Transgenic mice.
Generation of LMP1 mice under the Ig heavy chain promoter and enhancer have been described previously and were maintained as heterozygotes on a Balbc background [26]. LMP1 mice were genotyped by Southern blot and PCR analysis of tail DNA as described previously [26]. Spleen and liver sections were fixed in 4% paraformaldehyde and embedded in paraffin, and 5-μm sections were stained with hematoxylin and eosin for histopathological analysis. Lymphomas were passaged by intraperitoneal injection of 1 × 108 splenocytes into SCID mice and sacrificed upon development of an extended abdomen. Animals were housed in the Association for Assessment and Accreditation for Animal Care–approved animal facility at the University of North Carolina at Chapel Hill. All protocols were approved by the Institutional Animal Care and Use Committee.