FIG. 5.

(A). Splenic enlargement (tumor development) typical of leukemic Mov14/+ mice is delayed in Gag-SN-expressing Mov14/+ animals. The spleen sizes of mice from seven litters resulting from a Mov14/Mov14 × gag-SN/+ cross were monitored by magnetic resonance imaging. As soon as one or more animals in the litter developed enlarged spleens, the relevant litter was sacrificed, and all spleens were weighed. Spleen weights of gag-SN/+, Mov14/+ mice (red triangles, n = 15) were compared with those of nontransgenic Mov14/+ littermates (black circles, n = 16) in a scatter plot. Mean spleen weights of gag-SN/+, Mov14/+ mice (232 mg) are reduced by 61% (P = 0.012) relative to their singly transgenic littermates (599 mg). (B) Marked splenomegaly in a singly transgenic Mov14/+ mouse that developed a T-cell lymphoma (1,300 mg [right]), compared with that in the spleen of an age-matched Mov14/+ littermate expressing the antiviral fusion protein (87 mg [left]).