Serological cross-reactivity between envelope gene products of type I and type II human T-cell leukemia virus.

Abstract

People exposed to type I human T-cell leukemia virus (HTLV-I) develop antibodies to an antigen at the surface of virus-infected cells, designated human T-cell leukemia virus membrane antigen (HTLV-MA). In an earlier study, we demonstrated that the major component of HTLV-MA is gp6l, a glycoprotein encoded by the HTLV env gene. In the current study, we found that human antibodies that react with HTLV-MA on cells infected with HTLV-I react equally well with HTLV-MA on C3-44/MO, a target cell infected with type II HTLV. A glycoprotein with an approximate size of 67 kDa, gp67, was identified in C3-44/MO using immunoprecipitation and NaDodSO4/PAGE analysis. The positions of serine and cysteine residues were determined in the amino terminus of gp67 by radiolabel sequencing analysis. Comparison with the amino acid sequence deduced from the primary nucleotide sequence of HTLV-IIMo virus reveals that gp67 is also encoded, at least in part, by the env gene. The gp67 of HTLV-IIMo, like the env gene product of HTLV-ICR, gp6l, is recognized both by antibodies from a HTLV-IIMO-infected patient with a variant form of hairy cell leukemia, and by antibodies from patients with HTLV-I-associated adult T-cell leukemia/lymphoma. These results indicate that, despite the divergence between HTLV-I and HTLV-II, the major env gene products of the two types of HTLV are conserved to the degree that they are serologically cross-reactive.

Human monoclonal antibody directed against an envelope glycoprotein of human T-cell leukemia virus type I.

“…These features make the 0.5a antibody an important reagent for studying the natural history and-biology of HTLV-I infections. It has been reported that viruses belonging to the HTLV-I family share some -common nucleotide sequences (24) and antigenic epitopes (1,25). However, the epitope that was recognized by 0.5a is apparently not one in common with the other members of the HTLV family.…”

Antibodies to HTLV-1?2, HIV-1 and HIV-2 in syphilitic patients

“…They were both Italian heterosexual prostitutes, 28 and 58 years-old respectively, and had not travelled abroad. The most surprising finding of our investigation was the unexpectedly high number of HTLV-1-2 antibodies in syphilitic patients and in prostitutes who were seronegative for both HIV-1 and HIV-2, suggesting that HTLV-1-2 infection may occur independently of HIV-1 and HW-2, although considerable antigenic cross-reaction that HTLV-1-2 infection may occur independently of HIV-1 and HIV-2, although considerable antigenic cross-reaction between HTLV-1 and HTLV-2 (11,12,13,14) does take place. We cannot rule out the involvement of other viruses in the observed positivity.…”

“…The data suggest that an additional program for detecting exposure to HTLV-1 have to be undertaken in order to stop the trasmission of this virus. We hope that a new test can be developed for the detection of specific antibodies, which, together with the use of type-specific probes against HTLV-1 and HTLV-2 (13,14), will help determine the real incidence of subjects with these different infections.…”

“…In Africa the HIV-2 retrovirus has recently been isolated from a few patients with AIDS (3). Since transmission of HIVs and HTLVs is similar and closely linked to blood transfusion, infection through needles and sexual promisquity, we decided to investigate the spread of HTLV-1 (or HTLV-2, due to reported cross reactivity [14]), HIV-1 and HIV-2 antibodies in a group of 318 seropositive patients suffering from a c o m m o n venereal disease such as syphilis.…”

Human T Lymphotropic Virus Type 1 SU Residue 195 Plays a Role in Determining the Preferential CD4+T Cell Immortalization/Transformation Tropism

“…The viral envelope is generated as a polyprecursor protein (gp61) comprised of 488 amino acids which is cleaved into the surface domain (SU-gp46) and transmembrane domain (TMgp21) (20,21). SU binds to the cellular receptor(s), and then SU and TM undergo significant conformational remodeling, thereby exposing TM to facilitate membrane fusion and subsequent entry into the cell.…”