Repeated Infusions of Mesenchymal Stromal Cells in Children With Osteogenesis Imperfecta

This is a pilot study to evaluate the safety and efficacy of repeated MSC infusions to subjects with OI. This study will evaluate subjects on two separate strata. Stratum A will include subjects with a diagnosis of Type II or Type III osteogenesis imperfecta who have previously undergone a bone marrow transplant. Stratum A may use previously harvested and cryopreserved bone marrow mononuclear cells from original BMT donor or freshly harvested or cryopreserved bone marrow mononuclear cells obtained from a haploidentical healthy parent or sibling. Stratum B will include subjects with Type II or III osteogenesis imperfecta who have not undergone a bone marrow transplant. Stratum B will only receive freshly harvested or cryopreserved bone marrow mononuclear cells from a haploidentical healthy parent or sibling. Participants will receive MSC infusions approximately every 4 months to complete a total of 6 infusions over 20 months. Participants will be followed for 12 months post their last MSC infusion.