To assess the ability of DP8α Tregs to kill myeloid cells, two cell lines, namely K562, of the erythroleukemia type, and U937, of the myeloid lineage, as well as two types of primary ex vivo sorted cells, CD19+ B cells and CD14+ monocytes, were co-cultured with Treg clones. The gene discussed is CD19; the disease is erythroleukemia.