FIG. 4.

(A) RT-PCR analysis of 10⁶ KSHV/HHV8-infected keratinocytes after treatment with TPA for 48 h. Primers are specific for ORF 26, a late lytic gene encoding a capsid protein. Lanes: 1 and 3, two different cultures infected in parallel and TPA induced; 2 and 4, the same cultures without TPA induction; 5, uninfected keratinocytes; 6 to 10, the same samples without reverse transcription; 11, positive control (BC-3 cells). (B) PCR analysis to confirm the release of viral progeny in the supernatants of TPA-induced keratinocytes. Viral DNA was amplified with KS330 primers. Lanes: 1 and 2, supernatants from two parallel cultures infected and TPA induced; 3 and 4, supernatants from uninfected keratinocytes; 5, primers with no template; 6, positive control (BC-3 cells). (C) Serial transmission. RT-PCR analysis of HUVECs infected with KSHV/HHV8 particles obtained from TPA-stimulated keratinocytes. DNA was amplified with primers specific for v-cyclin. Lanes: 1, KSHV/HHV8-infected HUVECs; 2, control with no RT; 3, primers with no template; 4, positive control (BC-3 cells).