Anti-HTLV-I IgG in urine detected by sensitive enzyme immunoassay (immune complex transfer enzyme immunoassay) using a synthetic peptide, Cys-env gp46(188-224), as antigen.

Antibody IgG to human T-cell leukemia virus type I (HTLV-I) in urine was detected by a sensitive enzyme immunoassay (immune complex transfer enzyme immunoassay) using a synthetic peptide, Cys-env gp46(188-224), as antigen, the sensitivity and specificity of which were 100 and 98.5%, respectively, using serum samples. Anti-HTLV-I IgG in urine was reacted simultaneously with 2,4-dinitrophenyl-bovine serum albumin-Cys-env gp46(188-224) conjugate and Cys-env gp46(188-224)-beta-D-galactosidase (Escherichia coli) conjugate. The complex formed, consisting of the three components, was trapped onto polystyrene balls coated with affinity-purified (anti-2,4-dinitrophenyl group) IgG, eluted with epsilon N-2,4-dinitrophenyl-L-lysine and transferred to polystyrene balls coated with affinity-purified (anti-human IgG gamma-chain) IgG. Finally, bound beta-D-galactosidase activity was assayed by fluorometry. Thirty-one urine samples from seropositive subjects and 100 urine samples from seronegative subjects were tested. The sensitivity and specificity were 87 and 100%, respectively, with unconcentrated urine samples and 94 and 100%, respectively, with approximately 10-fold concentrated urine samples. These results were superior to those by the conventional ELISA and gelatin particle agglutination test.