prognosis. In the era of personalized medicine, understanding the genetic contributions to treatment response and outcomes in JIA patients is essential. A key limitation of this study was the lack of comparison of treatment responses across different JIA subtypes. Future studies should prioritize evaluating MTX efficacy within specific JIA subgroups to enable a more tailored understanding of its effectiveness.

Genomic and Serological Rheumatoid Arthritis Biomarkers, MUC5B Promoter Variant, and Interstitial Lung Abnormalities.

Rheumatoid arthritis (RA) has been implicated in interstitial lung disease (ILD) as majority of studies have been comprised of patients with known RA. However, it remains unclear whether an underlying risk for RA in combination with genetic risk for pulmonary fibrosis is associated with radiological markers of early lung injury and fibrosis in broader population samples. Determine whether genetic and serological biomarkers of RA risk in combination with the MUC5B (rs35705950) risk allele (T) are associated with interstitial lung abnormalities (ILA) on computed tomography (CT) scans. Associations of RA-risk HLA-DRB1 alleles (*04:01, *04:08, *04:05, *04:04, *10:01) and serum RA autoantibodies with ILA in the Multi-Ethnic Study of Atherosclerosis (MESA, n=4,018) and COPDGene (n=5,963) cohorts were modeled using logistic regression and adjusted for age, sex, self-reported race and ethnicity, smoking history, body mass index, and principal components of genetic ancestry. The prevalence of an RA risk HLA-DRB1 allele was 16.5% and 21.9% in MESA and COPDGene, respectively. ILA was present in 3.9% and 11% in MESA and COPDGene, respectively. An RA risk HLA-DRB1 allele was not significantly associated with ILA in MESA and COPDGene. In MESA, higher serum levels of IgA rheumatoid factor (RF) and anti-cyclic citrullinated peptide were associated with an odds ratio (OR) for ILA of 1.20 (95% CI 1.07-1.35) and 1.19 (95% CI 1.04-1.37), respectively. Among smokers without baseline ILA, per doubling of IgM RF was associated with an OR for ILA 10 years later of 1.25 (95% CI 1.08-1.43). Associations were not significantly different by MUC5B risk allele status. RA-related HLA-DRB1 alleles were not associated with ILA, whereas higher serum levels of IgM RF among smokers without baseline ILA were associated with subsequent ILA.

Selective HLA Class II Allele-Restricted Activation of Atabecestat Metabolite-Specific Human T-Cells.

Elevations in hepatic enzymes were detected in several trial patients exposed to the Alzheimer's drug atabecestat, which resulted in termination of the drug development program. Characterization of hepatic T-lymphocyte infiltrates and diaminothiazine (DIAT) metabolite-responsive, human leukocyte antigen (HLA)-DR-restricted, CD4+ T-lymphocytes in the blood of patients confirmed an immune pathogenesis. Patients with immune-mediated liver injury expressed a restricted panel of HLA-DRB1 alleles including HLA-DRB1*12:01, HLA-DRB1*13:02, and HLA-DRB1*15:01. Thus, the objectives of this study were to (i) generate DIAT-responsive T-cell clones from HLA-genotyped drug-naive donors, (ii) characterize pathways of DIAT-specific T-cell activation, and (iii) assess HLA allele restriction of the DIAT-specific T-cell response. Sixteen drug-naive donors expressing the HLA-DR molecules outlined above were recruited, and T-cell clones were generated. Cellular phenotype, function, and HLA-allele restriction were assessed using culture assays. Peptides displayed by HLA class II molecules in the presence and absence of atabecestat were analyzed by mass spectrometry. Several DIAT-responsive CD4+ clones, displaying no reactivity toward the parent drug, were successfully generated from donors expressing HLA-DRB1*12:01, HLA-DRB1*13:02, and HLA-DRB1*15:01 but not from other donors expressing other HLA-DRB1 alleles. T-cell clones were activated following direct binding of DIAT to HLA-DR proteins expressed on the surface of antigen presenting cells. DIAT binding did not alter the HLA-DRB1 peptide binding repertoire, indicative of a binding interaction with the HLA-associated peptide rather than with the HLA protein itself. DIAT-specific T-cell responses displayed HLA-DRB1*12:01, HLA-DRB1*13:02, and HLA-DRB1*15:01 restriction. These data demonstrate that DIAT displays a degree of selectivity toward HLA protein and associated peptides, with expression of certain alleles increasing and that of others decreasing, the likelihood that a drug-specific T-cell response develops.

