TNF-α production by the colonic mucosa. Levels of TNF-α are measured in supernatants of organ cultures and presented as pg/μg of tissue protein, in the groups: untreated colitis, therapeutic- and prophylactic-thalidomide, placebo-treated, and normal controls, respectively (n = 10 in each group). Horizontal bars represent medians, boxes represent the 25th and 75th percentiles, and vertical bars represent ranges. Differences were analysed using one-way ANOVA with the Dunnett’s test for multiple comparisons. Significant differences are presented.