Induction of allergen-specific T-cell proliferation by human alveolar macrophages (AMΦ) after endobronchial allergen provocation in asthmatics. A, Proliferation of autologous CD4+ lymphocytes (T) after co-culture with AMΦ isolated from bronchoalveolar lavage from lung segments challenged with saline (S), one-tenth of the standard dose (A1/10) and the standard allergen dose (A), AMΦ/T-cell ratio 3:10. B, Chemokine levels in the supernatant of co-cultures. Bars indicate mean values (n = 7), data were analyzed by one way ANOVA. *P < .05, and **P < .01.