The frequencies of the generated/activated β7-expressing cells correlated ex vivo with the provision of leukemia-specific/antileukemic cells after (T-cell-enriched) MLC with Kit-pretreated (vs. untreated) WB, and in vivo with achieved (vs. not achieved) remission after induction chemotherapy, and with patients’ allocations to favorable (vs. unfavorable) risk types. The gene discussed is KIT; the disease is leukemia.