B cell depletion in HIV-1 subtype A infected Ugandan adults: relationship to CD4 T cell count, viral load and humoral immune responses

PLoS One. 2011;6(8):e22653. doi: 10.1371/journal.pone.0022653. Epub 2011 Aug 23.

Abstract

To better understand the nature of B cell dysfunctions in subjects infected with HIV-1 subtype A, a rural cohort of 50 treatment-naïve Ugandan patients chronically infected with HIV-1 subtype A was studied, and the relationship between B cell depletion and HIV disease was assessed. B cell absolute counts were found to be significantly lower in HIV-1+ patients, when compared to community matched negative controls (p<0.0001). HIV-1-infected patients displayed variable functional and binding antibody titers that showed no correlation with viral load or CD4+ T cell count. However, B cell absolute counts were found to correlate inversely with neutralizing antibody (NAb) titers against subtype A (p = 0.05) and subtype CRF02_AG (p = 0.02) viruses. A positive correlation was observed between subtype A gp120 binding antibody titers and NAb breadth (p = 0.02) and mean titer against the 10 viruses (p = 0.0002). In addition, HIV-1 subtype A sera showed preferential neutralization of the 5 subtype A or CRF02_AG pseudoviruses, as compared with 5 pseudoviruses from subtypes B, C or D (p<0.001). These data demonstrate that in patients with chronic HIV-1 subtype A infection, significant B cell depletion can be observed, the degree of which does not appear to be associated with a decrease in functional antibodies. These findings also highlight the potential importance of subtype in the specificity of cross-clade neutralization in HIV-1 infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Antibodies, Neutralizing / immunology
  • Antibody-Dependent Cell Cytotoxicity / immunology
  • B-Lymphocytes / immunology*
  • CD4 Lymphocyte Count
  • Case-Control Studies
  • HIV Envelope Protein gp120 / immunology
  • HIV Infections / blood
  • HIV Infections / immunology*
  • HIV Infections / virology
  • HIV-1 / classification*
  • HIV-1 / immunology*
  • Humans
  • Immunity, Humoral / immunology*
  • Lymphocyte Depletion*
  • Middle Aged
  • Neutralization Tests
  • Recombination, Genetic / genetics
  • T-Lymphocytes, Helper-Inducer / immunology
  • Uganda
  • Viral Load / immunology*
  • Young Adult

Substances

  • Antibodies, Neutralizing
  • HIV Envelope Protein gp120