The wound repair is control by monocyte linage cells

One of the most important clinical problems in caring for elderly patients is treatment of pressure ulcers. One component of normal wound healing is the generation of an inflammatory reaction, which is characterized by the sequential infiltration of neutrophils, macrophages and lymphocytes. In aged C57BL/6 mice, wound healing is relatively inefficient. We examined the effects of monocytes lineage cells for wound healing. First, we i.v.transplanted bone marrow cells from GFP mice (C57BL/6 background) to C57BL/6 mice. We found that the rate of wound repair was enhanced by the bone marrow transplantation. By Immunohistochemistry, we can detect GFP positive cells in wound site. By FACS analysis Gr-1+ (neutrophils) and CD11b+ cells (macrophages) are observed in wound tissues. These results indicate that macrophages and/or neutrophils have the capacity to repair wounded tissues. We compare the capacity to repair wound by aging. Although old bone marrow cells also enhanced wound repair by bone marrow transplantation, the rate of wound repair old bone marrow was lower than the transplantation of young bone marrow. These results indicate that wound healing is controlled by monocytes lineage cells including neutrophils and macrophages. These monocytes lineage cells of aged mice have lower capacity to repair wound than those of young mice.