Robert L. Satcher, MD, Ph.D.

Orthopaedic Oncology
Department of Orthopaedic Surgery                                                                                                      
Northwestern University
r-satcher@northwestern.edu
312-908-7937

Current Research

Bone tissue culture applications in medicine

Bone substitutes synthesized using cell culture is a promising alternative for providing material for patients who sustain bone loss from trauma, infection, surgery, etc.  The mechanical environment plays a central role in bone growth and remodeling.  Mechanical forces impact the differentiation of osteoprogenitor to osteoblasts, and probably stimulate mature osteoblasts to produce the osteiod, which becomes bone.  Osteoblasts are subjected to fluid shear stress and substrate strain in vivo.  My aim is to determine how mechanical forces can be used and controlled in vitro to stimulate bone cell growth and matrix production.  We will simulate forces occurring in the micromechanical environment of the musculoskeletal system by subjecting cultured osteoblasts and marrow stem cells to combined forces from fluid shear stress and substrate loading. 

Mechanism of metastasis

The skeleton is a frequent target of metastasis.  Cancerous cells interact with the vascular endothelium and musculoskeletal system in the process of metastatic spread to bone.  My aim is to develop an in vitro model for metastasis.  We will focus on the initial steps required for successful metastasis:  (1) adhesion to and diapadesis across the vascular endothelial monolayer; and (2) adherence and growth to bone matrix.  In addition, we will investigate the role of physical forces in each of these interactions.  

Pathogenesis of atherosclerosis

Shear stress affects vascular endothelial cell structure.  Cells become elongated and aligned along the primary vector of shear stress when there is laminar flow.  Atherosclerotic plaques form more frequently in areas of disturbed flow (with flow separation and recirculation regions) such as occurs at curves and bifurcations in the artery.  My aim is to investigate the mechanism by which shear stress imparted to the cell membrane induces the observed changes in cell architecture and function.  In order to accomplish this we will (1) characterize the mechanical environment on the scale of individual cells using computational modeling; (2) develop in vitro systems to expose groups of cells to prescribed mechanical stimuli; (3) determine the ultrastructural and cytoskeletal modifications provoked by shear stress; and (4) characterize and model the mechanical properties of individual and small groups of cells.

Recent Publications