Identification of Bone Marrow-Derived Cell Lineages Engaged in Endochondral Bone Repair Post Fracture

Mentor

Philipp Mayer-Kuckuk, PhD

Scope

Dedicated to innovative bone research, the bone cell biology and imaging group at Hospital for Special Surgery develops and applies molecular imaging technology in combination with traditional analysis methods to study osteogenesis in living subjects.

We have recently characterized a rib fracture model in C57/BL6 mice. Post fracture, healing is controlled by an endochondral bone repair process. In this study, we will employ the rib fracture healing model to assess the participation of bone marrow-derived cells to the healing stages. We plan to study animals harboring either CD34+ CD45+ GFP+ or CD34- CD45- GFP+ bone marrow. To generate these mice, we will isolate the bone marrow via multi-color fluorescence-activated cell sorting and transplant the isolated bone marrow into conditioned mice 8 weeks prior to fracture.

Data from pilot studies suggest an efficient rib bone marrow reconstitution at both lethal and sub-lethal conditioning regimes. We anticipate observing cells derived from the hematopoietic CD34+ CD45+ GFP+ compartment at the early, inflammatory healing phase while non-hematopoietic cells may have functions in the subsequent healing phases. Together, these data will help to dissect the source of repair cells and to discriminate between cells derived from bone marrow and other sources such as the periosteum.

Our long-range goal is to use the described strategy to isolate more defined subpopulations of bone marrow-derived cells in an effort to further define the origin of bone repair cells.

Contact

Marie Reumann
reumannm@hss.edu