[Increased granulocyte/macrophage colony stimulating factor production by mononuclear cells from patients with...

The in vitro production of granulocyte/macrophage colony stimulating factor (GM-CSF) by mononuclear cells from the peripheral blood of patients with bronchial asthma (BA) was examined by enzyme-linked immunosorbent assay (ELISA). In 3 of 12 cases studied, mononuclear cells from BA patients produced GM-CSF without stimulation. And in 5 of 12 cases studied, mononuclear cells from BA patients produced GM-CSF in response to IL-2. Mononuclear cells from patients with other diseases (n = 13) and healthy volunteers (n = 6) did not release any detectable (> or = 7.5 pg/ml) GM-CSF. The culture media of mononuclear cells from BA patients showed activities for stimulating the proliferation and survival of eosinophils, and these activities were partially inhibited by anti-GM-CSF antibodies. GM-CSF production by mononuclear cells from BA patients treated with prednisolone was lower than that of mononuclear cells from untreated BA patients. And prednisolone showed a reduction in the GM-CSF production from mononuclear cells in response to IL-2. These results suggest that GM-CSF production by mononuclear cells may play a role in the pathogenesis of BA.