BCR-ABL1 positive B-ALL can undergo T-cell lineage shift to become CD19 negative T-ALL

摘要

Lineage shifts in acute lymphoblastic leukemia (ALL) are uncommon and if they occur usually involve a switch from lymphoid to myeloid lineage. Here we report the observation of a B- to T-cell switch in a positive B-ALL that was engrafted in immune deficient NOD. /SzJ (NSG) mice. We studied the engraftment of 4 positive B-ALL cases (Table ), and observed the unexpected appearance of a positive T-ALL for 1 of the 4 cases (XC49). These data indicate that a switch from B-ALL to T-ALL is possible, and that this could be a novel mechanism to develop resistance against anti-CD19 directed therapy in some B-ALL cases.