Congenital Osteopetrosis in Mice Cured by Parabiotic Union with Normal Siblings

Osteopetrotic mice of grey-lethal and microphthalmic stock parabiotically joined to normal siblings rapidly recover from their inherited bone disorder. When parabiosis is performed at ten days of age, removal of all excess skeletal matrix and expansion of the hematopoietic centers to the normal extent was achieved by six weeks of age. Even by three weeks postoperatively, the parabiotic mutants more closely resembled normal controls than unoperated mutants. In the histology of the long bones, there was no indication that the normal mice had been adversely affected by parabiotic union to the mutants. The corrective influence of parabiosis is believed to be humoral in nature and derived from the normal parabiont. (Endocrinology91: 916, 1972)