RESUMO
CD40 ligand (CD40L) expressed by activated T cells is shown to induce maturation of immature dendritic cells (DCs) and this maturation is a vital part in DC based tumor immunotherapy. We constructed an expression vector by cloning the extracellular domain of canine CD40L fused to the signal sequence of canine IL-12p40. When PBMCs were incubated with canine granulocyte-macrophage (GM) -CSF and IL-4, expression of CD86 was significantly elevated, but the majority of cells displayed the morphology of immature DCs. Following addition of the expressed canine soluble CD40L (csCD40L) to the DC-inducing culture, the cell morphology shifted to that of mature DCs, and expression of CD80, CD86, MHC class II and CD1a was significantly enhanced. This morphological change and enhancement of expression was observed even when the csCD40L was present only in the second half period of the culture. Furthermore, the csCD40L caused a significant increase in IL-12 production from DCs. These results show that the csCD40L significantly promotes the maturation and activation of canine monocyte derived DCs.
Assuntos
Ligante de CD40/genética , Células Dendríticas/fisiologia , Imunoterapia , Monócitos/citologia , Neoplasias/terapia , Proteínas Recombinantes de Fusão/farmacologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Ligante de CD40/biossíntese , Células Dendríticas/imunologia , Cães , Subunidade p40 da Interleucina-12/biossíntese , Subunidade p40 da Interleucina-12/genética , Dados de Sequência MolecularRESUMO
IL-12 is a cytokine produced by dendritic cells (DC) and activates cytotoxic T cells and NK cells against tumors. We investigated the effect of IL-12 on DC. When peripheral blood monocytes were incubated with canine granulocyte-macrophage (GM)-CSF and IL-4, expression of MHC class II, CD1a, CD80 and CD86 was significantly elevated, but the cell morphology was that of immature DC. By adding canine IL-12 to the DC-inducing culture, expression of CD80 and CD1a was significantly enhanced, and the cell morphology shifted to that of mature DC. T cell stimulation by cultured cells was also significantly enhanced by the presence of IL-12. These results show that IL-12 significantly promotes the maturation and activation of canine DC following the induction of differentiation by GM-CSF and IL-4.
