Microarray analyses of lymph node dendritic cells (DCs) stimulated in vitro with papain or LPS

T helper type 2 (Th2) responses are induced by protease allergens and helminthes. However the molecular mechanisms that initiate Th2 responses are poorly understood. To obtain insight into this mechanism, we performed a microarray analysis of lymph node DCs stimulated in vitro with the protease allergen papain, or with LPS, a Th1 inducing stimulus. Key words: Th2 response, LPS, dendritic cells, Papain CD11c+ DCs were isolated from the lymph nodes of C57BL/6 mice, and cultured in vitro (1x106 DCs per ml) with 500 3T3-CD40L fibroblasts, either alone, or in the presence of papain (25 µg/ml) or LPS (1 µg/ml). 4h and 17h later, the cells were harvested and RNA isolated and processed for microarray analyses. RNA was extracted and processed from freshly isolated LN DCs. For a given time point, the expression profile of DCs treated with papain or LPS, were compared to that of untreated DCs