Collection of lymph-borne dendritic cells in the rat.

Dendritic cells (DCs) are crucial in immune induction. Not only do they collect antigens in peripheral tissues, and transport and process them for presentation to lymphocytes in draining lymph nodes, but they also regulate the immune response by modulating T-cell differentiation. Intestinal and hepatic DCs migrating in lymph can be collected from rats under near-physiological conditions. Initially, the mesenteric or celiac lymph nodes are removed from young rats (30 min). The afferent and efferent lymph vessels subsequently heal, permitting DCs to enter the thoracic duct. After at least 6 wk, the duct is cannulated (40 min). Lymph can be collected for up to 48 h. DCs can subsequently be identified, enriched and sorted to high degrees of purity. This two-stage technique generates large numbers of immunologically relevant DCs under near-physiological conditions. Lymph collection requires 2-3 h per animal over 6 wk.