Dendritic cells (DCs) need activation for the priming of antigen-specific immune responses. Recently activated DCs were described to prime in vitro strong T helper cell type 1 (Th(1)) responses, whereas at later time points, the same cells preferentially prime Th(2) cells [Langenkemp, A. et al., Nat. Immunol. 1: 311-316, 2000]. Because the immune response against @entity5 strongly depends on CTLs of Th(1)-like phenotype (Tc(1)), we verified here whether the kinetics of DCs activation also impacted on in vivo priming of @entity5 -specific CTLs. After pulsing with the CTL epitope @entity41258 (180-188), bone-marrow-derived DCs, exposed to lipopolysaccharide (LPS) for 8 h (8 @entity15734 ), elicited a more powerful Tc(1) response in C57BL/6 @entity19 than did untreated DCs, or DCs exposed to LPS for 48 h (48hDC). Indeed, 8hDCs were the most potent protective and therapeutic vaccine against @entity6844 . Despite a higher expression of MHC and costimulatory molecules by 48hDCs, 8hDCs and 48hDCs showed comparable allostimulatory and migration potential, and susceptibility to CTL-mediated apoptosis. However, 8hDCs exhibited a significantly higher interleukin (IL)-12 production potential. Release of IL-12 was necessary to induce potent @entity19 ) cells, because DCs from @entity12782 (-/-) @entity19 , irrespective of their maturation level, generated low CTL responses, comparable with 48hDCs and 0hDCs from wild-type animals. Our data are relevant for the design of @entity15734 -based vaccines.

Critical impact of the kinetics of dendritic cells activation on the in vivo induction of XXXX -specific T lymphocytes.

@entity12782 :: ('16160(Tax:10090)', 'Gene') :: ['IL-12p40'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'cancer'] @entity19 :: ('10090', 'Species') :: ['mice', 'Tc(1'] @entity41258 :: ('104042(Tax:10090)', 'Gene') :: ['TRP-2'] @entity6844 :: ('MESH:D008546', 'Disease') :: ['B16 melanoma'] @entity15734 :: ('3067', 'Gene') :: ['hDC', 'DC']
@entity5 :: (MESH:D009369,Disease) :: ['tumor']
