Subunit vaccine protects Macaca nemestrina (pig-tailed macaque) against simian T-cell lymphotropic virus type I challenge.

Five macaques received two vaccinations consisting of soluble human T-cell lymphotropic virus type I proteins from a cell/serum-free human T-cell lymphotropic virus type I-producing cell line. Five other macaques were vaccine controls. All were challenged with a simian T-cell lymphotropic virus type I-producing cell line. The vaccinated macaques generated a strong serological response to challenge as opposed to the control macaques. Western blot analysis of the sera showed that both groups recognized gag and env proteins, but the vaccinate's sera reacted better to the env proteins. Additionally, the antibody produced by both groups had antibody-dependent, complement-mediated cytotoxic activity toward both human and simian T-cell lymphotropic virus type I-infected target cells. The responses of lymphocytes and neutrophils, as measured by lymphocyte blast transformation and chemiluminescence response, respectively, showed no apparent difference between the vaccinates and controls. Testing for reverse transcriptase in lymphocyte supernatants revealed that the controls contained reverse transcriptase activity, while the vaccinates remained negative. The data presented here demonstrate that the vaccine was successful in protecting Macaca nemestrina from simian T-cell lymphotropic virus type I infection.

Chronic fatal disease in gorillas seropositive for simian T-lymphotropic virus I antibodies.

Sera from 10 gorillas were tested by indirect immunofluorescent antibody assay, Western blotting and ELISA to Human T-lymphotropic viruses for cross-reacting with antibodies to Simian T-lymphotropic virus I (STLV-I). Four were antibody positive. Of the 4 seropositive gorillas, one has remained healthy, while 3 have died with similar disease problems as reconstructed from clinical records. It is not known whether a causal relationship exists between these diseases and STLV-I retrovirus infection.