HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 IGA ANTIBODY IN BREAST-MILK AND SERUM

Breast-feeding plays a potentially significant role in mother to child transmission of human immunodeficiency virus type 1 (HIV-1). The addi tional transmission risk attributable to breast-feeding and the factor s that enhance or inhibit transmission are presently unknown. One mech anism by which breast milk might inhibit HIV-1 transmission is the pre sence of specific antibodies directed against HIV-1 in breast milk of seropositive mothers. In this study serum and breast milk samples from women in Nairobi, Kenya, were tested to determine the prevalence of H IV-1 IgA antibodies. A Western blot test developed in our laboratory w as used to detect anti-HIV-1 immunoglobulin A in serum and anti-HIV-1 secretory IgA (sIgA) in breast milk. Ninety-four percent of 63 HIV-1 s eropositive women had anti-HIV-1 IgA in serum and 59% had anti-HIV-1 s IgA in their breast milk. No significant associations with maternal ch aracteristics or serum anti-HIV-1 IgA or IgG banding patterns and the presence of anti-HIV-1 sIgA in breast milk were found. No protective e ffect of anti-HIV-1 sIgA was seen regarding mother to child transmissi on; however, further studies are necessary to determine the effect of these antibodies in maternal sera or in breast milk on the efficacy of HIV-1 transmission.