Role of complement component C4 in treatment response and disease progression in chronic hepatitis C patients.

The basis of hepatitis C virus (HCV) evasion of immune system and its response to treatment is still elusive. There have been studies where the level of C4 has been found to be associated with HCV persistence and disease progression. This study aims to find out relationship between levels of C4 in serum, and its functional SNPs with response to treatment. The study included 84 patients with CHC who received treatment and 75 healthy controls. C4 expression, both at mRNA and protein level, was estimated by Real time and ELISA respectively. Its functional SNP's genotyped by AS-PCR. The mean ± SD baseline C4 levels between the disease and healthy cases was significantly different (1075.74 ± 65.25 vs 1593 ± 24.55 ng/mL, P < 0.001). The mean ± SD baseline C4 levels of CC, GC and GG genotype of rs2857009 in the healthy group were 1540.97 ± 7.87, 1599.53 ± 11.75 and 1604.86 ± 10.79 ng/mL, respectively (P < 0.001), whereas the levels in the CHC group were 1022.81 ± 32.95, 1058.19 ± 55.02 and 1150.26 ± 14.64 ng/mL, respectively (P < 0.001). CC genotype resulted in decreased C4 mRNA levels compared to GG genotype in healthy group (3.81-fold) and CHC group (1.4-fold). The CC genotype of rs2857009 is associated with reduced expression of C4, both at mRNA and protein level. The C4 serum level at baseline and total protein were found to be independent predictors for treatment response. New predictive score using the above factors, a value of ≥ 0.542 was found to predict positive response to treatment. Increased age, rs2857009 SNP and HCV genotype were associated with disease progression.

rs2230201 polymorphism may dictate complement C3 levels and response to treatment in chronic hepatitis C patients.

The basis of response of chronic hepatitis C (CHC) patients to treatment is still unclear, and there may be many other factors which influence treatment outcome other than the existing ones. The serum concentration of C3 closely reflects the total complement activity, and individuals affected by C3 deficiency suffer from recurrent pyogenic infections. This study aims to find out relationship between levels of C3 in serum and its functional SNPs with response to treatment. The study included 132 CHC patients of which 48 received Pegylated IFN+Ribavirin and 81 controls. C3 levels and its three known functional SNP's genotyped by ELISA and SSP PCR, respectively. C3 Level of the healthy group was significantly higher (88.5 ± 19 mg/dL) when compared to CHC group (56 ± 18 mg/dL; P < 0.001). Thirty-three of 36 responders were rs2230201 CC genotype carriers, whereas 9 of 12 nonresponders were non-CC genotype. The 'C' allele of rs2230201 was found to be associated with increased serum C3 levels when compared to other genotypes in healthy group, whereas CT genotype was associated with lowered serum C3 in CHC group. A serum C3 value of <53 mg/dL was predictive of SVR with sensitivity 63.89% and specificity 66.67%. The study supports the observation that rs2230201 'C' allele is associated with increase of serum C3 levels when compared to 'T' allele which may confer advantage in attaining SVR when present in homozygous condition. The study suggests that patients with serum C3 value <53 mg/dL and non-CC genotypes may not respond to treatment.