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.

Malaria is a mosquito-borne disease caused by Plasmodium parasites, responsible for a significant impact on public health in several tropical and sub-tropical countries. The majority of infection cases are classified as uncomplicated malaria, causing mild symptoms such as fever and headache. However, the disease may progress to severe malaria and death if the infection is not properly treated. Furthermore, malaria poses a major concern for children, pregnant women and immunosuppressed individuals. Exacerbated inflammation is characteristic of severe malaria cases. The C-C chemokine receptor type 5 (CCR5) is an important molecule for leukocyte migration and regulation of inflammation. Although widely known as an HIV-1 co-receptor, CCR5 also affects the susceptibility and progression of autoimmune and inflammatory diseases. There is evidence supporting the participation of CCR5 in malaria manifestations, with the evaluation of CCR5 gene expression levels suggested as a marker to monitor malaria severity. Certain genetic variants in the CCR5 gene affect CCR5 expression, potentially altering CCR5-mediated inflammatory responses during malaria infection. However, the complex influences of CCR5 on malaria remain underexplored. Therefore, this review examines and updates the role of CCR5 in various contexts of malaria infection, including uncomplicated malaria, Plasmodium/HIV co-infection, pregnancy and severe (cerebral) malaria.

This study sought to investigate the association between interleukin-10 (IL10) polymorphisms and susceptibility to Sjögren's syndrome. A systematic search of the Medline, Embase and Web of Science databases was conducted to identify relevant articles from inception to April 2024. No restrictions were placed on race, ethnicity or geographic area, but only studies published in English were included. A meta-analysis was conducted to evaluate the association among the IL10-1082 G/A (rs1800896), -819 C/T (rs1800871) and -592 C/A (rs1800872) polymorphisms, as well as their haplotypes and the risk of developing Sjögren's syndrome. The included studies involved 998 Sjögren's syndrome patients and 1576 controls. Ten studies were included in the meta-analysis. Meta-analysis of the IL10-1082 G/A polymorphism revealed no significant association with Sjögren's syndrome (odds ratio [OR] = 1.115, 95% confidence interval [CI]: 0.888-1.401, p = 0.343), with stratification by ethnicity yielding consistent results for Europeans and Latin Americans. Similarly, the IL10-819 C/T polymorphism was not associated with Sjögren's syndrome in any study subjects (OR = 0.859, 95% CI: 0.648-1.138, p = 0.290). The IL10-592 C allele also exhibited no association with Sjögren's syndrome (OR = 1.131, 95% CI: 0.776-1.646, p = 0.522). However, the GCC carrier status demonstrated a significant association with Sjögren's syndrome across all study subjects (OR = 1.496, 95% CI: 1.200-1.865, p < 0.001), particularly in Europeans (OR = 1.444, 95% CI: 1.085-1.921, p = 0.012) and Latin Americans (OR = 1.324, 95% CI: 1.115-2.366, p = 0.012). A significant protective effect of the homozygous ATA/ATA haplotype on Sjögren's syndrome was found in Europeans (OR = 0.320, 95% CI: 0.121-0.846, p = 0.022). This meta-analysis indicates a significant link between carrying the GCC haplotype of the IL10-1082 G/A, -819 C/T and -592 C/A polymorphisms and an increased susceptibility to Sjögren's syndrome. Conversely, the homozygous ATA/ATA haplotype appears to confer protection against the risk of Sjögren's syndrome, particularly in European populations.

