CHARACTERIZATION OF INFECTIOUS TYPE-D RETROVIRUS FROM BABOONS

Infectious virus resembling type D simian retrovirus (SRV) was isolate d from Ethiopian baboons (Papio cynocephalus) (SRV-Pc) housed at the U niversity of Washington Regional Primate Research Center. When baboon peripheral blood mononuclear cells (PBMC) or tissues were cocultured w ith the H-9 human T-cell line or the Raji human B-cell line, large mul tinucleated syncytia positive for sRV-2 antigens were observed microsc opically. Immunoblot analysis of purified SRV-Pc from cell culture sup ernatants demonstrated that the viral core and envelope proteins react ed with rabbit anti-SRV-2 serum. Fresh PBMC and cocultured cells were positive by polymerase chain reaction using two different sets of SRV- 2 primers. Preliminary sequence analysis of two separate isolates from portions of the SRV-Pc p27 and gp20 regions revealed homology with SR V-1, SRV-2, and Mason-Pfizer monkey virus. The homologies in the p27 s egment were 91-94% and the homologies in the gp20 segment were 72-75%. (C) 1995 Academic Press, Inc.