CASP3 and rheumatoid arthritis: Preliminary results obtained through Western blot analyses revealed that DPSCs up-regulated PD-L1 also when co-cultured with RA aPBMCs (***P < 0.001 vs. DPSCs alone; §§§P < 0.001 vs. DPSCs after RA rPBMCs co-culture; Fig. 7B) and, at the same time, induced activation of caspase 3 in RA aPBMCs when compared to RA aPBMCs cultured alone (*P < 0.05 vs. RA aPBMCs alone; Fig. 7C).