No abstract

Background and ObjectiveThe incidence of invasive pneumococcal disease among HIV-infected persons has declined in the post HAART era. Changes in the humoral immune responses have been implicated in this change. It has already been shown that HAART is associated with a decline in BAL total IgG and IgM concentrations and a decrease in BAL pneumococcal-specific IgG concentrations. We measured total and pneumococcal-specific IgA concentrations in BAL of 24 HIV-infected patients before and at 4 and 24 weeks after initiation of HAART, anticipating a similar response.MethodsBAL pneumococcal-specific IgA levels were measured using ELISA. The IgA concentrations were corrected for dilution by determining epithelial lining fluid (ELF) using the urea dilution technique.ResultsData expressed as mean ± SEM μg IgA/mL ELF (*p value ≥ .05). Total and pneumococcal-specific IgA levels did not change after initiation of HAART. No change was detected in the levels of pneumococcal-specific IgA when expressed as a percentage of total IgA. No significant correlation was found between BAL IL-6 and IgA concentration or BAL percentage lymphocytes and IgA concentrations.ConclusionHAART is not associated with significant changes in total or pneumococcal-specific IgA concentrations in the distal respiratory tract. We speculate that this reflects the more dominant role of IgG in protection of the alveolar space against bacterial pathogens.