Associations between human leukocyte antigens and renal function

Association between Human Leukocyte Antigen and End-Stage Renal Disease in Patients from Transylvania, Romania

End-stage renal disease (ESRD) is the final stage of chronic kidney disease. This study explored the association between human leukocyte antigen (HLA) and ESRD. The interaction between genetic and environmental factors may also play a role in the development of ESRD. The study included 2392 ESRD patients who were awaiting renal transplantation. Blood samples were genotyped by SSOP and SSP-PCR methods. Multivariate logistic regression analysis showed that HLA-A*11 (p = 0.027), HLA-A*34 (p = 0.017), HLA-A*69 (p = 0.012), HLA-B*41 (p < 0.001), HLA-B*50 (p = 0.004), HLA-DRB1*10 (p = 0.027), and HLA-DRB1*14 (p = 0.004) were positively associated with ESRD (OR > 1); HLA-DRB1*07 (p < 0.001), HLA-DRB1*08 (p = 0.005), and HLA-DRB1*13 (p < 0.001) were protective against ESRD (OR < 1); and the three-locus haplotype HLA-A*02-B*41-DRB1*03, containing one susceptible allele, was strongly associated with ESRD (p < 0.001, OR = 3.15). In conclusion, this retrospective analysis of HLA typing in patients with ESRD of various etiologies suggests that molecular data on the HLA polymorphism should be collected in order to identify high-risk ESRD patients and to improve graft survival after kidney transplantation.

Identification of genetic variants associated with diabetic kidney disease in multiple Korean cohorts via a genome-wide association study mega-analysis

BACKGROUND

The pathogenesis of diabetic kidney disease (DKD) is complex, involving metabolic and hemodynamic factors. Although DKD has been established as a heritable disorder and several genetic studies have been conducted, the identification of unique genetic variants for DKD is limited by its multiplex classification based on the phenotypes of diabetes mellitus (DM) and chronic kidney disease (CKD). Thus, we aimed to identify the genetic variants related to DKD that differentiate it from type 2 DM and CKD.

METHODS

We conducted a large-scale genome-wide association study mega-analysis, combining Korean multi-cohorts using multinomial logistic regression. A total of 33,879 patients were classified into four groups-normal, DM without CKD, CKD without DM, and DKD-and were further analyzed to identify novel single-nucleotide polymorphisms (SNPs) associated with DKD. Additionally, fine-mapping analysis was conducted to investigate whether the variants of interest contribute to a trait. Conditional analyses adjusting for the effect of type 1 DM (T1D)-associated HLA variants were also performed to remove confounding factors of genetic association with T1D. Moreover, analysis of expression quantitative trait loci (eQTL) was performed using the Genotype-Tissue Expression project. Differentially expressed genes (DEGs) were analyzed using the Gene Expression Omnibus database (GSE30529). The significant eQTL DEGs were used to explore the predicted interaction networks using search tools for the retrieval of interacting genes and proteins.

RESULTS

We identified three novel SNPs [rs3128852 (P = 8.21×10^-25), rs117744700 (P = 8.28×10^-10), and rs28366355 (P = 2.04×10^-8)] associated with DKD. Moreover, the fine-mapping study validated the causal relationship between rs3128852 and DKD. rs3128852 is an eQTL for TRIM27 in whole blood tissues and HLA-A in adipose-subcutaneous tissues. rs28366355 is an eQTL for HLA-group genes present in most tissues.

CONCLUSIONS

We successfully identified SNPs (rs3128852, rs117744700, and rs28366355) associated with DKD and verified the causal association between rs3128852 and DKD. According to the in silico analysis, TRIM27 and HLA-A can define DKD pathophysiology and are associated with immune response and autophagy. However, further research is necessary to understand the mechanism of immunity and autophagy in the pathophysiology of DKD and to prevent and treat DKD.

Immunogenetic aspects of idiopathic recurrent miscarriage in the Kazakh population

There are numerous scientific studies of recurrent miscarriage (RM) with possible causes, such as fetal chromosomal abnormalities, infectious agents, adverse environmental factors, bad habits, anatomical defects, thrombophilic disorders, etc. However, RM causes in 50% of cases remain unknown. These RM cases do not have any explainable etiology, and they require in-depth etiopathogenesis study, thus they are considered idiopathic RM. The purpose of this research is to study polymorphisms relationship of the immune response genes CX3CR1 (rs3732379, Val249Ile), CTLA4 (rs3087243, CT60 G/A), and HLA DQA1, DQB1, DRB1 (major histocompatibility complex, class II) with the idiopathic form of recurrent miscarriage (iRM) development in Kazakh population. Independent replicative TagMan genotyping for 302 patients with iRM and 300 women with normal reproduction was performed. It has been shown that carriage of unfavorable genotypes (Val/Ile, Val/Val) by the Val249Ile polymorphism of the CX3CR1 gene increases the risk of developing iRM by 1.43 times. Search for associations of genes allelic variants of HLA class 2 complex with iRM revealed *501 allele in DQA1 locus, *0301 in DQB1 locus, *10, *12, *15, *16 alleles in DRB1 locus, which increases the risk of developing iRM in Kazakh population with OR from 1.34 to 4.5. As a result of the study, obtained highly significant associations of immune response genes with the development of iRM in the Kazakh population indicate the possible involvement of the immune system interaction of mother cells with syncytiotrophoblast, which is realized by vascularization defects, defective embryo implantation, and leads to early pregnancies’ termination.

