Reduced proportion of CD45RO+γδ T cells in Crohn's disease (CD) and ulcerative colitis (UC). Proportions of circulating γδ T cells in healthy controls (69·8 ± 4·4%, n = 22), active CD patients (31·4 ± 6·2%, n = 15) and active UC patients (32·1 ± 4·5%, n = 15) expressing CD45RO; t-test was applied. A P-value < 0·05 was considered statistically significant (***P < 0·001). Error bars represent standard error of the mean, horizontal lines represent mean.