title: Detection of antibodies to trans-activator protein (p40taxI) of human T-cell lymphotropic virus type I by a synthetic peptide-based assay.
abstract: Antibodies to human T-cell lymphotropic virus type I (HTLV-I) trans-activator protein (p40taxI) were determined in serum specimens from individuals infected with HTLV-I (n = 138) and HTLV-II (n = 19). Western blot (immunoblot) analysis using recombinant tax demonstrated the presence of anti-tax antibodies in 96% of patients (25 of 26) with HTLV-I-associated myelopathy, 43% of those (20 of 46) with adult T-cell leukemia, and 61% of asymptomatic HTLV-I blood donors (40 of 66); only one of the HTLV-II specimens reacted with the recombinant tax protein. Synthetic peptides (Tax8(106-125), Tax22(316-335), Tax-23(331-350), and Tax-24(336-353) representing the immunodominant epitopes of p40taxI detected anti-tax antibodies in 66 (48%), 50 (36%), 66 (48%), and 64 (46%) of 138 HTLV-I-positive specimens, respectively. An enzyme immunoassay using an equimolar ratio of these four peptides allowed sensitive detection of anti-tax antibodies in 96% of patients (25 of 26) with HTLV-1-associated myelopathy, 52% of adult T-cell leukemia patients (24 of 46), and 62% of asymptomatic HTLV-1-infected donors (41 of 66). The synthetic peptide-based cocktail assay was HTLV-I specific, since none of the HTLV-II-infected specimens reacted with these peptides. Interestingly, the corresponding regions from the HTLV-II tax protein, Tax8II(106-125), and Tax-22II(312-331) did not react with either HTLV-II or HTLV-I specimens. Thus, a synthetic peptide-based assay composed of immunodominant epitopes located towards the amino terminus and the C terminus of p40taxI provides a reliable and sensitive assay for the detection of anti-tax antibodies in seroepidemiologic studies.
mesh_terms: D000595:Amino Acid Sequence; D016356:Gene Products, tax / Q000235:genetics / Q000276:immunology*; D015481:HTLV-I Antibodies / Q000097:blood*; D015490:HTLV-I Infections / Q000276:immunology / Q000821:virology; D006801:Humans; D016056:Immunodominant Epitopes; D007124:Immunoenzyme Techniques; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000235:genetics / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology*
chemical_list: D016356:Gene Products, tax; D015481:HTLV-I Antibodies; D016056:Immunodominant Epitopes; D010455:Peptides; D011994:Recombinant Proteins