Property and implication of dendritic cells from peripheral blood monocytes in patients with persistent hepatitis B virus infection.

Objective To identify the property and implications of dendritic cells of peripheral blood monocytes (PBMC) in patients with persistent HBV infection. Methods The PBMC from 18 patients with persistent HBV infection and 10 healthy subjects were incubated and induced into mature dendritic cells (DC) in the completed medium containing GM CSF、IL 4、FLt3 L and TNF α cytokines. The flow cytometric analysis was employed to detect the expression of surface markers on DC. ELISA test was used to determine the level of interleukin 12 (IL 12) and IL 10 cytokines produced by DCs. The stimulatory capacity of DC were also determined in allogenic mixed leukocyte reaction (MLR). Results A typical morphology of DCs was observed when the PBMCs from healthy subjects and HBV infected patients were induced for 6 7 day in vitro incubation, but there were some significant differences of DCs as follows: (1) the proliferation ability and number of DCs significantly decreased, in particular, the expression levels of HLA DR,CD80(B7 1),CD86(B7 2) and CD1α on DC surface were simultaneously much lower in patients compared to healthy subjects ( P 0.001); (2) the stimulating capa city in MLR and secretion of IL 12 of DC were lower, but the levels of NO, which represented the factor relating to liver pathologic damage, were significantly increased in patients compared with healthy individuals ( P 0.05). Conclusions The patients with persistent HBV infection have the defective function and immature phenotype of dendritic cells, resulting in inability of efficient presentation of HBV antigens to host immune system for the clearance of HBV and leading to the persistent HBV infection.