Optimal culture conditions for in vitro antigen-induced proliferation of rat lymph node cells.

Popliteal and inguinal lymph node cells (LNC) from rats immunized with ovalbumin (OA) in Freund's adjuvant, were cultured with OA for 4 days in a variety of serum-supplemented media. Incorporation of [3H]thymidine into [3H]DNA was assessed as an index of antigen-induced lymphoproliferation. Optimal conditions for proliferation were found to comprise culture in flat-bottomed vessels, in the presence of RPMI 1640 medium adjusted to rat osmolality (310 mosmoles/kg) containing 5% v/v fresh syngeneic rat serum plus 4 X 10(-4) M 2-mercaptoethanol.