International Journal of Immunogenetics最新文献

Carriage of HLA-DQA1*05 is thought to increase the formation of anti-tumour necrosis factor alpha (TNF-α) antibodies, reducing the drug efficacy in Crohn's disease (CD) patients. However, little data are currently available for small-bowel Crohn's disease (SB-CD). A specific assessment of the impact of HLA-DQA1*05 on the clinical response to treatment with infliximab (IFX), a TNF-α antagonists, in SB-CD patients is necessary. We conducted a single-center retrospective study that included 106 SB-CD patients treated with IFX. The serum samples were collected for antibodies to infliximab (ATI) testing and HLA-DQA1*05 genotyping. Double-balloon enteroscopy (DBE) was performed following the IFX treatment, with endoscopic outcomes evaluated using the partial simple endoscopic score for CD (pSES-CD), whereas the clinical response was assessed with the Crohn's disease activity index (CDAI). Multivariate logistic regression and multivariate COX regression analyses were employed to analyze the correlation of the HLA-DQA1*05 genotypes with other clinical variables. In this study, 30.2% of SB-CD patients carried the HLA-DQA1*05 allele, which significantly increased their risk of ATI generation (odds ratio [OR] = 2.337, p = .043), but it was not associated with the clinical response to IFX and drug persistence (OR = 2.356, p = .145; OR = 0.457, p = .249). The endoscopic remission rates were 40.6% (13/32) and 55.4% (41/74) in HLA-DQA1*05 carriers and non-carriers, respectively. HLA-DQA1*05 was not associated with endoscopic remission (OR = 0.684, p = .414). The HLA-DQA1*05 variant is identified as a significant risk factor of ATI formation in Chinese patients with SB-CD, but is not associated with the clinical response of IFX treatment and endoscopic remission of SB lesions.

Type 2 diabetes (T2DM) is characterised by insulin resistance and a relative shortage of insulin secretion. Tumour necrosis factor-α (TNF-α) plays an important role in insulin resistance by impairing insulin signal transduction. The variants of the TNF-α promoter region are considered to influence its transcription and are associated with the TNF-α level. Therefore, it is worth detecting the association of the variants in the TNF-α gene with the development of T2DM. The aim of this study was to investigate the association of five variants (rs1799964, rs1800630, rs1799724, rs1800629 and rs361525) in the TNF-α gene promoter region with T2DM in a Chinese Han population. A total of 713 subjects with T2DM and 751 nondiabetic subjects were genotyped using the TaqMan method. The associations of the five variants with the development of T2DM were evaluated. The associations of the five variant genotypes with metabolic traits in nondiabetic subjects were analysed. Our data showed that the A allele of rs1800629 could increase the risk of developing T2DM (p = .002, OR = 1.563; 95% CI: 1.18-2.08). According to inheritance mode analysis, compared with the G/G genotype, the G/A+2A/A genotype of rs1800629 showed a risk effect on T2DM in the log-additive mode (p = .002, OR = 1.56; 95% CI: 1.17-2.07). The haplotypes analysis identified that the rs1799724-rs1800629CA was associated with high risk of the development of T2DM (p = .002, OR = 1.559, 95% CI: 1.173-2.072). Conversely, the rs1799724-rs1800629CG was a protective haplotype of T2DM (p = .001, OR = 0.732, 95% CI: 0.607-0.884). Moreover, compared with the rs1799964 (T/T+C/T) genotype, the rs1799964 C/C genotype was associated with higher glycosylated haemoglobin (HbA1c) levels in nondiabetic subjects (p = .017). Our results revealed that the rs1800629 in the TNF-α gene promoter region was associated with T2DM in a Chinese Han population.

