FIG. 3.

Presence of viral DNA in tumor cell lines from the thymus and the axillar lymph nodes. Virus DNA was demonstrated in ex vivo T-cell lines from all animals. Whereas the wild-type (wt) control animals showed evidence for the presence of both virus genes analyzed, the deletion was confirmed in the animals which had received mutant viruses without ie14/vsag (Δ14). C, negative control; T, cell line from the thymus; A, cell line derived from the axillar lymph node. The sizes of marker-DNA fragments are given on the left.