Detection of herpesvirus DNA by PCR and of EBV-specific RNA by in situ hybridization in tissues of animal J94356. (A) Southern blot of PCR products using probe p536. Detection of 536-bp and 236-bp DNA fragments in tissues from animal J94356 by PCR using primer pairs DFASA/GDTD1B (top) and VYGA/GDTD1B (bottom) at 2 time points. Lanes 1 and 2, PCR results on DNA obtained from noncultured PBMC and affected skin approximately 7 weeks before death (1996). Lanes 3 through 8, PCR products on DNA obtained from animal J94356 at time of necropsy (time 0). Lane 3, PBMC, noncultured; lane 4, affected skin; lane 5, lymph node; lane 6, muscle; lane 7, normal skin. Lane 8, negative control (DNA from normal human PBMC). EBV EBER in situ hybridization performed on sections of affected skin biopsy at low (B) and high (C) magnification. A large number of cells expressing EBV EBER RNA are found infiltrating the dermis and epidermis in the lymphomatous animal.