CD40LG and graft versus host disease: RIDD inhibition with intact XBP-1s expression in S729A B cells resulted in much higher IgM and MHCII expression compared to WT, XBP-1KO and S729A/XBP-1KO B cells (Figure 6 and Supplementary Figure 7), highlighting the role of RIDD in suppressing GVHD.