We found that the numbers of circulating IL-10+ Bregs and the levels of serum IL-10 were positively correlated with the concentrations of serum HBV DNA and ALT in the HBeAg− CHB patients and also positively with the concentrations of serum ALT, AST and serum HCV RNA in the CHC patients. This evidence concerns the gene IL10 and cryohydrocytosis.