SEROLOGICAL AND NUCLEIC-ACID ANALYSES FOR HIV AND HTLV INFECTION ON ARCHIVAL HUMAN PLASMA SAMPLES FROM ZAIRE

In order to better understand the genomic diversity and molecular phyl ogeny of the human retroviruses, the plasmas from 250 Zairean patients collected in 1969 were tested for antibodies to human T-cell lymphoma and human immunodeficiency viruses (HTLV or HIV) using ELISA and conf irmatory Western blots and for viral nucleic acids by reverse transcri ptase-directed PCR (RT-PCR). Interestingly, none of the patients was c onfirmed positive for HIV, even though this region is now endemic for HIV-1. However, 74 (30%) and 3 (1%) of the samples were positive for a ntibodies to HTLV-I and II, respectively. Forty-four of 74 (59%) Weste rn blot-positive Zairean samples were RT-PCR positive for HTLV-I, whil e 1 of 3 (33%) of HTLV-II-seropositive samples was RT-PCR positive. On the contrary, none of the Western blot-negative or indeterminate samp les were RT-PCR positive for either HTLV-I or HTLV-II, We have cloned and sequenced 140 bp of the pol gene flanked by SK110/SK111 from 8 HTL V-I- and 1 HTLV-II-positive archival samples from Zaire, The HTLV-I is olates from Zaire cluster together as a phylogenetic group, diverging from the prototype Japanese HTLV-I (ATK) by a range of 1.4 to 3.6%. Th eir close homology to some African STLV-I isolates suggests relatively recent interspecies transmission. The Zairean HTLV-II isolate is clos ely grouped with the HTLV-II substrain of isolates found in Paleo-Amer indians of the New World, making it unlikely that it represents an end emic African strain. (C) 1994 Academic Press, Inc