This study aims to investigate the association of rs11203366, rs11203367, rs874881, rs2240340 and rs1748033 polymorphisms of protein-arginine deiminase type 4 (PADI4) gene with the risk of rheumatoid arthritis (RA) through a meta-analysis that was followed with a bioinformatics approach. The data were collected from reputable articles and underwent quantitative analysis, followed by in silico analysis using some bioinformatics tools. The results showed that rs874881 polymorphism in Latino (G vs. C: OR = 1.35, 95% CI = 1.11-1.65, p = 0.003; GG + CG vs. CC: OR = 2.02, 95% CI = 1.41-2.89, p = 0.0001; CG vs. CC + GG: OR = 1.38, 95% CI = 1.04-1.83, p = 0.027; GG vs. CC: OR = 2.09, 95% CI = 1.35-3.23, p = 0.001; CG vs. CC: OR = 1.98, 95% CI = 1.36-2.87, p = 0.00033) and rs1748033 in Caucasian population (T vs. C: OR = 1.25, 95% CI = 1.07-1.45, p = 0.005; TT vs. CT + CC: OR = 1.34, 95% CI = 1.09-1.64, p = 0.005, TT + CT vs. CC: OR = 1.26, 95% CI = 1.09-1.44, p = 0.001; TT vs. CC: OR = 1.59, 95% CI = 1.13-2.23, p = 0.007; CT vs. CC: OR = 1.20, 95% CI: 1.04-1.39, p = 0.015) are associated with increased risk of RA. Moreover, rs11203366 (G vs. A: OR = 1.46, 95% CI = 1.19-1.78, p = 0.0002, GG vs. AG + AA: OR = 1.42, 95% CI = 1.01-2.01, p = 0.043; GG + AG vs. AA: OR = 2.03, 95% CI = 1.45-2.86, p = 0.00004; GG vs. AA: OR = 2.29, 95% CI = 1.49-3.51, p = 0.0002; AG vs. AA: OR = 1.93, 95% CI = 1.35-2.76, p = 0.0003) and rs11203367 (T vs. C: OR = 1.50, 95% CI = 1.23-1.83, p = 0.00007; TT vs. CT + CC: OR = 1.56, 95% CI = 1.12-2.18, p = 0.009; TT + CT vs. CC: OR = 2.02, 95% CI = 1.43-2.84, p = 0.00007, TT vs. CC: OR = 2.43, 95% CI = 1.59-3.71, p = 0.0004; CT vs. CC: OR = 1.86, 95% CI = 1.30-2.68, p = 0.0007) had an impact in the Latino population. Bioinformatics tools showed the effect of these polymorphisms on gene function. These findings suggest that rs11203366, rs11203367, rs874881 and rs1748033 polymorphisms may be genetic risk factors for RA. Moreover, differences between populations suggest that ethnicity may play an important role in the effect of these polymorphisms on RA risk.

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) 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) 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.

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.

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.

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.

Chronic inflammation triggered by hepatitis B (HBV) and hepatitis C (HCV) viruses elevates interleukin 6 (IL-6) levels, activating pathways that cause liver damage and contribute to hepatocellular carcinoma (HCC) development. In this study, we assessed IL-6 levels and explored the correlation between the rs1800795 and rs1800797 variants of the IL-6 gene and the risk of developing HCC. We conducted a case-control study involving 314 participants. Among them, 157 were HCC patients (94 anti-HCV, 22 HBsAg and 41 metabolic dysfunction-associated steatotic liver disease [MASLD]) and 157 controls. Genotyping for IL-6 rs1800795 and rs1800797 polymorphisms was performed using real-time polymerase chain reaction (PCR). Additionally, plasma IL-6 levels were determined using enzyme-linked immunosorbent assay. The IL-6 levels were notably higher in patients compared to controls (p < .0001). Among HCC patients, those with MASLD exhibited higher plasma IL-6 levels than those with HCV and HBV (p = .003). In male HCC patients, IL-6 levels were significantly elevated compared to controls (p < .0001). Similarly, female patients showed significantly higher IL-6 levels compared to female controls, though still lower than in male HCC patients (p = .023). However, no significant difference was observed in IL-6 levels between male and female HCC patients (p = .129). Contrastingly, the genotype and allele distributions of the rs1800795 and rs1800797 polymorphisms in the IL-6 gene displayed no association with HCC development (all p > .05). In Moroccan HCC patients, chronic liver inflammation is characterized by elevated levels of IL-6, potentially playing a role in the progression of liver disease and tumourigenesis.

Despite recent advances that have improved outcomes following intestinal transplantation (ITx), achieving long-term patient survival and rejection-free survival is still challenging. Understanding the relevance of pre-transplant human leukocyte antigen (HLA) donor-specific antibody (DSA) in ITx and the immunomodulatory potential of the liver within the allograft is crucial to providing an accurate assessment of pre-transplant immunological risk, which could influence and improve post-transplant outcomes further. This was the primary objective of this retrospective study of 95 adult ITx transplants which took place at Cambridge University Hospitals (United Kingdom) between 2007 and 2019. Two novel programs were developed and validated to identify DSA (tested by Luminex single antigen beads) in this dataset. Data analysis utilised Kaplan-Meier survival methods, and statistical analysis was performed using log-rank tests and adjusted Cox models. Fifty-four (57%) ITx cases contained a liver, and 36 (38%) were sensitised to HLA. Pre-transplant DSA > 500 mean fluorescent intensity appeared to negatively affect post-ITx patient survival and rejection outcomes. Additionally, liver-inclusive allografts seemed to show particular resistance to HLA class I DSA. Our data hints towards consistency with other ITx studies where deleterious effects of DSA have been demonstrated, and where liver inclusion is protective from HLA class I DSA. This is in line with current national guidelines for immunological risk. Our publicly available research programs could support future large or multicentre studies where statistically relevant data might be gained.

