The effect of RWJ-67657 (0, 350, 700 or 1400 mg) on the percentage of monocytes producing IL-1β (a,d), TNFα (b,e) or IL-12 (c,f) after an in vitro LPS challenge of blood taken 6 (a-c) and 24 h (d-f) after an in vivo LPS injection. The line represents the regression line. Each square represents an individual. The P-value is given when the slope of the regression line significantly differs from 0.