Monocyte chemoattractant protein-1 (MCP-1) and macrophage infiltration into the skin after burn injury in aged mice

Clinical observations and laboratory studies have shown a delay in dermal wound healing in aged subjects. Since macrophages play a key role in wound healing, we investigated age related differences in MCP-1 production and monocyte recruitment to the wound following burn injury using a murine model. The present study shows that there is an increase in MCP-1 levels in the burned-normal skin interface at 1-day post burn in both young and aged burned mice compared to sham injured mice. However, the levels of MCP-1 in aged burned mice (133.16 +/- 36.55 pg/m protein) were approximately half the levels of young burned mice (286.15 +/- 45.36 pg/mg protein, P < 0.05). Additionally, at 4 days post burn. MCP-1 levels in aged mice (290.73 +/- 101.98) reached the same levels as in young mice (243.97 +/- 36.71). There was no difference in macrophage accumulation into the wound between young and aged at either time point. These data demonstrate that the difference in dermal MCP-1 levels between the young and aged is not associated with a difference in macrophage infiltration to the wound following burn injury, suggesting that the lower MCP-1 content in the aged is possibly affecting other phases of wound healing in the aged. (C) 2003 Elsevier Science Ltd and ISBI. All rights reserved.