The incidence of acute and chronic GVHD (aGVHD, cGVHD) was lower compared to DLIs or second HCTs as salvage strategies14,29, with only one patient ( ~ 7%) developing grade 3 aGVHD and one ( ~ 7%) developing moderate cGVHD post-TTCR-C4 infusion. This evidence concerns the gene C4A and chronic graft versus host disease.