Patent ID: 8431767

Claim:
A transgenic immunodeficient non-obese diabetic (NOD) mouse homozygous for the scid mutation and having an IL2 receptor gamma chain deficiency, whose genome comprises a nucleic acid encoding xenogeneic Stem Cell Factor operably linked to a promoter, wherein the animal expresses the xenogeneic Stem Cell Factor, with the proviso that no exogenous GM-CSF is expressed in the transgenic immunodeficient mouse, wherein administration of human stem cells to the mouse in the absence of conditioning by irradiation prior to administration of the human stem cells results in similar or greater levels of engraftment of the human stem cells compared to a non-obese diabetic (NOD) mouse homozygous for the scid mutation and having an IL2 receptor gamma chain deficiency which is conditioned by irradiation prior to administration of human stem cells and which does not express the xenogeneic Stem Cell Factor.