BACKGROUND: Alveolar macrophages (AMs) are more efficient antigen-presenting cells in allergic individuals than in nonatopic subjects. OBJECTIVE: We studied whether this difference may be correlated to increased expression of membrane costimulatory molecules, such as the B7 molecules (CD80 and CD86). METHODS: Eleven subjects with allergic asthma sensitized to Dermatophagoides pteronyssinus and 5 healthy nonatopic volunteers underwent bronchoalveolar lavage, and the costimulatory molecule expression on AMs was evaluated. Peripheral blood T cells, either freshly isolated or as established D pteronyssinus -specific cell lines, were cultured with autologous monocytes or AMs as antigen-presenting cells. In vitro allergen-induced proliferation and cytokine production were evaluated in the presence of B7-blocking reagents. RESULTS: Allergic individuals had a significantly higher proportion of AMs expressing the CD80 molecule than control subjects (28.5% +/- 14.8% vs 1.4% +/- 1.2%; P <.001), whereas no difference was observed in CD86 expression (2.0% +/- 2.3% vs 1.1% +/- 0.6; P >.1). In a large proportion of the asthmatic subjects we studied, AMs were presenting soluble antigens (tetanus toxoid and streptolysin-O) to freshly isolated T cells more efficiently than AMs from nonatopic control subjects. Finally, both T-cell proliferation and cytokine production of D pteronyssinus- specific established T-cell lines were inhibited by a CD80-blocking antibody in a dose-dependent manner. CONCLUSION: Costimulation by means of CD80 expressed by AMs is probably involved in the amplification of the allergen-specific T-lymphocyte response in the airways of asthmatic subjects.
BACKGROUND: Alveolar macrophages (AMs) are more efficient antigen-presenting cells in allergic individuals than in nonatopic subjects. OBJECTIVE: We studied whether this difference may be correlated to increased expression of membrane costimulatory molecules, such as the B7 molecules (CD80 and CD86). METHODS: Eleven subjects with allergic asthma sensitized to Dermatophagoides pteronyssinus and 5 healthy nonatopic volunteers underwent bronchoalveolar lavage, and the costimulatory molecule expression on AMs was evaluated. Peripheral blood T cells, either freshly isolated or as established D pteronyssinus -specific cell lines, were cultured with autologous monocytes or AMs as antigen-presenting cells. In vitro allergen-induced proliferation and cytokine production were evaluated in the presence of B7-blocking reagents. RESULTS: Allergic individuals had a significantly higher proportion of AMs expressing the CD80 molecule than control subjects (28.5% +/- 14.8% vs 1.4% +/- 1.2%; P <.001), whereas no difference was observed in CD86 expression (2.0% +/- 2.3% vs 1.1% +/- 0.6; P >.1). In a large proportion of the asthmatic subjects we studied, AMs were presenting soluble antigens (tetanus toxoid and streptolysin-O) to freshly isolated T cells more efficiently than AMs from nonatopic control subjects. Finally, both T-cell proliferation and cytokine production of D pteronyssinus- specific established T-cell lines were inhibited by a CD80-blocking antibody in a dose-dependent manner. CONCLUSION: Costimulation by means of CD80 expressed by AMs is probably involved in the amplification of the allergen-specific T-lymphocyte response in the airways of asthmatic subjects.
Authors: Krista M Heinonen; Nadia Dubé; Annie Bourdeau; Wayne S Lapp; Michel L Tremblay Journal: Proc Natl Acad Sci U S A Date: 2006-02-13 Impact factor: 11.205
Authors: G P Shi; R A Bryant; R Riese; S Verhelst; C Driessen; Z Li; D Bromme; H L Ploegh; H A Chapman Journal: J Exp Med Date: 2000-04-03 Impact factor: 14.307
Authors: Mónica Cicuéndez; Laura Casarrubios; Nathalie Barroca; Daniela Silva; María José Feito; Rosalía Diez-Orejas; Paula A A P Marques; María Teresa Portolés Journal: Int J Mol Sci Date: 2021-06-22 Impact factor: 5.923