Human T-cell leukemia virus specific antigens.

Type I and type II human T-cell leukemia viruses (HTLV) contain in their genomes three structural genes, gag, pol, and env and a putative transforming gene, lor. Using a living cell membrane immunofluorescence assay, antibodies to surface-expressed env gene products of HTLV-MA have been detected in healthy carriers living in the HTLV-I endemic areas, and in patients with adult T-cell leukemia/lymphoma (ATLL). Similar antibody reactivities were detected in patient MO, from whom HTLV-II was first isolated, and in a proportion of patients with acquired immune deficiency syndrome (AIDS). Amino acid sequence homology between env gene products of HTLV-I and HTLV-II provides the molecular basis for the observed serological crossreactivity. Detection of HTLV-specific antibody in a proportion of AIDS patients suggested that agents related to HTLV-I may be the etiological cause of AIDS. Several lines of evidence have now suggested that HTLV-III is the etiological agent of AIDS. Flanked by the env gene and 3' long terminal repeat (LTR) is a region originally described by Seiki et al. as "X." A 42 kdalton and a 38 kdalton product have been detected in HTLV-I and HTLV-II transformed cells, respectively. These two proteins appear to be translated from a long open reading (lor) frame in the X region, and from a yet to be defined region upstream to the lor gene. The identification of lor products provides direct evidence for the presence of previously unidentified functional genes in HTLV-I and HTLV-II.(ABSTRACT TRUNCATED AT 250 WORDS)