Plasmodium berghei adoptive transfer and immunosuppression of immunity in allogenic neonates.

Outbred female rats were hyperimmunized with Plasmodium berghei and mated to produce progeny. Spleen cells from the immunized rats and from normal control mothers were adoptively transferred to their 48 hr old neonates. Some neonates from immune mothers were fostered to normal mothers and vice versa. Weanling rats were challenged 35 days after birth with Plasmodium berghei; immune and normal litters which had not received cells were also challenged at the same time. Rats which had received immune spleen cells from their mothers but were fostered on to non-immune mothers showed significantly lower parasitaemias and higher fluorescent antibody titres than any other combination of cell transfer and maternal milk. GVH reaction was minimal. These results suggest that the immune response to P. berghei was suppressed in the presence of passively transferred maternal antibody.