Table 1. FHA-induced cytokine secretion in U-937 derived macrophages, fresh human monocytes, and BEAS-2B cells.

		TNF-α (ng/ml)	IL-8 (ng/ml)	IL-10 (ng/ml)
U-937 cells	media only	0.025±0.015	2.7±0.3	0.013±0.001
	+ FHA	0.360±0.02	32±3.2	2.2±0.071
Fresh monocytes	media only	ND	ND	ND
	+ FHA	4.24±0.04	76±2.3	0.47±0.1
BEAS-2B cells	media only	ND	0.108±0.008	ND
	+ FHA	ND	1.341±0.069	ND

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.