Relation between HBV genotypes and cellular immunity of patients with chronic hepatitis B.

Objective To explore relation between genotype of HBV and cellular immunity of patients with chronic hepatitis B and its clinical significance.Methods HBV genotypes of 108 CHB patients were determined by PCR microplate nuclear acid hybridization-ELISA,T cell subgroups(CD3 +,CD4 +,CD8 +,CD4 +/CD8 + ratio),non-specific CTL,helper T cells(Th)1,Th 2 and natural killer(NK) cells were examined by flow cytometry,of whom 55 CHB patients with positive human leukocyte antigen(HLA) A 2 were tested for HBV specific CTL.Results In 107 CHB patients,59 cases had genotype B(54.6 %),48 cases had genotype C(44.4 %) and 1 case had mixed type of B and C(0.9 %).In 55 cases with HLA-A 2 positive(51.4 %),27 were genotype C,28 were genotype B,HBeAg positive rate was higher than that with genotype B(75.0% vs 49.2 %)(P 0.01).HBV DNA titer was higher than those with genotype B(6.12 ± 0.81) log 10 copies/ml vs(5.02 ± 0.61) log 10 copies/ml(P 0.01).HBV specific CTL of genotype C was lower than that of genotype B(0.21 ± 0.06) % vs(0.39 ± 0.12) %(P 0.01).For patients infected with genotype C,non-specific CTL was higher than those with genotype B(19.84 ± 6.17) % vs(16.81 ± 3.56) %(P 0.01).ALT was higher than that with genotype B(505.12 ± 312.91) U/L vs(222.11 ± 205.16) U/L(P 0.01),TBIL was higher than that with genotype B(45.71 ± 41.21) μmol/L vs(28.18 ± 15.12) μmol/L(P 0.05).Conclusion Compared with CHB patients infected with genotype B,HBV specific CTL was lower in patients infected with genotype C,resulting in higher HBV DNA level,HBeAg positive rate was also higher than that in patients with genotype B.So,liver function damage of patients with genotype C was more serious.In addition,the reason for that was probably related to higher non-specific CTL in patients with genotype C than that in patients with genotype B.