Abstract
Osteopetrosis was induced in lethally irradiated, normal mice of grey-lethal and microphthalmic stocks by cell infusions prepared from the spleens of osteopetrotic littermates. Failure of skeletal remodeling became evident within a few weeks after transplantation as calcified cartilage and bone accumulated excessively in the active metaphyses of the long bones. The massive lesions produced were extensively infiltrated with abnormal osteoclasts.