EBV typing of virus-infected patient peripheral blood and lymphoma tissues. DNA, extracted from CD4⁺ peripheral blood T cells and lymphoma specimens (from distinct lymph nodes) of patient 1, from a lymphoma specimen (spleen) of patient 2, and from control cell lines, was subjected to PCR amplification with specific probes. The EBNA-2 primers were designed to distinguish type-1 and type-2 EBV; the LMP primers were designed to distinguish full length from deleted LMP-1 gene.