The angiotensin-converting enzyme (ACE) gene plays a significant role in regulating immune responses and inflammatory processes, thus impacting the susceptibility to systemic lupus erythematosus (SLE). Understanding how single-nucleotide polymorphisms (SNPs) within the ACE gene contribute to the genetic susceptibility to SLE is essential for comprehending the disease's aetiology. Therefore, exploring this relationship in the Hainan region of China is crucial for gaining insights into the pathogenesis of SLE. This study comprised 428 participants, including 214 SLE patients and 214 healthy controls. Clinical data were gathered, and blood samples were collected. Genotyping of three SNPs (rs4459609, rs4309, rs1987692) within the ACE gene was performed using SNaPshot technology. The frequencies of alleles and genotypes of these three SNPs were compared between the SLE and control groups. Combining different genetic models and haplotype analysis, the correlation between ACE gene polymorphisms and SLE was investigated. Both study groups exhibited conformity with the Hardy–Weinberg genetic equilibrium (p > .05). Significant differences were observed in the genotype frequency distributions of ACE genes rs4459609, rs4309 and rs1987692 between the SLE and control groups (p = .009, .008, .032, respectively). The frequency of allele T at rs4309 was significantly higher in the SLE group than in the control group, correlating significantly with increased SLE risk (odds ratio [OR] = 1.527, 95% confidence interval [CI] = 1.147–2.035). Associations among ACE rs4459609, rs4309 and rs1987692 polymorphisms and increased susceptibility to SLE were found under co-dominant and dominant models (p < .05, with OR values and 95% CI greater than 1). Linkage disequilibrium was observed among rs4459609, rs4309 and rs1987692, and haplotype analysis revealed a significantly higher frequency of the CCA haplotype in the control group compared to the SLE group (p < .001). The ACA and ATA haplotypes showed significantly higher frequencies in the SLE group than in the control group (p = .014, p = .013, respectively). ACE gene polymorphisms are associated with the genetic susceptibility to SLE. The AC and AA genotypes at the rs4459609 locus, the TT genotype and T allele at the rs4309 locus and the AC and CC genotypes at the rs1987692 locus may serve as risk factors for the development of SLE.

Narcolepsy is a sleep disorder caused by an apparent degeneration of orexin/hypocretin neurons in the lateral hypothalamic area and a subsequent decrease in orexin/hypocretin levels in the cerebrospinal fluid. Narcolepsy is classified into type 1 (NT1) and type 2 (NT2). While genetic associations in the human leukocyte antigen (HLA) region and candidate autoantibodies have been investigated in NT1 to imply an autoimmune origin, less is known about the pathogenesis in NT2. Twenty-six NT1 and 15 NT2 patients were included, together with control groups of 24 idiopathic hypersomnia (IH) patients and 778 general population participants. High-resolution sequencing was used to determine the alleles, the extended haplotypes, and the genotypes of HLA-DRB3, -DRB4, -DRB5, -DRB1, -DQA1, -DQB1, -DPA1, and -DPB1. Radiobinding assay was used to determine autoantibodies against hypocretin receptor 2 (anti-HCRTR2 autoantibodies). NT1 was associated with HLA-DRB5*01:01:01, -DRB1*15:01:01, -DQA1*01:02:01, -DQB1*06:02:01, -DRB5*01:01:01, -DRB1*15:01:01, -DQA1*01:02:01, -DQB1*06:02:01 (odds ratio [OR]: 9.15; p = 8.31 × 10⁻⁴) and HLA-DRB5*01:01:01, -DRB1*15:01:01, -DQA1*01:02:01, -DQB1*06:02:01, -DRB4*01:03:01, -DRB1*04:01:01, -DQA1*03:02//03:03:01, -DQB1*03:01:01 (OR: 23.61; p = 1.58 × 10⁻⁴) genotypes. Lower orexin/hypocretin levels were reported in the NT2 subgroup (n = 5) that was associated with the extended HLA-DQB1*06:02:01 haplotype (p = .001). Anti-HCRTR2 autoantibody levels were not different between study groups (p = .8524). We confirmed the previous association of NT1 with HLA-DQB1*06:02:01 extended genotypes. A subgroup of NT2 patients with intermediate orexin/hypocretin levels and association with HLA-DQB1*06:02:01 was identified, indicating a possible overlap between the two distinct narcolepsy subtypes, NT1 and NT2. Low anti-HCRTR2 autoantibody levels suggest that these receptors might not function as autoimmune targets in either NT1 or NT2.

Vitamin D deficiency is widespread and poses a significant health concern, as emerging research links it to allergic diseases owing to its immunomodulatory functions. The optimal functioning of vitamin D and its activation depend on its nuclear receptor, vitamin D receptor (VDR). Genetic variants of VDR have been explored as potential factors in autoimmune and allergic diseases, with limited studies on their association with allergic rhinitis (AR). The present investigation aims to analyse the role of three VDR genetic variants – TaqI, FokI and BsmI – in AR susceptibility and their impact on VDR mRNA and serum vitamin D levels. A total of 550 subjects, consisting of 250 AR cases and 300 age- and gender-matched controls, underwent genotyping by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). VDR mRNA and vitamin D levels were determined by quantitative real-time PCR and chemiluminescence, respectively. Although TaqI did not exhibit significant differences, FokI demonstrated a noteworthy association with AR, particularly with the CC genotype (odds ratio [OR]: 3.34; confidence interval [CI]: 1.79–6.23). Similarly, BsmI revealed an increased risk for AR, with the GA + AA genotypes showing a 2.2-fold elevated risk (OR: 2.20; CI: 1.53–3.16). VDR mRNA expression was threefold lower in AR patients (p < .0001), accompanied by reduced serum vitamin D levels (p < .0001). In addition, CC (p = .01) and AA (p = .02) genotypes of FokI and BsmI were associated with reduced VDR mRNA levels, whereas TaqI showed no such association. Similarly, heterozygous genotypes of TaqI and FokI, as well as homozygous AA of BsmI, correlated with lower serum vitamin D levels (p < .001). This study emphasizes the intricate relationship among VDR genetic variations, altered VDR activity, immune modulation and vitamin D metabolism in AR. Further research involving diverse populations is crucial for confirming and generalizing these findings, paving the way for personalized therapeutic interventions in vitamin D–related disorders.

