Simian retrovirus D serogroup 1 has a broad cellular tropism for lymphoid and nonlymphoid cells.
Simian acquired immunodeficiency syndrome is a fatal immunosuppressive disease caused by type D retroviruses such as simian acquired immunodeficiency syndrome retrovirus type 1 (SRV-1). The disease is characterized by generalized lymphadenopathy, opportunistic infections, and lymphoid depletion with defects in both humoral and cell-mediated immunity. To understand how SRV-1 infection relates to the immune defect, we studied in vivo-infected lymphocytes from SRV-1-positive macaques with and without clinical signs of immunosuppressive disease. B and T helper/inducer and T suppressor/cytotoxic lymphocytes were purified by panning or by flow cytometry. Neutrophils were purified by dextran sedimentation, and platelets were purified by low-speed centrifugation. In vitro infection studies were also done with HUT78, H9, K562, rhesus lung fibroblast, rhesus monkey kidney, and bat lung cells. SRV-1 in lymphocytes or culture supernatants was detected by the induction of syncytia in cocultivated Raji cells and was confirmed by immunofluorescence, electron microscopy, or reverse transcriptase assay. We found that B and T helper/inducer lymphocytes were infected in all animals tested. The number of infected T suppressor/cytotoxic cells was generally lower than that of the other cell subsets, and not all animals in this subset had SRV-1 infections. All other cells exposed in vitro to SRV-1, except bat lung cells, were able to be infected. These findings show that SRV-1 has a broad cell tropism for lymphoid and nonlymphoid cell types.
Maul
D H
DH
California Primate Research Center, University of California, Davis 95616.
Zaiss
C P
CP
MacKenzie
M R
MR
Shiigi
S M
SM
Marx
P A
PA
Gardner
M B
MB
D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology / Q000662:veterinary*; D000818:Animals; D000917:Antibody Formation; D002460:Cell Line; D005260:Female; D005434:Flow Cytometry; D007111:Immunity, Cellular; D008253:Macaca mulatta; D008297:Male; D008992:Monkey Diseases / Q000276:immunology* / Q000382:microbiology; D012190:Retroviridae / Q000472:pathogenicity*; D006377:T-Lymphocytes, Helper-Inducer / Q000382:microbiology; D050378:T-Lymphocytes, Regulatory / Q000382:microbiology