Increased clinical and histological severity of arthritis in transgenic mice with impaired TGFβ-signalling in T cells. (a) The time course of the severity of arthritis after the booster injection (day 0) of one long-term experiment is shown. This experiment involved six wild-type and eight transgenic mice. Means ± SEM are shown. (b) The maximum clinical arthritis score of mice with a clinical score of at least grade 1 during the observation period of four separate short-term experiments was significantly higher in transgenic mice than in wild-type mice (mean ± SEM; **P = 0.001). (c) Mice with a clinical score of at least grade 1 were analyzed histologically for inflammatory and degenerative changes. Transgenic mice had significantly higher histological scores than wild-type mice (mean ± SEM; *P < 0.05). TG, tg, transgenic; WT, wt, wild-type.