Figure 6.

Antigen-pulsed lung tissue MØs suppress asthmatic lung inflammation. (A) Groups of WT mice were instilled i.t. with OVA-pulsed MØs (OVA-MØ) or 5 × 10⁵ MØs alone. 9 d later, the mice were sensitized with OVA/alum and subsequently challenged with i.n. OVA on day 18 for three consecutive days to induce lung inflammation. Samples were collected 24 h after the last OVA challenge. (B) Representative H&E (top) and periodic acid-Schiff (PAS; bottom) staining of lung sections. Airway hyperresponsiveness to methacholine was assessed by invasive measurement of airway resistance. Bar, 100 µm. (C) Total BAL cells and numbers of eosinophils (Eos), neutrophils (Neu), lymphocytes (Lymph), and MØs from cytospin analysis. Cytokines in BAL were measured by ELISA (bottom). (D, top left) Expression of Foxp3 in CD4⁺ T cells from lungs analyzed by flow cytometry. (top right) Expression of Foxp3 versus CD62L in gated CD4⁺ T cells. (bottom) Absolute number of total Foxp3⁺ T_reg cells and CD62L^lo Foxp3⁺ T_reg cells in lungs. All results are the mean ± SD from four to five individual mice per group and representative of two independent experiments. *, P < 0.001.