Systematic review of associations between HLA and renal function

Introduction

Kidney dysfunction is a highly significant disease, both in the United Kingdom and globally. Many previous studies have reported associations between human leukocyte antigens (HLA) and renal function; this systematic review attempts to identify, summarize and appraise all published studies of these associations.

Methods

A literature search was performed using Medline, Embase and Cochrane Central Register of Controlled Trials to identify papers whose keywords included each of the following concepts: HLA, renal failure and genetic association. A total of 245 papers were identified and assessed for eligibility; 35 of these were included in the final study.

Results

A total of 95 HLA types and 14 three‐locus haplotypes were reported to be associated with either increased or decreased renal function. A number of these findings were replicated by independent studies that reported 16 types were protective against renal dysfunction and 15 types were associated with reduced renal function. A total of 20 HLA types were associated with both increased risk of renal disease and decreased risk by independent studies.

Discussion

There is very little consensus on which HLA types have a protective or deleterious effect on renal function. Ethnicity may play a role, with HLA types possibly having different effects among different populations, and it is possible that the different primary diseases that lead to ESRD may have different HLA associations. Some of the studies may contain type I and type II errors caused by insufficient sample sizes, cohort selection and statistical methods. Although we have compiled a comprehensive list of published associations between renal function and HLA, in many cases, it is unclear which associations are reliable. Further studies are required to confirm or refute these findings.

Relevance of HLA gene polymorphisms in Romanian patients with chronic renal insufficiency undergoing renal transplantation

BACKGROUND

Chronic renal insufficiency (CRI) is a global public health problem with a high incidence in the Romanian population. In this study, we aimed to investigate genomic HLA polymorphisms in Romanian patients with CRI waiting for kidney transplantation. To determine the existence of a potential strong link between certain HLA polymorphisms and CRI, we also looked at HLA specificity combinations within the same locus or even different loci, referring to randomly inherited allelic combinations rather than potential haplotypes.

METHODS

A total of 2199 patients with CRI on the kidney transplantation waiting list were included. A total of 2786 healthy individuals were included as controls. Both patients and controls were assessed for both HLA I and class II genes. HLA genes were typed using the low-resolution method polymerase chain reaction sequence-specific primer.

RESULTS

Certain class I and class II HLA allele groups, genotypes and haplotypes were significantly more frequent in patients with CRI than in the control individuals (eg B* 40 (p ≤ .001, pc ≤ .001), C* 12 (p ≤ .001, pc ≤ .001), DRB1*14 (p = .0022, pc = .04), C*12,- (p < .001, pc < .001), A*01-C*15 (p = .0003, pc = .03) and A*02-C*12 (p = .0005, pc = .0486)).

CONCLUSIONS

HLA gene polymorphisms could be clinically relevant CRI-associated genetic profiles in Romanian patients with CRI.

Evaluation of Human Leukocyte Antigen Class I and Class II in End-Stage Renal Disease Occurrence in Indonesian Transplantation Patients

Background

Genetic studies of end-stage renal disease (ESRD), including those of human leukocyte antigen (HLA) genes, have been reported in several populations but have not yet been evaluated in Indonesia. Some studies have reported that these genes had a substantial role in ESRD. This study aims to analyze the association between HLA genes and ESRD within the Indonesian community.

Method

A retrospective study to investigate HLA class I and II alleles to find out the distribution of HLA-A, -B, -C, -DPB1, -DQB1, and -DRB1 in renal transplant recipients and to ascertain their role in susceptibility to ESRD was performed on totally 149 subjects, consisting of 69 ESRD patients and 80 healthy controls. HLA typing was determined using Luminex techniques. The allele and haplotype frequencies were compared between ESRD patients and controls.

Result

High-frequency alleles were HLA-A∗24 (43.6%), B∗15 (38.2%), C∗08 (30.8%), DRB1∗12 (47.3%), DQB1∗03 (50.6%), and DPB1∗13 (22.5%). HLA-A∗24 (p=0.01) and HLA-B∗35 (p=0.02) were associated with a protective effect, with OR 0.537 (95%CI 0.34–0.86) and 0.316 (95%CI 0.11–0.88), respectively. There were some two-locus haplotypes associated with susceptibility to ESRD, such as B∗15-DRB1∗12, B∗13-DRB1∗15, A∗02-B∗15, A∗02-C∗08, and B∗13-DQB1∗05. HLA-A∗02-B∗15-DRB1∗12 and A∗24-B∗13-DRB1∗15 appear to be associated with susceptibility to ESRD.

Conclusion

The allele groups of HLA-A∗24 and HLA-B∗35 are associated with protection from ESRD. Meanwhile, HLA-B∗13-DRB1∗15 and A∗24-B∗13-DRB1∗15 are the most frequent HLAs associated with ESRD in two-locus and three-locus haplotype, respectively.