The Growth of Human Bone Marrow in Diffusion Chambers

S ummary . Diffusion chambers containing normal human bone marrow were implanted intraperitoneally into normal and irradiated mice and cultured for various periods. Granulocytes, macrophages and lymphocytes comprised the majority of the cells harvested in all cultures. The most impressive cell growth occurred when the chambers were implanted into primary hosts irradiated with 840 R and then retransplanted on Day 8 of the culture into secondary hosts irradiated with the same dose. Linear relationships were found between the number of nucleated cells inoculated into the chambers and the number of cells harvested after 8 or 10 days of culture in heavily irradiated hosts.