Elevated serum angiotensin converting enzyme correlates with specific HLA-DRB1 alleles and extrapulmonary manifestations in sarcoidosis

BackgroundGenetics influence the clinical picture in sarcoidosis, a granulomatous heterogeneous disease often accompanied by elevated serum angiotensin converting enzyme (s-ACE). We aimed to investigate if certain HLA-DRB1 alleles correlate with the levels of s-ACE, known as a marker of the granuloma burden. MethodsMedical journals of patients with sarcoidosis from a Swedish clinical registry were retrospectively examined to extract the highest recorded s-ACE value and analysed in relation to patient characteristics including phenotype [Löfgren syndrome (LS)/ non-LS], chest X-ray staging according to Scadding, treatment with immunosuppressants, presence of extrapulmonary manifestations (EPM), HLA-DRB1 alleles and prognosis (resolving vs. non-resolving disease within 2 years). Data were analysed with Fisher's exact test and Bonferroni correction was applied for HLA analyses. ResultsOf 1204 patients included, 40% had s-ACE levels above reference value. In comparison with patients with normal s-ACE, those with elevated levels were more often classified into non-LS (78% vs 59%, p < 0.001), and Scadding stage II (50% vs 38%, p < 0.001) but less often Scadding stage I (33% vs 46%, p < 0.001) and had more often EPM (45% vs 23%, p < 0.001). The patients with HLA-DRB1×04 had more often elevated s-ACE (p < 0.01) while those with HLA-DRB1×03 commonly had normal levels (p < 0.001). ConclusionsIn this retrospective study, HLA alleles associated with s-ACE levels in sarcoidosis patients, which in turn correlated with occurrence of EPM. These findings shed some new light on possible mechanisms behind differences in s-ACE levels.

Frequencies of Human Leukocyte Antigen Alleles in Turkish Children with Kawasaki Disease

Abstract Objective Kawasaki disease (KD) is an acute systemic vasculitis that is one of the major causes of acquired heart disease especially in young children. The pathogenesis of KD is still unclear. The increased incidence of the disease among Japanese children and siblings of affected patients suggests a genetic component to KD susceptibility. Several reports have studied human leukocyte antigen (HLA) polymorphisms in different populations with KD and found various results. In the present study, we aimed to evaluate the association of HLA-A, -B, -C, -DRB1, and -DQB1 allele frequencies in Turkish children with KD. Methods The study was conducted between January 2016 and February 2018. HLA Class I (A, B, and C) and Class II (DRB1 and DQB1) alleles of patients and healthy controls were studied using the low-resolution DNA-based sequence-specific oligonucleotide method. Results Fifty children with KD and 500 healthy controls were included in this study. In the analysis of HLA-A, HLA-B, HLA-C, and HLA-DRB1 alleles, no statistical difference was found in the frequency of alleles between the patients with KD and the control group. However, a significantly lower frequency of the HLA-DQB1*03 allele was observed in the KD group than in the control group (p &lt; 0.001, odds ratio [OR]: 0.29, 95% confidence interval [CI]: 0.15–0.55). When the patients with KD were divided into two subgroups with or without coronary artery lesions (CALs), the frequency of the HLA-DQB1*03 allele was also found lower in the KD group with CALs than the KD group without CALs (p = 0.008, OR: 0.19, 95% CI: 0.05–0.68). Conclusion The study may guide future studies on HLA-DQB1*03 whether it is a protective allele for KD and CALs in Turkish children.

