Assessing Macrophage Phenotype During Tissue Repair

Macrophages are thought to play important roles in tissue repair, from host defense to angiogenesis and new tissue formation. The role of macrophages in repair of different tissues is an active area of inquiry, particularly in settings of impaired healing. In this chapter, we describe methods for isolating monocyte/macrophage cell populations from damaged tissue and characterizing the phenotype of these cells. Cells are isolated from tissue by enzymatic digestion, and then monocyte/macrophage populations can be sorted by magnetic separation. The phenotype of these cells is assessed by real-time PCR, flow cytometry and ELISA. A complementary approach of assessing monocyte/macrophage phenotype by immunofluorescence staining of cryosections is also described. This combination of approaches to study the macrophage phenotypes expressed during tissue repair will lead to better understanding of the roles of macrophages in tissue repair and new therapeutic avenues for improving healing.