Upon the surgical implantation of a biomaterial, a host of inflammatory cells, including macrophages, will initially interact with its surface. It is now recognized that the function and/or phenotype of a macrophage can be dictated not only by the cytokine and cellular environment of the wound site, but also by the material itself. Depending on which phenotypic spectrum is stimulated, the macrophage can promote healing by initiating appropriate tissue repair or defend the body by either degrading the material or creating a fibrous capsule around it. Studies on biomaterial biocompatibility often focus on the response of tissue specific cells (such as osteoblasts or fibroblasts); however because macrophages are one of the first cell types to interact with the biomaterial, they have the capacity to direct downstream cellular events. Therefore, understanding the influence of a biomaterial on macrophage signaling is essential to elucidate not only the immediate host response but ultimately also the long-term performance. It is becoming well established that cellular activity and function are influenced by the surface characteristics of the biomaterial. Since cell signaling occurs at the nanoscale level, surface modifications at the scale of the cell’s sensing apparatus have a great potential to influence signaling events. This project investigates the response of macrophages to machine polished titanium compared to surface modified titanium (generated by oxidative nanopatterning). Techniques used in this study include in vitro cell culture, immunofluorescence labeling and electron microscopy. Understanding how the physiochemical surface of a material alters macrophage behavior will aid in the intelligent design of biomaterials, which can be tailored for specific applications.

​Project in collaboration with Dr. A. Nanci (UdeM)