Since no further progress was achieved, in order to improve the long-term organ transplantation outcome, the immune tolerance appears as an interesting therapeutic goal. Dendritic cells (DCs) are specialized cells participating in the homeostasis of the immune response. Moreover, subsets of DCs, identified in humans, appear to have their respective competences in immune response modulation. Our objective is to purify from PBMC or to differentiate DC subsets from monocytes using several strategies and evaluate their IL10 secretion.
CD14+ cells were purified from peripheral blood mononuclear cell (PBMC) by affinity beads and cultured with cytokines up to 7 days. The pDCs were purified with anti-BDCA-2 beads from PBMC fraction enriched by Percoll® gradient. The moDCs, pDCs and moLCs subsets were analyzed by phenotype labelling and FACS analyses and IL10 secretion measured by ELISA.
The moDCs were characterized by the CD209 expression and a lower expression of CD1a markers. Expression of CD207 and CD1a markers characterized moLCs and CD123+/BDCA-2+ pDCs. Variable IL-10 secretions were shown between the three DC subsets, both at basal and activated levels.
As the several DC populations studied have different capacities of IL-10 synthesis, they might play, among others, distinct roles in the induction of immune tolerance.