FHA-induced cytokine secretion in U-937 derived macrophages, fresh human monocytes, and BEAS-2B cells.

Cells were incubated for two hours with 5 µg/ml FHA, washed and further incubated for 16 hours with media alone. TNF-α, IL-8, and IL-10 levels were analyzed in cell supernatants by ELISA. These are representative values from one of three experiments performed under similar conditions. Statistical significance was analyzed by t test (two-sample test, assuming equal variances); FHA induced significant responses in all cases where cytokines could be detected (p < 0.000001).
ND = not detected.