title: Immunoglobulin G Fc(gamma) receptor expression on polymorphonuclear cells in bronchoalveolar lavage fluid of HIV-infected and HIV-seronegative patients with bacterial pneumonia.
abstract: This study was designed to test the hypothesis that impaired neutrophil function might contribute to the development of bacterial pneumonia in patients with HIV-infection. Numbers of inflammatory cells and immunoglobulin G Fcgamma receptor (IgG FcgammaR) I, II, III levels were investigated in bronchoalveolar lavage (BAL) fluid of HIV-seronegative and HIV-infected patients with bacterial pneumonia. The 99 patients were classified into three groups: I: HIV-seronegative and pneumonia (n = 40); II: HIV-infected and pneumonia (n = 19); III: HIV-seronegative with other pulmonary diseases than pneumonia (n = 40). The results of groups I and II, II and III, and I and III were compared. The percentage of alveolar macrophages was significantly lower (group II vs. III: p = 0.005, group I vs. III: p = 0.001), that of neutrophils increased significantly in patients with pneumonia (group II vs. III: p = 0.02, group I vs. III: p = 0.01). Lymphocytes differed only between groups I and III (p = 0.04). Although only the expression of FcgammaRI was significantly higher in HIV-seronegative pneumonia patients compared to those without pneumonia (p = 0.01), the mean expression of all three receptors was lower in the HIV-infected group, with that of FcgammaRI approaching statistical significance. This report provides first evidence that altered FcgammaR expression on BAL neutrophils might contribute to the increased susceptibility of HIV-infected patients to bacterial pneumonia.
authors.affiliation: 2nd Medical Department, SMZ Baumgartner Höhe, Vienna, Austria. christine.armbruster@gmx.at
authors.forename: Christine
authors.initials: C
authors.lastname: Armbruster
authors.forename: Walter
authors.initials: W
authors.lastname: Krugluger
authors.forename: Monika
authors.initials: M
authors.lastname: Huber
authors.forename: Kriwanek
authors.initials: K
authors.lastname: Stephan
mesh_terms: D000328:Adult; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D015658:HIV Infections / Q000276:immunology*; D018023:HIV Seronegativity / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000276:immunology*; D018410:Pneumonia, Bacterial / Q000276:immunology*; D017452:Receptors, IgG / Q000096:biosynthesis* / Q000276:immunology
chemical_list: D017452:Receptors, IgG