Tumorigenicity of PEL cells and their EBV-converted sublines in SCID mice. (A) The SCID mice were subcutaneously injected with BC-3 and its EBV convertant. The mice were killed at the seventh week after inoculation. Note the highly vascularized tumor growth of BC-3 GFPEBV cl-6, whereas the mouse inoculated with the uninfected BC-3 is tumor free. The left and the right panels show the same mouse. (B) Kinetics of tumor growth in SCID mice. Summary of the rate of tumor growth in mice inoculated with parental BC-3 and BC-3 GFPEBV cl-6 and cl-10 and CRO-AP/6 and CRO-AP/6 GFPEBV cl-1. Two different doses of both the parental CRO-AP/6 and EBV-infected cl-1 were tested. The mean tumor load was calculated by dividing the sum of tumor diameters in all mice by the total number inoculated. Mice were kept under observation between 4 and 8 weeks.