Other rare complications have been reported including the development of inflammatory or infectious lesions. A fatal crisis occurred in a sibling donor for allogeneic transplantation who had hemoglobin SC disease. These rare complications should be put in the context that G-CSF administration followed by apheresis to recover primitive hematopoietic cells from normal individuals has been utilized in all major transplant centers for more than a decade and has generally been safe and without significant complications. We propose to minimize the risk of serious complications by limiting the age range of research participants to 18-40 years and excluding those with a history of inflammatory disease, cardiovascular disease, thrombosis or pulmonary embolization, inflammatory skin disorders, hematological disease or hemoglobinopathy.