Method for allogeneic BMT of humanized CA mice in the absence of cytoreductive conditioning. Donor total BMCs from GFP transgenic mice were treated with Diprotin A and injected intravenously into 3-day-old humanized CA recipients that received a single injection of anti-CD122 antibody on day 2 after birth. Transplanted CA mice were analyzed across time for rescue from lethal anemia, hematology, growth velocity, fertility, hematopoietic chimerism, and GVHD.