Figure 6

Tumour necrosis factor-α (TNF-α)-mediated interleukin (IL)-1β and IL-6 production by normal monocytes pretreated with IL-10 and/or macrophage colony-stimulating factor (M-CSF). Purified normal monocytes from different individuals were preincubated for 3 days with or without 50 ng/ml M-CSF, 25 ng/ml IL-10, or IL-10 plus M-CSF and then stimulated for 24 hours with or without 10 ng/ml TNF-α, 30 μM dibutyryl cAMP (dbcAMP), or TNF-α plus dbcAMP. Concentrations of IL-1β and IL-6 in culture supernatants were measured in triplicate by the quantitative sandwich enzyme-linked immunosorbent assay. Values are the mean ± standard error of the mean. n, number of samples tested.