Impact of Human Leukocyte antigen (HLA) typing on the outcome of Hepatitis C Virus (HCV) infection in Egyptian patients

Abstract

Hepatitis C (HCV) is the most pressing public health challenge in Egypt; 10% of Egyptians between 15 – 59 years of age had been infected with HCV infection, while 7% are chronic active hepatitis C patients. Although, progresses were made in antiviral therapies; this cannot ensure controlling the virus infection due to many reasons one of which is the lack of HCV vaccine. Achievement of this goal will be fulfilled from a clear understanding of virus–host interactions and protective immunity in HCV infection taking in consideration the ethnic and geographical variations. This preliminary study was designed aiming to find out the frequencies of HLA Class I and II alleles in HCV infected Egyptian patients for assessing the correlations between HLA phenotypes and the consequences of HCV infection. Two hundreds and eighty two HCV subjects were enrolled in the present study and they were categorized into 7 groups; Group1: Spontaneous clearance (SC: n=37), Group 2: Asymptomatic HCV infection (AS: n=40), Group 3: Chronically infected HCV patients (CHCm: n= 86 with no, mild or moderate fibrosis); Group 4: Chronically infected HCV patients (CHCa: n=12 with advanced fibrosis); Group 5: Cirrhotic liver disease either compensated or decompensated (LC: n=42), Group 6: Hepatocellular Carcinoma patients (HCC: n=40), Group 7: Healthy Controls (N: n=25). HLA alleles were typed by DNA based Typing method “LABType® sequence-specific oligonucleotide (SSO) probes” for HLA-A, HLA-B, HLA-C, HLA-DRB1 and HLA-DQ (A and B) alleles from peripheral blood of all participants. The results of this work implicate that special HLA patterns were found; HLA-DRB1*03, -DRB1*14 antigen may play a role in viral persistence. While, HLA-C*05, -DRB1*11, -DQA1*05 and -DQB1*03 is associated with viral clearance. In conclusion, HLA system is an ideal system in which to explore predictions on the outcome of HCV infections in Egyptians’ gene pool. These data support the critical role of the critical role of some HLA alleles of class I and II that consequently confirm that successful clearance of HCV infection requires strong CD4+ and CD8+ T cell responses. Also, the data generated from our study may help clinicians to predict the treatment outcome for HCV- seropositive individuals in Egypt. Further investigations in this regard with larger number of HCV patients are recommended. Keywords: HLA, MHC, Hepatitis C virus, Egyptian patients