The search for human infection with simian type D retroviruses

Evidence has recently been presented for an infection with a simian type D retrovirus in a patient with AIDS and lymphoma. We tested for simian type D infection in three groups of subjects: 375 patients with lymphoproliferative diseases (255 non-Hodgkin's, 88 Hodgkin's, and 32 chronic lymphoproliferative disease), of whom 75 were human immunodeficiency virus (HIV)-1 infected; seven persons with unexplained low CD4 lymphocyte counts with clinical conditions; and 45 blood donors, of whom 37 were human T-lymphocyte virus (HTLV)-I/II seroindeterminate and eight were HTLV-I/II and HIV-1 seronegative. Serum samples were screened for antibodies against simian type D retroviruses by an enzyme immunoassay, and reactive samples were analyzed by Western blotting. None of the samples were seropositive, but eight (five from non-Hodgkin's and three from Hodgkin's lymphoma patients) were seroindeterminate. Polymerase chain reaction analysis of genomic DNA from peripheral blood lymphocytes of all eight of these patients was carried out using simian type D gag generic primers with generic internal oligoprobing. All samples were negative. We conclude that simian type D infection is rare among HIV-infected and noninfected lymphoma patients, persons with unexplained low CD4 counts, and persons with HTLV-seroindeterminate test results.