Prevalence of Human Leukocyte Antigen Alleles Polymorphism in North Indian Population

Background Human leukocyte antigens (HLA) are highly polymorphic glycoproteins required for immune response and recognizing self or non-self. Knowing the HLA diversity in a population may be helpful in the selection of organ allocation for transplantation. We aimed to retrospectively analyze the prevalence of HLA, A, B, C, DRB1, and DQA1 alleles frequency in the north Indian population. Materials and Methods HLA antigen allele data were retrospectively analyzed from a transplant cohort of 2259 subjects. HLA-A, B, and DRB1 frequency were determined in 2259, HLA-C in 759 and DQA1 in 751 subjects. Results The most abundant HLA-A antigen alleles were HLA-A*01(25.41%), HLA-A*02 (24.83%), HLA-A*11 (17.53%), HLA-A*24 (10.27%), HLA-A*03 (9.07%). HLA-B antigen alleles were HLA-B*35 (20.54%), HLA-B*15 (15.36%), HLA-B*40 (13.59%), HLA-B*07 (10.14%), HLA-B*44 (7.79). HLA-C antigen alleles were HLA-C*07 (28.06%), HLA-C*04 (20.42%), HLA-C*03 (15.55%), HLA-C*06 (13.04%), HLA-C*12 (5.27%). HLA-DRB1 alleles were HLA-DRB1*07 (21.60%), HLA-DRB1*04 (19.74%), HLA-DRB1*10 (13.15%), HLA-DRB1*03 (10.80%), HLA-DRB1*11 (8.63%). HLA-DQA1 antigen alleles were HLA-DQA1*03 (35.42%), HLA-DQA1*02 (30.89%), HLA-DQA1*05 (21.84%), HLA-DQA1* 06 (10.12%), HLA-DQA1*04 (1.07%). Conclusion The most frequent HLA alleles were HLA-A*01(25.41%), HLA-B*35 (20.54%), HLA-C*07 (28.06%), HLA-DRB1*07(21.60%), HLA-DQA1*03(35.42%) in north Indian population.

Does HLA explain the high incidence of childhood-onset type 1 diabetes in the Canary Islands? The role of Asp57 DQB1 molecules

The Canary Islands inhabitants, a recently admixed population with significant North African genetic influence, has the highest incidence of childhood-onset type 1 diabetes (T1D) in Spain and one of the highest in Europe. HLA accounts for half of the genetic risk of T1D.AimsTo characterize the classical HLA-DRB1 and HLA-DQB1 alleles in children from Gran Canaria with and without T1D.MethodsWe analyzed classic HLA-DRB1 and HLA-DQB1 alleles in childhood-onset T1D patients (n = 309) and control children without T1D (n = 222) from the island of Gran Canaria. We also analyzed the presence or absence of aspartic acid at position 57 in the HLA-DQB1 gene and arginine at position 52 in the HLA-DQA1 gene. Genotyping of classical HLA-DQB1 and HLA-DRB1 alleles was performed at two-digit resolution using Luminex technology. The chi-square test (or Fisher's exact test) and odds ratio (OR) were computed to assess differences in allele and genotype frequencies between patients and controls. Logistic regression analysis was also used.ResultsMean age at diagnosis of T1D was 7.4 ± 3.6 years (46% female). Mean age of the controls was 7.6 ± 1.1 years (55% female). DRB1*03 (OR = 4.2; p = 2.13–13), DRB1*04 (OR = 6.6; p ≤ 2.00–16), DRB1* 07 (OR = 0.37; p = 9.73–06), DRB1*11 (OR = 0.17; p = 6.72–09), DRB1*12, DRB1*13 (OR = 0.38; p = 1.21–05), DRB1*14 (OR = 0.0; p = 0.0024), DRB1*15 (OR = 0.13; p = 7.78–07) and DRB1*16 (OR = 0.21; p = 0.003) exhibited significant differences in frequency between groups. Among the DQB1* alleles, DQB1*02 (OR: 2.3; p = 5.13–06), DQB1*03 (OR = 1.7; p = 1.89–03), DQB1*05 (OR = 0.64; p = 0.027) and DQB1*06 (OR = 0.19; p = 6.25–14) exhibited significant differences. A total of 58% of the studied HLA-DQB1 genes in our control population lacked aspartic acid at position 57.ConclusionsIn this population, the overall distributions of the HLA-DRB1 and HLA-DQB1 alleles are similar to those in other European populations. However, the frequency of the non-Asp-57 HLA-DQB1 molecules is greater than that in other populations with a lower incidence of T1D. Based on genetic, historical and epidemiological data, we propose that a common genetic background might help explain the elevated pediatric T1D incidence in the Canary Islands, North-Africa and middle eastern countries.

HLA class II profile in patients with different stages of cystic echinococcosis according to the WHO ultrasound imaging classification.

