[Cellular immunity induced by CD40 ligand-activated dendritic cells in CEA transgenic mice].

Objective: To investigate the role of CD40 ligand (CD40L) in dendritic cells (DC) of CEA transgenic mice and to evaluate the specific cellular immunity induced by activated DC.

Methods: Bone marrow cells of the CEA transgenic mice were used to generate immature dendritic cells under the condition of GM-CSF and IL-4. CD40L was added to activate dendritic cells into mature phenotype. Dendritic cells cancer vaccine was pulsed with CEA526-533 peptide which made the vaccine specific for cancer immunity. The immunophenotype molecules were identified by flow cytometry. The cytokines produced by cells were determined by ELISA. T cells proliferation was measured by (3)H-thymidine essays.

Results: Immunophenotype molecules expressions of CD40L-activated dendritic cells were significantly higher than those in control group. IL-12 secretion by CD40L-activated dendritic cells was (937.81+/-51.99) pg/10(6) DC, significantly higher than that in control group [(83.06+/-8.58) pg/10(6) DC, P<0.01]. CD8(+) T cells proliferation induced by CD40 L-activated dendritic cells was stronger as compared to control group (P<0.05), and the secretion of IFN-gamma was(33.900+/-4.550) ng/L, significantly higher than that in control group [(5.226+/-0.460) ng/L, P<0.01]. Splenocytes proliferation induced by CD40 L-activated dendritic cells was stronger as compared to control group (P<0.01), and the secretion of IFN-gamma was (69.802+/-11.407) ng/L, significantly higher than that in control group [(2.912+/-0.562) ng/L, P<0.01].

Conclusion: The method of using CD40L to stimulate bone marrow-delivered dendritic cells promotes the maturation and activation of dendritic cells, which enhances the cellular immunity in CEA transgenic mice.