Molecular Analysis of HLA Genes in Romanian Patients with Chronic Hepatitis B Virus Infection

Chronic Hepatitis B Virus Infection and HLA Variations in a Greek Population

Chronic hepatitis B is linked with considerable liver-related morbidity and mortality globally. Human leukocyte antigen (HLA) polymorphisms affect the susceptibility and outcome of many immune-mediated diseases and infections. Our aim was to study the impact of HLA alleles on HVB-infected individuals in a Greek population. In total, 107 patients with chronic HBV infection (cHBV group) and 101 with spontaneous clearance (SC-group) of hepatitis B surface antigen (HBsAg) were genotyped for HLA-A, HLA-B, HLA-C, HLA-DRB1, and HLA-DQB1 loci by single-specific primer polymerase chain reaction (PCR-SSP). The HLA alleles' frequencies were compared between the two patient groups and healthy individuals from the North Greece Bone Marrow Donor Registry (14506 samples). We found a significantly increased frequency of HLA-C*01 and HLA-DRB1*16 alleles in the cHBV group versus the SC-group. The frequency of HLA-A*01, HLA-B*08, HLA-C*01, HLA-C*08, HLA-DRB1*03, and HLA-DQB1*05 alleles was significantly higher in cHBV patients versus healthy individuals, while the frequency of the HLA-B*38 allele was significantly lower. Our study showed an association of specific HLA alleles with either susceptibility or protection against chronic HBV infection.

Cluster of Differentiation Markers and Human Leukocyte Antigen Expression in Chronic Lymphocytic Leukemia Patients: Correlations and Clinical Relevance

Chronic lymphocytic leukemia (CLL) is a distinct category of lymphoproliferative disorder characterized by the clonal expansion of mature B cells, followed by their accumulation in primary and secondary lymphoid organs. Cluster of differentiation (CD) markers such as CD79b, CD45, CD23, CD22 and CD81 serve as reliable prognostic indicators in CLL as well as the human leukocyte antigen (HLA) with its well-documented associations with various cancers. This study aims to investigate, for the first time, potential connections between HLA typing and CD marker expression in CLL. Although it is one of the most prevalent neoplasms, there is a need for biomarkers that can improve survival. This study included 66 CLL patients and 100 controls, with all samples analyzed using biochemical methods, flow cytometry, and cytomorphology. Next-generation sequencing was performed for HLA typing. The results indicate that several CD markers are statistically associated with different HLA alleles, specifically CD45 with HLA-C*07:01:01; CD79b with HLA-DPA1*02:01:02; CD23 with HLA-B*39:01:01; CD22 with HLA-B*49:01:01, HLA-C*07:01:01, HLA-DPB1*02:01:02, and HLA-DRB1*07:01:01; and CD81 with HLA-DPB1*04:02:01, HLA-DQA1*01:04:01, and HLA-DQB1*05:03:01. In conclusion, this research demonstrates significant statistical links between HLA genes and immunophenotypic markers in CLL patients, shedding new light on the immunological context of CLL.

HLA Genetic Diversity and Chronic Hepatitis B Virus Infection: Effect of Heterozygosity Advantage

This research aims to determine whether HLA heterozygosity confers a protective effect against hepatitis B virus infection by analyzing the relationship between HLA diversity and the risk of hepatitis B virus (HBV) infection. A total of 327 hepatitis B patients were selected and categorized based on their clinical status: 284 patients with chronic HBV infection and 43 patients with HBV-related liver cirrhosis (LC). The control group included 304 healthy individuals. HLA genotyping for 11 loci, including HLA class I and class II, was conducted using next-generation sequencing. The results of this study indicate a statistically significant negative correlation between HLA class II heterozygosity and the risk of HBV infection. Specifically, heterozygosity in HLA-DQB1 (OR = 0.49, 95% CI = 0.31-0.76, p = 0.01277) and HLA-DRB1 (OR = 0.42, 95% CI = 0.24-0.77, p = 0.01855) were significantly associated with protection. Subgroup analysis was conducted to explore the effect of HLA diversity among pathological subtypes (chronic hepatitis B and control group, liver cirrhosis and control group). For liver cirrhosis, compared with the control group, a decreased risk of LC was possibly associated with the heterozygosity of HLA class I locus B (OR = 0.24, 95% CI = 0.09-0.65, p = 0.0591), but this hypothesis was not confirmed by other studies. The diversity of HLA, measured by HLA heterozygosity, was associated with a protective effect against HBV infection.