The factors involving in the natural history and determinants of different features of human cystic echinococcosis (CE) are not adequately understood. Several host-related factors including the genetic structure of the host and human leukocyte antigens (HLAs) are believed to be involved in the natural history of CE in humans. The present study was conducted to investigate the association between HLA class II genes and active and inactive stages of hepatic cystic echinococcosis. Echinococcus granulosus cyst samples and patient information were collected from the biobank of the Iranian Hydatid Disease Registry from 2019 to 2022. HLA-DRB and HLA-DQB were characterized by PCR method. CE patients were categorized into three active (CE1 and CE2), inactive (CE4 and CE5), and transitional (CE3) stages according to the WHO ultrasound classification of CE. In total, 77 participants including 38 patients (36.8% men and 63.2% women) with different stages of CE as well as 39 healthy individuals (38.5% men and 61.5% women) were included in the study. Findings of the study showed that the frequency of HLA-DRB1*03 was significantly lower in the patients compared to the healthy individuals. The frequencies of HLA-DQB and HLA-DRB alleles were not differed significantly between active, inactive, and transitional stages of E. granulosus cysts. Findings of this study indicate the potential role of this allele in the susceptibility of human to cystic echinococcosis. Further large-scale studies in different endemic countries are required to document the significance of HLA-DQB and HLA-DRB as a host-related factor in the natural history of CE in human.

Association between human leukocyte antigen class II-DR-DQ and narcolepsy: a case control study.

Narcolepsy is a neurologic disorder characterized by irresistible sleep attacks. Although its etiology is unknown, it is strongly associated with genetic variances in the human leukocyte antigen (HLA) complex. We investigated the association of HLA class II-DR-DQ alleles in a sample of patients with narcolepsy-cataplexy (narcolepsy type 1; NT1) and patients with narcolepsy without cataplexy (narcolepsy type 2; NT2) with a control group. Additionally, we compared demographic, clinical, and laboratory characteristics of patients with narcolepsy with or without the DQB1*06:02 allele. This case control study included 21 patients with NT1 (56.8%), 16 patients with NT2 (43.2%), and 100 controls. Sequence-based typing identified HLA-DRB1 alleles, and HLA-DQB1 typing was done using PCR-Sequence-Specific Oligonucleotide. Allele and haplotype frequencies were calculated by direct counting. Nocturnal polysomnography and Multiple Sleep Latency Test were performed in all participants. In the NT1 group, only one allele had a significantly higher frequency than in the NT2 group: DQB1*06:02 (61.9% vs. 18.8%;). Compared to controls, DQB1*06:02 (61.9% vs. 18.0% in controls) and DRB1*15:01(47.6% vs. 8.0%), had higher frequencies in patients with NT1. Multiple analyses showed that patients with NT1 had an increased chance of being HLA-DQB1*06:02 positive. HLA-DRB1*15:01-DQA1*01:02-DQB1*06:02 haplotype is associated with NT1 in our Brazilian patients. PSG was identified in DQB1*06:02 positive subgroup REM sleep latency (REML) ≤ 15 minutes, and all patients had two or more sleep-onset REM periods (SOREMPs) at MSLT. This study showed a strong association between HLA DQB1*06:02 and the haplotype HLA-DRB1*15:01-DQA1*01:02-DQB1*06:02 in patients with NT1. Patients with DQB1*0602 allele showed shorter REMLs at PSG. These results reinforce the suggestion of DQB1 genotyping as relevant to narcolepsy screening.

Model for the Study of Drug Hypersensitivity Based on Bucilamine and the HLA-DRB1*08:02 Allele in Colombian Amerindian Populations

