Weights of mice engrafted with human HSC as newborns. Weights of nonirradiated NSG-Tg(hu-mSCF) and 100-cGy irradiated NSG and NSG-Tg(hu-mSCF) mice engrafted with human HSCs as newborns were obtained over time after weaning. (A) Male mice. (B) Female mice. Each symbol represents an individual data point. The lines represent the average of the individual data points.