Investigation of Human Leukocyte Antigen (HLA) Class I and II Alleles and Hepatitis C Virus (HCV) Genotypes in Patients Infected with HCV

Hepatitis C virus (HCV) is a major public health problem with more than 130-180 million people infected worldwide. Several studies in different populations have reported the association of human leukocyte antigen (HLA) genotypes, and HCV viral load, and genotypes. The aim of this study was to investigate a possible association between HLA class I and II alleles in HCV-infected patients and healthy individuals. This study was conducted on 82 individuals characterized as group A: 29 healthy screened blood donors as controls; group B: 7 patients positive for HCV antibodies with non-detectable HCV-RNA; and group C: 46 patients positive for HCV antibodies with detectable HCV-RNA. HCV seropositivity was determined by enzyme immuno-assay (EIA), confirmed by recombinant immune blotting assay (RIBA). Viral RNA was detected by qualitative polymerase chain reaction (PCR) followed by determination of viral load by quantitative RT-PCR. HCV DNA amplicons were utilized by immune blotting hybridization assay for detection of HCV genotypes in HCV-infected groups. HLA genotyping was performed for all studied groups. HCV genotype 1 (1a, 1b) was the commonest among the high viral load (> 500.000 copies/ml) HCV-infected patients (70%), while genotype 4 was found in only (18.75%) low viral load (< 500.000 copies/ml) HCV-infected patients. Each group was characterized exclusively by certain HLA genotypes. HLA-A99, B6, B14, B15, B45, B78, DQ3, and DQ22 were only detected in group A subjects. HLA-B70 was observed only in group B, and HLA-A21, A34, A69, B0, B21, B39, B46, B56, B58, B60, B65, B71, B75, DR6, DR9, DR18, and DQ9 were detected in group C only. High frequencies 44.8%, 37.9%, 34.5%, and 27.6% for HLA- DQ6, DQ2, A2 and B51, respectively were observed in healthy controls. Meanwhile, 54.3%, 34.8%, 28.3%, 26.1%, 23.9%, and 17.4% frequencies were observed for HLA-DQ2, DQ6, A1, A2 and DR17, DR4, B51, and B0, respectively in HCV-infected patients. The HLA genetic makeup maybe a contributing factor for determining HCV infection outcome, the virus clearance or chronic persistence infection. Further researches on a larger scale are needed.