Backgrounds: Allergic diseases and hypersensitivity reactions are common disorders that in turn consist of an extensive genetic component in which the molecules of the Major Histocompatibility Complex (MHC) are included, which have certain alleles associated with the development of hypersensitivity to certain drugs, among which is the allele HLA-DRB1 * 08: 02 as a predisposing factor of hypersensitivity to Bucillamine; this drug is the starting point for the study of the relationship between hypersensitivity reactions to medications and the expression of certain alleles of MHC. Objective: Find the relationship between hypersensitivity to the drug and the expression of the specific allele in Amerindian populations of the Sierra Nevada de Santa Marta and in turn suggest the application of the methodological model proposed in similar studies that seek to relate drug allergies with specific HLA alleles. Methods: A systematic search of information was carried out in the Sience, ScienceDirect, Elsevier and Pubmed databases, the frequencies obtained were tabulated and organized according to their expression to be analyzed with the MEGA7 software. Results: A significant frequency of the HLA-DRB1 * 08: 02 allele was found in the Ijka (61.7%), Arhuaco (41.5%), Kogi (17.9%) and Arsario (15%). Conclusion: A cautious use of Bucillamine and structurally similar drugs it’s recommended in susceptible Amerindian populations, at the same time the application of the proposed model it’s recommended for the study of different drugs that could trigger an allergic reaction based on HLA’s allele expression.

Human leukocyte antigen class II (DRB1 and DQB1) alleles frequencies in patients with bullous pemphigoid, Stevens–Johnson syndrome and toxic epidermal necrolysis in Russian population

BACKGROUND: Bullous pemphigoid is known to be an autoimmune, life-threatening blistering skin disorder characterized by subepidermal blister formation. In bullous pemphigoid activation of B-cell immunity depends on the interaction between T-cell receptors and classic HLA II molecules. Similar interrelation has been revealed in a vast variety of studies on severe allergic reactions such as Stevens-Johnson syndrome and toxic epidermal necrolysis. It was also suggested that Stevens-Johnson syndrome and toxic epidermal necrolysis might be associated both with HLA I and II classes. AIM: To assess the prevalence of HLA-DRB1 and DQB1 alleles at a low and high-resolution levels in patients with bullous pemphigoid and Stevens-Johnson syndrome / toxic epidermal necrolysis. MATERIALS AND METHODS: 29 Bullous pemphigoid, 14 Stevens-Johnson syndrome / toxic epidermal necrolysis patients and 92 health volunteers were included in the study. HLA-DRB1 and DQB1 alleles were assessed by polymerase chain reaction using specific primers. RESULTS: At a low-resolution level, HLA-DRB1*4 (p 0.02) and DRB1*14 (p 0.0015) alleles were statistically significantly revealed in bullous pemphigoid patients compared to health controls. Additionally, at the high-resolution level the predisposing to bullous pemphigoid HLA-DRB1*04:02 allele was also identified (p 0.01). At the low-resolution level of HLA-DQB1 typing we displayed protective and predisposing to bullous pemphigoid alleles HLA-DQB1*1 (p 0.01) and HLA-DQB1*2 (p 0.039) respectively. At the low-resolution level of HLA-DQB1 typing, the chances to obtain DQB1*03:02 allele were 3.71 times higher compared to healthy volunteers (p 0.01). In patients with Stevens-Johnson syndrome / toxic epidermal necrolysis, HLA-DRB1*4 allele was shown to be predisposing (p 0.03). For all other types of HLA alleles (DRB1 and DQB1) at the high-resolution level no any statistically significant results have been observed in these patients. CONCLUSION: We identified HLA-DRB1*4, DRB1*14, DRB1*04:02 alleles predisposing to the development of bullous pemphigoid, with the HLA-DQB1*1 allele being protective for the development of bullous pemphigoid and HLA-DRB1*4 allele predisposing to the development of severe drug reactions of Stevens-Johnson syndrome / toxic epidermal necrolysis. No any protective alleles in Stevens-Johnson syndrome / toxic epidermal necrolysis patients were detected.

Association of HLA-DRB1 alleles with status of antibodies to hepatitis B surface and e antigen.

Antigen presentation by HLA class II molecules to CD4+ T cells is an essential step for generating antibodies to hepatitis B antigens. In this study, we investigated the association between the HLA-DRB1 gene and the status of antibodies to hepatitis B surface and e antigens. Our results revealed a significant association between the status of anti-HBsAg and HLA-DRB1*04:03 (OR = 4.11, 95% CI = 1.50-10.84, p = 0.005, Padj. = 0.05) as well as HLA-DRB1*15:01 (OR = 1.74, 95% CI = 1.20-2.50, p = 0.002, Padj. = 0.045). MHC II binding predictions and in silico docking demonstrated strong binding affinity of HBsAg peptides to these two HLA-DRB1 molecules. Conversely, the status of anti-HBeAg was inversely associated with HLA-DRB1*14:54 (OR = 0.34, 95% CI = 0.18-0.64, p = 0.001, Padj. = 0.011), and in silico analysis revealed weak binding affinity of HBeAg peptides to HLA-DRB1*14:54. In conclusion, these findings support the involvement of HLA-DRB1 in humoral immunity against HBV infection.

