[In vitro effect on the differentiation and maturation of monocyte-derived dendritic cells by mannan-binding lectin]

To explore the effect of mannan-binding lectin (MBL) on the differentiation and maturation of human peripheral blood monocyte-derived dendritic cells (MoDCs).

After MoDCs was stimulated with human natural MBL, MoDC's morphology was observed under inverted microscope and the expressions of CD1a, CD83, CD40, CD80, CD86 and HLA-DR on MoDCs were analyzed by FACS. The ability of MoDCs to stimulate the proliferation of allogenic T cells was detected by (3)H-TdR incorporation. The ability of MoDCs to up-take antigens was evaluated by zymosan granule phagocytosis test. The levels of IL-12 and TNF-alpha in the culture supernatant of MoDCs were determined by ELISA.

The expressions of CD1a, CD83, CD40, CD80, CD86 and HLA-DR on the MoDCs were up-regulated by MBL. The ability of MoDCs to up-take zymosan granules decreased and the proliferation of native T cells induced by MoDCs was enhanced. MBL stimulated the production of IL-12 by MoDCs, but had no such effect on TNF-alpha secretion.

MBL can induce differentiation and maturation of DCs in vitro, suggesting that MBL possibly participate in the adaptive immune response through modulation of functions of DCs.