Levels of TNFα in long-term bone marrow culture supernatants.

Dots represent individual values of TNFα in LTBMC supernatants harvested on confluence and determined by means of ELISA in 26 patients with RA and 11 healthy controls. The mean concentration of the cytokine in patients and control subjects and the 95% confidence limits are indicated by horizontal lines and dotted rectangles, respectively. Comparison was performed using the nonparametric Mann-Whitney test (P =  .0005).