Clarke and Nadat (2024) provide an overview of techniques currently used to detect HLA antigens and antibodies and describe approaches that attempt to quantify incompatibility between a transplant recipient and her/his donor per their HLA typing. They proceed to mention assays investigating qualities of the antibodies such as affinity and avidity as well as glycosylation state and describe approaches to study T and B lymphocytes’ clonality and receptor repertoires. Lastly, they briefly talk about tests to assess allo-immune memory and mention some assays to assess graft injury.

I applaud the authors for providing a condensed menu of tests available for transplant immunologists. I do, however, fear that if the task was to provide new perspective on evaluating compatibility between recipient and donor, this review misses the forest for the trees.

Immune mechanisms are controlled by thousands of genes that drive much of the variability in immune responses, whether those are to pathogens, susceptibility to autoimmune diseases, or susceptibility to allo-stimulation. Each of these genes had evolved and diverged through mechanisms of essentiality, redundancy, and adaptability to provide diverse routes for the best protection to different populations under their own local threats (Quintana-Murci, 2019). These evolutionary forces also necessitated the generation of pathways for redundancy in immune pathways, such that inhibition of one path would not lead to the demise of the individual/population. This means that testing for one, or even a few, pathways will not necessarily correlate with the overall composite response. We should further consider that beyond the ‘pure’ immune genes, additional variables participate in orchestrating an immune response including factors such as age and gender, and environmental exposures. Thus, the landscape of genes and molecules associated with immune activation is vast and polymorphic. We can opt to develop and validate more and more assays to assess allo-immunity as described in the aforementioned review, or we can direct our attention to the elephant in the room—better understanding of the underlying mechanisms leading to differential immunogenicity.

As Histocompatibility and Immunogenetics (H&I) professionals, we appreciate that much of the adaptive immune response (and at least some of the innate response) is guided by the individual's specific HLA molecules. Those are the molecules that control much of our thymic education, that are instrumental for antigen processing and presentation, and that are involved in the most crucial steps of immune activation. The first step in a decision-making tree is ‘identify the problem’. In the context of allo-stimulation, we must therefore first understand why one's immune system perceives one HLA mismatch as more immunogenic and another mismatch as less immunogenic. With this information, deciphering immune activati

Penicillin allergy is a potentially life-threatening condition that is common among patients. However, the genetic associations with penicillin allergy are not yet recognized for prevention or diagnosis, particularly in East Asian populations. We conducted a retrospective case–control study using data from the Taiwan Precision Medicine Initiative and analysing DNA samples to identify eight major MHC Class I and Class II loci. We employed imputation methods for accurate HLA typing and enrolled 17,827 individuals who received penicillin. Logistic regression analyses were utilized to explore associations between HLA genotypes, comorbidities and allergy risk, while simultaneously conducting a subgroup analysis to explore the association between HLA genotypes, comorbidities and the severity of allergic reactions. Our study assigned 496 cases to the penicillin allergy group and 4960 controls to a matched group. The risk of penicillin allergy was significantly higher with HLA-DPB1*05:01 (OR = 1.36, p = .004) and HLA-DQB1*05:01 (OR = 1.54, p = .03), with adjusted p-values of .032 and .24, respectively. Urticaria was identified as a separate risk factor (OR = 1.73, p < .001). However, neither the HLA alleles nor the comorbidities had a significant relationship with the risk of severe penicillin-induced allergy. HLA-DPB1*05:01 was found to be significantly associated with penicillin allergy reactions among the Taiwanese population.

The purpose of this review is to encourage a new perspective on the question of donor–recipient compatibility and post-transplant assessment of graft health based on functional measures. The premise is that we should be better sighted on what (and how) the immune system responds toward rather than what is merely there. Continuance of the pursuit of further and better definition of antigens and antibodies is not however discouraged but seen as necessary to improved understanding of the structural correlates of functional immunity. There currently exists, in the opinion of the authors, an opportunity for histocompatibility and immunogenetics laboratories to develop and widen their scope of involvement into these new areas of laboratory activity in support and to the benefit of the transplant programmes they serve.