Dendritic cell ability to direct T helper cells dependent on microbial signals.

2003 MAR 19 - (NewsRx.com & NewsRx.net) -- The ability of murine dendritic cell subsets to direct T helper cell differentiation is dependent on microbial signals.

According to recent research from England, "Dendritic cells (DC) initiate T cell responses and direct the class of T cell immunity through the production of Th-polarizing cytokines. In the mouse, immunization with CD8-alpha+ DC has led to Th1 priming whereas immunization with CD8-alpha- DC has been associated with Th2 induction."

"Here, we use a direct T cell priming assay in vitro to re-examine the Th-directing potential of total DC or purified CD4+ DC, CD8-alpha)DC or CD4- CD8-alpha- (double-negative; DN) DC subsets from mouse spleen," reported Shivanthi P. Manickasingham and collaborators at the Cancer Research UK London Research Institute. "We show that the default Th effector phenotype induced by priming with DC depends on the protocol used for T cell purification, the T cell:antigen-presenting cell ratio and the antigen dose but is only marginally affected by DC subtype. All DC subsets can direct increased Th1 development in response to microbial stimuli known to elicit IL-12 production. Similarly, all subsets can suppress Th1 development and allow Th2 cells to expand upon ...