Fig. 2

Apoptotic cell injection favors the induction of collagen-specific T regulatory cells (Treg). Cells from the lymph nodes of collagen-induced arthritis mice (CIA) receiving or not receiving apoptotic cell injection (+ApoCell) were harvested at sacrifice and cell proliferation was assessed through 5-Bromo-2’-deoxyuridine (BrDU) incorporation and counting in the presence of increasing concentrations of collagen antigen, Mycobacterium tuberculosis (MBT), or CD3-specific antibodies, as indicated (a-c). Data are shown as mean ± SEM from one representative experiment out of three with five mice per group; *p < 0.05, **p < 0.01, ***p < 0.001, vs. CIA group (nonparametric unpaired t test). In addition, cellularity was assessed, and CD4⁺ T cell and Foxp3⁺ Treg percentages and absolute numbers in the spleen (d, e) and lymph nodes (LN) (f, g) were determined. Data are shown as means from seven independent experiments; each experiment includes five mice per group; *p < 0.05, **p < 0.01 (parametric paired Student t test). Suppressive assays were performed using Treg isolated from the spleens of the previous treated and untreated CIA mice, and added at a different ratio into collagen-specific or MBT-specific co-cultures, or in CD3/CD28-stimulated T cell cultures, and responder T cell proliferation was assessed by BrdU incorporation and counting (h). Data are shown as mean ± SEM from one experiment with five mice per group; **p < 0.01, nonparametric unpaired t test