Impaired allogeneic T cell stimulatory capacity of monocyte-derived dendritic cells (MD-DCs) from spondyloarthritis (SpA) patients. MD-DCs from SpA patients and healthy controls that were left unstimulated at baseline (H0), or were stimulated with lipopolysaccharide (LPS) for 6 h or 24 h (H6 and H24, respectively) were tested for their capacity to stimulate in vitro allogeneic CD4+ T cells. Results are expressed as 3H-deoxythymidine incorporation after 6 days of mixed lymphocyte reaction, in counts per minute (CPM) ratio. Bars represent the mean proliferation index and standard error of the mean induced by MD-DCs from 19 SpA patients and 24 healthy controls. The Wilcoxon test showed significant differences at H0 (*P <0.05) and H6 (**P <0.01). MLR, mixed lymphocyte reaction.