Characterization of autologous lymphocyte proliferation by in vitro IL-4 polarized human monocyte-derived macrophages (MDM). A, Induction of proliferation by IL-4 polarized macrophages ± grass allergen extract. Three macrophage/lymphocytes ratios are shown (mean ± SEM, n = 8). B, Levels of cytokines/chemokines in supernatants of co-cultures (n = 6). Bars indicate mean values. Data were analyzed with one way ANOVA. *P < .05, ** P < .01, and *** P < .001.