Figure 4.

Effect of recombinant IL-4 on CXC chemokine secretion by human alveolar epithelial A549 cells infected with M. bovis BCG. Cells were treated with medium (no stimuli) or increasing doses of IL-4 for 2 h prior to infection with M. bovis BCG ( MOI = 5). After 24 h incubation, supernatants was collected and (a) CXCL-8 or (b) CXCL-10 were measured by ELISA. Data shown are the mean ± SD of four independent experiments. The percentage in parentheses indicates inhibition in the presence of IL-4 compared with M. bovis BCG cultures which did not receive IL-4.