Study of phenotypes and functions of dendritic cells derived from the peripheral blood mononuclear cells of patients with chronic severe hepatitis B / 中华传染病杂志

ABSTRACT

Objective To understand the immune regulatory function of monocyte-derived dendritic cells (MoDC) in patients with chronic severe hepatitis B (CSHB) and its roles in the severe illness progression of chronic hepatitis B (CHB) by detecting surface phenotype of MoDC and expression level of cytokines in MoDC after polyl C treatment. Methods The peripheral blood mononuclear cells (PBMC) were isolated by Ficoll density gradient separation from 37 patients with CSHB, 20 patients with CHB, and 20 healthy controls (NC). Purified PBMC were acquired using immunomagnetic anti-CD14-beads. Then PBMC were induced to immature dendritic cell (iDC) in vitro. PolyI C was added to induce DC maturation. The mean fluorescence intensity (MFI) of the phenotype marker molecules including HLA-DR, CD83, CD86 and CD80 on surface of iDC and mature DC (mDC) were detected by flow cytometry. The supernatants of MoDC culture were collected at 12,24 and 48 h after polyI C treatment, respectively and the release levels of interleukin (IL)-12, IL-6and tumor necrosis factor (TNF)-α were determined by enzyme linked immunosorbent assay (ELISA). Comparisons among groups were done by single factor analysis of variance and homogeneity of variance was tested. Results There were no significant differences of phenotype marker molecules on cell surface of iDC, including HLA-DR, CD83, CD86 and CD80 in CSHB, CHB and NC groups.However, the expressions of HLA-DR, CD83, CD86 and CD80 on cell surface of mDC in CSHB group were lower than those in CHB and NC groups (F=59.73, 13.95, 34.80 and 73.02, respectively; all P＜0. 05). The secretions of IL-12 at three time points of 12 h, 24 h and 48 h after polyI C treatment in group NC were higher than those in CHB and CSHB groups (F= 151.34, 126.65 and 72.76, respectively; P＜0.05), and peaked at 24 h which were (48.2±7.6), (56.7±11.8) and (97.8±16.2) ng/L, respectively. The secretions of IL-6 at the above three time points were CSHB＞CHB＞NC (F=92.50, 86.89 and 64.57, respectively; all P＜0. 05) and peaked at 12 h which were (1698.3±340.4), (965.8±231.7), (697.8±213.6) ng/L, respectively. The secretions of TNF-αat the above three time points were CSHB＞CHB＞NC (F=58.66, 122.36 and 44.73, respectively;all P＜0. 05) and were (19 672. 7±4214. 7), (9946. 1 ± 2586 5), (6659. 2±955. 8) ng/L,respectively at 24 h after treatment. Conclusions MoDCs of CSHB patients show mature defection and abnormal cytokine secretion. The expression level of IL-12 which mediates cellular immune is low.Meanwhile, the productions of IL-6 and TNF-α which mediate inflammatory response are up-regulated. This may be one of the major factors which lead to exacerbation of liver inflammation and ultimately development of severe hepatitis.