Signal transducer and activator of transcription 4 (STAT4) plays a crucial role in the host immune response against Mycobacterium tuberculosis. This study investigates the association between STAT4 gene polymorphisms and pulmonary tuberculosis (TB) risk in the Moldavian population. A total of 272 TB patients and 251 community-matched controls underwent screening for functional single-nucleotide polymorphisms (SNPs) rs897200 and rs7574865 in the STAT4 gene. The minor T allele and the TT/CT genotype of rs897200 demonstrated a significant association with reduced pulmonary TB risk (allelic model: adjusted OR = .74, p = .025; log-additive model: adjusted OR = .72, p = .02; and dominant model: adjusted OR = .65, p = .023), indicating a protective effect. Similar associations, characterized by an even more pronounced reduction in risk, were observed among females and late-onset TB patients (>44 years). No significant associations were found for rs7574865. In addition, a combined genotype analysis incorporating 43 SNPs from our previous studies revealed potential associations, such as STAT4 rs897200 CT with IFNG rs2430561 AA (adjusted OR = .36, p = .0025) and STAT4 rs897200 CT with TNFA rs1800629 GA (adjusted OR = .33, p = .0012). This study emphasizes the significant association of STAT4 rs897200 with pulmonary TB risk in the Moldavian population, underscoring its role in the disease development.

Vitamin D status has been involved with coronavirus disease 19 (COVID-19) severity. This may be mediated by vitamin D metabolism regulatory genes. Of interest is the vitamin D receptor (VDR) gene, which has been previously associated with other inflammatory and respiratory diseases. In order to investigate the role of VDR gene polymorphisms in COVID-19 severity and outcome, a total of 292 COVID-19 patients were classified according to severity in moderate (n = 56), severe (n = 89) and critical (n = 147) and, according to outcome in survivor (n = 163) and deceased (n = 129), and analysed for FokI and TaqI VDR gene polymorphisms by polymerase chain reaction-based restriction enzyme digestion. The FokI and TaqI single nucleotide polymorphisms (SNPs) were not associated with COVID-19 severity or mortality individually but when analysed by haplotype, TC was associated with an increased risk of presenting critical COVID-19. Additionally, FokI CT genotype was more frequent in COVID-19 patients with hypertension, and T allele carriers presented higher aspartate aminotransferase levels. Our results suggest a relationship between VDR FokI and TaqI SNPs and COVID-19 severity in Mexican population. Although there are some previous reports of VDR polymorphisms in COVID-19, this represents the first report in Latin American population. Further studies on other populations are encouraged.

Toll-like receptors (TLRs) play an important role in innate immunity. Previous studies have shown that single nucleotide polymorphisms (SNPs) in the genes coding for these innate immune molecules can affect susceptibility to and the outcome of certain diseases. The aim of the present study was to examine the clinical relevance of well-studied TLR1-4 SNPs in individuals who are prone to infections. Four functional SNPs, TLR1 rs5743618 (1805C > A, Ser602Ile), TLR2 rs5743708 (2258G > A, Arg753Gln), TLR3 rs3775291 (1234C > T, Leu412Phe) and TLR4 rs4986790 (896A > G, Asp299Gly), were analysed in 155 patients with recurrent respiratory infections (n = 84), severe infections (n = 15) or common variable immunodeficiency (n = 56), and in 262 healthy controls, using the High Resolution Melting Analysis method. Polymorphisms of TLR2 rs5743708 (odds ratio [OR] 3.16; 95% confidence interval [CI] 1.45-6.83, p = .004, ap = .016) and TLR4 rs4986790 (OR 1.8; 95% CI 1.05-3.12, p = .028, ap = .112) were more frequent in patients with recurrent or severe infections than in controls. Interestingly, seven patients were found to carry both variant genotypes of TLR2 and TLR4, whereas none of the control group carried such genotypes (p  ≤ .0001). Moreover, TLR2 polymorphism was associated with increased risk for acute otitis media episodes (OR, 3.02; 95% CI 1.41-6.47; p = .012). This study indicates that children and adults who are more prone to recurrent or severe respiratory infections carry one or both variant types of TLR2 and TLR4 more often than control subjects. Genetic variations of TLRs help explain why some children are more susceptible to respiratory infections.

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.