An in vitro assay for T cell immunity to malaria in mice.

After infection with a nonlethal strain of murine malaria (17XNL Plasmodium berghei yoelli), BALB/c mice are then resistant to a lethal strain (17XL P.b. yoelli). BALB/c mice were infected with 17XNL, anc challenged 3 weeks later, after clearing their parasitemias, with 17XL. Three weeks thereafter, spleen cells from such immune animals were used to define an early peaking T-dependent (anti-theta sensitive) antigen-specific proliferative response when incubated in vitro with 17XL infected RBC, or a saline soluble 17XL antigen preparation. T dependent responsiveness of spleen cells from uninoculated control animals to the 17XL antigen preparation was also observed, but demonstrated a much different (delayed) kinetics from that observed with immune cells.