Deficiency of CX3CR1 delays burn wound healing and is associated with reduced myeloid cell recruitment and decreased sub-dermal angiogenesis

The development of a good blood supply is a key step in burn wound healing and appears to be regulated in part by myeloid cells. CX3CR1 positive cells have recently been identified as myeloid cells with a potential role in angiogenesis. The role of functional CX3CR1 system in burn wound healing is not previously investigated. A 2% contact burn was induced in CX3CR1(+/gfP) and CX3CR1(gfp/gfp) mice. These transgenic mice facilitate the tracking of CX3CR1 cells (CX3CR1(+/gfP)) and allow evaluation of the consequence of CX3CR1 functional knockout (CX3CR1(gfp/gfp)) on burn wound healing. The progression of wound healing was monitored before tissue was harvested and analyzed at day 6 and day 12 for migration of CX3CR1 cells into burn wound. Deficiency of a functional CX3CR1 system resulted in decreased recruitment of CX3CR1 positive cells into the burn wound associated with decreased myeloid cell recruitment (p < 0.001) and reduced maintenance of new vessels (p < 0.001). Burn wound healing was prolonged (p < 0.05). Our study is the first to establish a role for CX3CR1 in burn wound healing which is associated with sub-dermal angiogenesis. This chemokine receptor pathway may be attractive for therapeutic manipulation as it could increase sub dermal angiogenesis and thereby improve time to healing. (C) 2011 Elsevier Ltd and ISBI. All rights reserved.