Cross-clade HIV-1-specific neutralizing IgA in mucosal and systemic compartments of HIV-1-exposed, persistently seronegative subjects

J Acquir Immune Defic Syndr. 2002 Aug 1;30(4):413-20. doi: 10.1097/00042560-200208010-00007.


There is an urgent need for a universally effective HIV-1 vaccine, but whether a vaccine will be able to protect against HIV-1 of different clades is a significant concern. IgA from HIV-1-exposed, persistently seronegative (HEPS) subjects has been shown to neutralize HIV-1 and to block epithelial HIV-1 transcytosis, and it may target novel HIV-1 epitopes. We have tested the ability of plasma and mucosal IgA purified from HEPS subjects to neutralize HIV-1 primary isolates of different viral clades and phenotypes. IgA from two groups of HEPS subjects was tested: sex workers from Nairobi, Kenya, where clades A and D predominate, and the heterosexual partners of individuals infected by clade B virus. HIV-1-infected and low-risk uninfected individuals were included as controls. IgA purified from the blood, genital tract, and saliva of most HEPS sex workers demonstrated significant cross-clade HIV-1 neutralization, whereas a more clade-restricted pattern of neutralization was found in partners of clade B-infected individuals. IgA purified from HIV-1-infected individuals also mediated cross-clade neutralization, whereas IgA from uninfected controls lacked neutralizing activity. In conclusion, mucosal and plasma IgA from HEPS subjects neutralizes HIV-1 of different clades. This ability to induce HIV-1-specific systemic and mucosal IgA may be an important feature of an effective prophylactic HIV-1 vaccine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AIDS Vaccines / immunology
  • Case-Control Studies
  • Cross Reactions
  • Female
  • HIV Antibodies / metabolism*
  • HIV Envelope Protein gp160 / immunology
  • HIV Infections / immunology
  • HIV Infections / prevention & control
  • HIV Infections / transmission
  • HIV Seronegativity / immunology*
  • HIV-1 / classification
  • HIV-1 / immunology*
  • Heterosexuality
  • Humans
  • Immunity, Mucosal
  • Immunoglobulin A / metabolism*
  • Immunoglobulin A, Secretory / metabolism
  • Kenya
  • Male
  • Neutralization Tests
  • Recombinant Proteins / immunology
  • Saliva / immunology
  • Sex Work
  • Sexual Partners


  • AIDS Vaccines
  • HIV Antibodies
  • HIV Envelope Protein gp160
  • Immunoglobulin A
  • Immunoglobulin A, Secretory
  • Recombinant Proteins