Immunological markers of rheumatoid arthritis in the Moroccan population

Aim: few studies exist on HLA-DRB1 alleles and their association with RA in North Africa. We aimed to provide an evaluation of the distribution of the HLA-DRB1* and -DQB1* genes in Moroccan patients with early RA. Additionally, we sought to analyze the relationship between HLA molecules and the production of rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibodies (anti-CCP) in these patients. Methods: 65 patients with rheumatoid arthritis benefited from HLA class II typing (DRB1* and DQB1*) and testing for anti-CCP and RF antibodies. The frequency of HLA alleles was compared to that of 180 healthy controls. Logistic regression analysis was used to investigate the association of HLA-DR and -DQ molecules in the different subgroups according to anti-CCP and RF status. Results: The frequency of HLA-DRB1*04 and *11 alleles is increased in patients compared to controls (OR = 1.9; 95% CI (1.06-3.30), P=0.029; OR=2, 95% CI (1-3.83, P=0.047, respectively). 56 patients (86.1%) were RF positive, and 67.7% were anti-CCP positive. A significant increase in the frequency of DRB1*04 alleles was also noted in seropositive patients. Conclusion: Our results suggest the predisposition of the HLA-DRB1*04 allele and the seropositive status of patients with RA. This could be useful in predicting the evolution of RA and establishing a diagnosis in some patients at an early stage of disease use.

Identification of HLA alleles involved in immune thrombotic thrombocytopenic purpura patients from Turkey.

Thrombotic thrombocytopenic purpura (TTP) is one of the rare group disorders classified as thrombotic microangiopathies (TMAs). Approximately 90% of TTP developed immune-mediation by the formation of antibodies against the enzyme ADAMTS-13. The exact cause is unknown. To establish an association between human leukocyte antigen (HLA) and autoimmune basis, as susceptibility or protection against the disease, we contributed a study aiming to evaluate the role of HLA in immune-mediated TTP (iTTP). Considering epidemiological factors such as age, sex, ethnicity, and geographical origins, we contributed the study in our country, Turkey, which consist of a very heterogeneous population. Patients' data collection was retrospectively from electronic database on two University hospitals having big therapeutic apheresis service. Control arm was healthy people registered as stem cell donors matched in terms of age and sex. The frequency of HLA-DRB1 and HLA-DQB1 alleles between acquired TTP and the control group was compared using the chi-square method. Yates correction and logistic regression were performed on these results. A total of 75 iTTP patients and 150 healthy individuals enrolled to the study. HLA-DRB1∗11, HLA-DQB1∗03, HLA-DRB1∗11:01, HLA-DRB1∗14:01, HLA-DRB1∗13:05, HLA-DRB1∗11 + HLA-DQB1∗03 allele pair and HLA-DRB1∗15 + HLA- DQB1∗06 were proved to be susceptibility allele pairs for iTTP. HLA-DRB1∗15, HLA-DRB1∗01:01, HLA-DRB1∗07:01, HLA-DRB1∗13:01, HLA-DRB1∗14:54, HLA-DQB1∗05:01, HLA-DQB1∗02:02 and HLA-DRB1∗07 + HLA-DQB1∗02 allele pair were found to be protective against iTTP. Our findings support an association with iTTP across very heterogenous populations in Turkey.

The emergence of circulating activated autoreactive desmoglein 3-specific follicular regulatory T cells is associated with long-term efficacy of rituximab in patients with pemphigus vulgaris.