High Resolution HLA-A, HLA-B, and HLA-C Allele Frequencies in Romanian Hematopoietic Stem Cell Donors

The HLA genes are associated with various autoimmune pathologies, with the control of the immune response also being significant in organs and cells transplantation. The aim of the study is to identify the HLA-A, HLA-B, and HLA-C alleles frequencies in the analyzed Romanian cohort. We performed HLA typing using next-generation sequencing (NGS) in a Romanian cohort to estimate class I HLA allele frequencies up to a six-digit resolution. A total of 420 voluntary donors from the National Registry of Voluntary Hematopoietic Stem Cell Donors (RNDVCSH) were included in the study for HLA genotyping. Peripheral blood samples were taken and brought to the Fundeni Clinical Institute during 2020-2021. HLA genotyping was performed using the Immucor Mia Fora NGS MFlex kit. A total of 109 different alleles were detected in 420 analyzed samples, out of which 31 were for HLA-A, 49 for HLA-B, and 29 for HLA-C. The most frequent HLA-A alleles were HLA-A*02:01:01 (26.11%), HLA-A*01:01:01 (12.5%), HLA-A*24:02:01 (11.67%), HLA-A*03:01:01 (9.72%), HLA-A*11:01:01, and HLA-A*32:01:01 (each with 8.6%). For the HLA-B locus, the most frequent allele was HLA-B*18:01:01 (11.25%), followed by HLA-B*51:01:01 (10.83%) and HLA-B*08:01:01 (7.78%). The most common HLA-C alleles were HLA-C*07:01:01 (17.36%), HLA-C*04:01:01 (13.47%), and HLA-C*12:03:01 (10.69%). Follow-up studies are ongoing for confirming the detected results.

HLA Gene Polymorphisms in Romanian Patients with Chronic Lymphocytic Leukemia

Materials and Methods

This study included 66 patients with CLL, diagnosed between 2020 and 2022, and 100 healthy controls. HLA class I and class II genes (HLA-A/B/C, HLA-DQA1/DQB1/DPA1/DPB1, and HLA-DRB1/3/4/5) were investigated using next-generation sequencing technology.

Results

Several HLA alleles were strongly associated with CLL. The most important finding was that HLA-DRB1∗04:02:01 (p=0.001, OR = 1.05) and HLA-DRB3∗02:01:01 (p=0.009, OR = 1.03) have a predisposing role in CLL development. Moreover, we identified that HLA-A∗24:02:01 0.01 (p=0.01, OR = 0.38), HLA-DQA1∗05:05:01 (p=0.01, OR = 0.56), HLA-DQB1∗03:02:01 (p=0.03, OR = 0.40), and HLA-DRB4∗01:03:01 (p=0.03, OR = 0.54 alleles have protective roles. Correlations between HLA expression and gender showed that women had a higher expression of protective HLA alleles when compared to men.

Conclusions

Our data are the first to indicate that in Romanian patients with CLL, the HLA-A∗24:02:01 and HLA-DQA1∗05:05:01 alleles have a protective role against CLL development, whereas HLA-DRB1∗04:02:01 and HLA-DRB3∗02:01:01alleles are positively associated with CLL.

Immunogenetic Background of Chronic Lymphoproliferative Disorders in Romanian Patients-Case Control Study

BACKGROUND AND OBJECTIVES

The implications of the genetic component in the initiation and development of chronic lymphoproliferative disorders have been the subject of intense research efforts. Some of the most important genes involved in the occurrence and evolution of these pathologies are the HLA genes. The aim of this study is to analyze, for the first time, possible associations between chronic lymphoproliferative diseases and certain HLA alleles in the Romanian population.

MATERIALS AND METHODS

This study included 38 patients with chronic lymphoproliferative disorders, diagnosed between 2021 and 2022 at Fundeni Clinical Institute, Bucharest, Romania, and 50 healthy controls. HLA class I and class II genes (HLA-A/B/C, HLA-DQB1/DPB1/DRB1) were investigated by doing high resolution genotyping using sequence specific primers (SSP).

RESULTS

Several HLA alleles were strongly associated with chronic lymphoproliferative disorders. The most important finding was that the HLA-C*02:02 (p = 0.002, OR = 1.101), and HLA-C*12:02 (p = 0.002, OR = 1.101) have a predisposing role in the development of chronic lymphoproliferative disorders. Moreover, we identified that HLA-A*11:01 (p = 0.01, OR = 0.16), HLA-B*35:02 (p = 0.037, OR = 0.94), HLA-B*81:01 (p = 0.037, OR = 0.94), HLA-C*07:02 (p = 0.036, OR = 0.34), HLA-DRB1*11:01 (p = 0.021, OR = 0.19), and HLA-DRB1*13:02 (p = 0.037, OR = 0.94), alleles have protective roles.

CONCLUSIONS

Our study indicates that HLA-C*02:02 and HLA-C*12:02 are positively associated with chronic lymphoproliferative disorders for our Romanian patients while HLA-DRB1*11:01, HLA-DRB1*13:02, and HLA-B*35:02 alleles have a protective role against these diseases.