TABLE 2.

Effects of OM and purified LPS on cytokine and chemokine secretion by human meningioma cells^a

Challenge	Doseb	Cytokine levels (ng/ml)b
		IL-6	IL-8	MCP-1	RANTES	GM-CSF
N. meningitidis MC58	2.5 × 104 -2.5 × 106	30c	18c	2.4-2.7c	0.8-1.5c	0.2-0.5c
OM (MC58)	1.0	1.0 ± 0.2d	6.3 ± 0.6	3.8 ± 0.6	0.3 ± 0.08	NDe
	0.1	1.4 ± 0.1	6.3 ± 0.6	4.6 ± 1.3	0.06 ± 0.03	ND
	0.01	0.7 ± 0.2	6.1 ± 1.7	2.9 ± 0.9	0.02 ± 0.02	ND
LPS (MC58)	1.0	1.5 ± 0.2	6.8 ± 0.6	2.2 ± 0.1	2.1 ± 0.5	0.09 ± 0.02
	0.1	1.3 ± 0.3	6.4 ± 1.5	2.3 ± 0.1	2.5 ± 0.6	0.04 ± 0.02
	0.01	1.3 ± 0.3	8.5 ± 2.6	2.3 ± 0.2	2.2 ± 0.4	0.07 ± 0.07
	0.001	0.5 ± 0.02	5.7 ± 0.3	2.2 ± 0.2	0.97 ± 0.2	0.02 ± 0.002
Control (medium only)		0.03	0.19	0.11	0.02	0.02

^aData for OM and purified LPS are compared to the levels of cytokine secretion induced by the intermediate concentrations of Pil⁺ bacteria used to challenge meningioma cells (see Fig. 3); at these concentrations the relative amounts of LPS in all the preparations were similar (18, 30).

^bDoses are given in micrograms per milliliter, except for the N. meningitidis MC58 dose, which is given in CFU per milliliter; cytokine levels measure protein accumulation at 24 h.

^cLevel of protein secreted by cells challenged with viable bacteria.

^dThe data are means ± standard deviations based on triplicate wells.

^eND, not detected.