Pemphigus vulgaris (PV) is characterized by autoantibodies targeting keratinocyte adhesion proteins desmoglein (Dsg) 1 and 3, and by the human leukocyte antigen (HLA) predisposition allele HLA-DRB1*0402. Treatment using rituximab (RTX) combined with short-term corticosteroids (CS) allows disease control and long-lasting remission. The principal aim of this study was to evaluate the impact of RTX on the circulating subpopulations of Dsg3-specific T lymphocytes that specifically regulate B-cell responses: follicular helper T (Tfh) and follicular regulatory T (Tfr) lymphocytes. Using the HLA-DRB1*0402 tetramer loaded with the Dsg3 immunodominant peptide, we used flow cytometry to analyse the frequency, polarization and activation status of blood Dsg3-specific follicular T-cell populations at baseline, month (M) 6 and long-term follow-up (M60-90) from patients with PV. At baseline, we observed a predominance of Tfh1* and Tfh17 subsets and an underrepresentation of the Tfh2 subset among autoreactive Dsg3-specific Tfh cells compared with nonautoreactive Tfh cells. RTX treatment induced a decrease of autoreactive Tfh cells with no effect on their polarization during follow-up. In parallel, we observed the emergence of a Dsg3-specific Tfr subpopulation with a significant overexpression of the surface activation markers PD1, ICOS and CD25 that was not observed at the surface of autoreactive Tfh and nonautoreactive Tfr cells of the same patients with PV. In contrast, very few Dsg3-specific Tfr cells were observed in patients with PV who were treated with CS alone. Here we show that the emergence of circulating autoreactive Dsg3-specific Tfr cells is associated with the long-term efficacy of RTX in patients with PV.

High-Resolution HLA-DRB1 Allele Frequencies in a Romanian Cohort of Stem Cell Donors.

The goal of the current study was to determine the high-resolution frequencies of the HLA-DRB1 alleles among the analyzed Romanian cohort of healthy stem cell donors. Using Next Generation Sequencing (NGS), we estimated class II HLA-DRB1 allele frequencies to a 6-digit resolution through HLA typing in a Romanian cohort of healthy individuals. The study for HLA genotyping included 420 willing donors from the National Registry of Voluntary Hematopoietic Stem Cell Donors (RNDVCSH). In 2020 and 2021, peripheral blood samples were collected and transported to the Fundeni Clinical Institute. We used the Immucor Mia Fora NGS MFlex kit for HLA genotyping. Forty-one different alleles were detected in 420 analyzed samples, out of which the most frequent HLA-DRB1 alleles were DRB1*16:01:01 (12.6%), DRB1*11:04:01 (12.1%) and DRB1*03:01:01 (12%). The HLA-DRB1*11:01:02 and -DRB1*08:04:01, -DRB1*05:01:01, -DRB1*13:05:01, -DRB1*14:07:01, -DRB1*09:01:02, -DRB1*11:02:01, -DRB1*04:07:01, -DRB1*15:03:01, -DRB1*03:02:01, -DRB1*04:06:02, -DRB1*04:08:01, -DRB1*14:05:01 were identified only once. The results revealed similarities with countries belonging to the Eastern Europe, the Balkans and the Caucasus regions. Further studies on larger Romanian cohorts are needed for confirming the current results.

Clinical course of respiratory tuberculosis relapses in the Kazakh population depending on HLA-DRB1 gene alleles.

The study aimed to ascertain the prevalence and frequency of relapses of respiratory tuberculosis (TB) and examine the characteristics of its clinical progression in members of the Kazakh population based on the alleles of the HLA-DRB1 gene. Methods of clinical and genetic research, statistical processing and analysis of the obtained data were used to achieve this goal. The research led to an analysis of the statistical processing of clinical and genetic investigations that found out how often TB in the respiratory tract is found and how different HLA-DRB1 gene alleles affect the disease's progression. To find out how exposure to certain HLA-DRB1 gene alleles affects the chance of relapse, the number of times they were found was compared between people who had relapsed and people who had just been diagnosed with TB. The impact of these alleles on the progression of the disease was assessed based on their frequency of detection of different clinical forms of TB (infiltrative, fibro-cavernous, generalised, disseminated), unilateral and bilateral lung damage, lung tissue deterioration, and the presence of bacterial secretions. The highest detection rate for all comparisons had gene alleles HLA-DRB1*01 (9.5%), *08 (4.2%), *15 (3.9%), *09 (1.6%), *12 (1.3%), *13 (0.9%), *11 (0.2%). The study found that Kazakhs with the HLA-DRB1*01, *08, and 15 gene alleles are more likely to develop recurrent respiratory TB. The study's practical value lies in its potential to utilise its findings for the prompt identification and eradication of genetic variables contributing to the recurrence of TB.

