Scarcity or Absence of Humoral Immune Responses in the Plasma and Cervicovaginal Lavage Fluids of Heavily HIV-1-Exposed But Persistently Seronegative Women
Abstrakt
To address an existing controversy concerning the presence of HIV-1-specific antibodies of the IgA isotype in the female genital tract secretions of highly-exposed but persistently seronegative (HEPSN) women, 41 samples of plasma and cervicovaginal lavage (CVL) fluid were distributed to six laboratories for their blinded evaluation using ELISA with 10 different HIV-1 antigens, chemiluminescence-enhanced Western blots (ECL-WB), and virus neutralization. HIV-specific IgG or IgA antibodies in plasma samples from HEPSN women were absent or detectable only at low levels.
In CVL, 11/41 samples displayed low levels of reactivity in ELISA against certain antigens. However, only one sample was positive in two of five laboratories.
All but one CVL sample yielded negative results when analyzed by ECL-WB. Viral neutralizing activity was either absent or inconsistently detected in plasma and CVL.
Plasma and CVL samples from 26 HIV-1-infected women were used as positive controls.