Mother-to-child transmission of human T-cell lymphotropic virus type I (HTLV-1) in Jamaica: association with antibodies to envelope glycoprotein (gp46) epitopes

ABSTRACT

To study mother-to-child transmission of HTLV-I in Jamaica, we screen antenatal patients in Kingston, Jamaica, from 1983 to 1985. Of 2,329 women, 81 (3.5 percent) were HTLV-I seropositive. Two to three years later, 36 seropositive mothers were recontacted, and blood was drawn from them and their children. All sera were tested for HTLV-I antibodies, and mother's sera were additionally tested for HTLV-I whole-virus antibody titer, syncytium-inhibition neutralizing antibody liter, and titers to six synthetic peptides from the HTLV-I envelope glycoprotein gp46. Seventeen of 74 (23 percent) [95 percent confidence interval (CI) 15-34 percent] children were seropositive. HTLV-I transmission was associated with breast-feeding duration > 6 months [relative risk (RR) 3.2; CI 0.4-22.1], maternal age > 30 years (RR 2.8; CI 1.0 - 7.8), and higher maternal whole-virus antibody titer (RR 3.3; CI 1.3 - 8.5). After controlling for higher whole-virus antibody titer, transmission remained associated with higher titer of neutralizing antibody and higher titer of antibody to the peptide sp4al, corresponding to amino acids 196 - 209 of the gp46 envelope glycoprotein. We conclude that mother-to-child transmission of HTLV-I in Jamaica is associated with longer duration of breast-feeding, older age, and higher HTLV-I antibody titer, in particular to a certain immunogenic portion of the gp46 envelope glycoprotein.(AU)