Human leukocyte antigen class II (DRB1 and DQB1) alleles frequencies in patients with various forms of pemphigus among the Russian population

BACKGROUND: Autoimmune bullous dermatoses are known to be the most severe blistering conditions of skin. HLA-DRB1 and DQB1 alleles might play a crucial role in their onset. In pemphigus HLA class II molecules stimulate the division of T helper cells, which in turn stimulate B cells to produce antibodies to epidermal keratinocytes causing acantholysis. The HLA-DRB1 and DQB1 alleles’ frequencies studied in pemphigus in a vast variety of populations worldwide. However, as of yet, this mechanism was not investigated in Russian population. AIM: To estimate the prevalence of the HLA-DRB1 and DQB1 alleles at a low- and high-resolution levels in patients with various forms of pemphigus. We observed 86 patients with pemphigus vulgaris, 13 ― with pemphigus foliaceus, 6 patients with paraneoplastic pemphigus and 92 healthy volunteers. MATERIALS AND METHODS: HLA typing for DRB1 and DQB1 was performed with 50 nanogram DNA extraction and polymerase chain reaction. RESULTS: At a low-resolution level HLA-DRB1*4 and DRB1*14 alleles were statistically significant more frequent in pemphigus vulgaris and pemphigus foliaceus patients compared to those in control subjects, whereas HLA-DRB1*11, DRB*16, and DRB1*3 alleles were more frequent in healthy volunteers. At a high-resolution level, DRB1*04:02 allele was observed to show its statistically significant higher frequency in all variants of pemphigus, including paraneoplastic pemphigus. However, DRB1*14:05 HLA allele was more frequent in pemphigus vulgaris and pemphigus foliaceus patients, whereas DRB1*11:04 one was found to be 3.7 times more frequent in healthy controls. Additionally, at a low-resolution level for HLA-DQB1 alleles no statistically significant results were observed. However, at a high-resolution level the chances for more frequent indication of DQB1*03:02 allele were 7.09 times higher in pemphigus foliaceus group and 2.49 higher in pemphigus vulgaris patients compared to healthy volunteers. Moreover, DQB1*05:03 was identified more frequently in pemphigus vulgaris and paraneoplastic pemphigus groups of patients, whereas DQB1*03:01 allele was shown to be increased in the group of healthy donors. CONCLUSION: HLA-DRB1*4, DRB1*14, DRB1*04:02, DRB1*14:05, DQB1*03:02 and DQB1*05:03 alleles might be considered as the genetic markers for pemphigus vulgaris susceptibility, while HLA-DRB1*11, DRB*16, DRB1*3, DRB1*11:04 and DQB1*03:01 allelic groups appear to be protective for Russian population.

Association Between HLA-DRB1 Alleles and Graves' Disease in Asian Populations: A Meta-Analysis.

Graves' disease (GD) is an autoimmune disease that primarily affects the thyroid gland. It is the most common cause of hyperthyroidism. Genetic studies have shown that human leukocyte antigen (HLA) plays an important role in the development of GD. In this article, we performed a meta-analysis determined to evaluate the relationship between HLA-DRB1 alleles and GD. This meta-analysis included 9 studies (3582 cases in the case group and 23070 cases in the control group) and 27 alleles was performed. The combined results showed that, compared with the control group, GD patients have a significant increase in the frequency of DRB1*1403 (OR=2.50, 95% CI=1.78-3.51, pc<0.0001) and have a significant decrease in frequencies of DRB1* 0101 (OR=0.45, 95% CI=0.34-0.59, pc<0.0001) and DRB1*0701 (OR=0.44, 95% CI=0.35-0.55, pc<0.0001). The meta-analysis indicated that, in Asian populations, DRB1*1403 is a risk allele for GD, and DRB1*0101 and DRB1*0701 are protective against the occurrence of GD. We surprisingly discovered that the susceptibility alleles for GD in Asian populations are completely different from Caucasians and the protective alleles for GD in Asians are quite similar to those of Caucasians. The results of our study may provide new opportunities for gene-targeted therapy for GD in Asian populations.