Interactive Effects of Immunoglobulin Gamma and Human Leucocyte Antigen Genotypes on Response to Interferon Based Therapy of Hepatitis C Virus.

AIM:We examined the role that immunoglobulin GM 23 and KM allotypes-genetic markers of γ and κ chains, respectively-play in response to treatment of hepatitis C virus (HCV) infection in Egyptian patients. MATERIAL AND METHODS:A total of 120 persons who had responded to HCV treatment and 125 with persistent HCV infection were genotyped for the presence of GM23 and KM determinants. HLA -C genotyping was also done. RESULTS:Association of GM 23+ and KM3 was significantly associated with non response to treatment (P < 0.0001). Individuals who lacked this GM genotype (but were positive for KM1,2 and 3) were likely to respond to treatment (P=0.045). Association of heterozygous GM23 (+/-) with KM 1,2 and 3 or KM3 alone was significantly associated with SVR (P = 0.001) and (P = 0.0001) respectively. Particular combinations of HLA and GM genotypes were associated significantly with the response to HCV treatment. The combination of HLAC2C2 and GM23+ was associated with persistence of infection (P = 0.027) while the association of HLAC2C2 and heterozygous GM23+/- was associated with SVR (P = 0.001). The association of HLAC1C1 and heterozygous GM23+/- was significantly associated with SVR (P = 0.001) and also subjects with HLA C1/C2 and heterozygous GM23+/- were likely to respond to treatment (P = 0.003) while subjects with HLA C1/C2 and GM23+ show tendency to resist to treatment (P = 0.0001). CONCLUSION:Our results didn't support a role for KM allotypes, GM23 allotype plays a role in the persistence of HCV infection in the presence or absence of KM1,3. Interaction between certain GM and HLA-C genotypes may favor adequate response to interferon based therapies.