Leukemia inhibitory factor-transfected embryonic fibroblasts and vascular endothelial growth factor successfully improve the skin substitute wound healing by increasing angiogenesis and matrix production.

BACKGROUND AND OBJECTIVE

The combined application of cytokines on embryonic fibroblasts and dermal substitute were studied for optimal skin defect coverage. The mechanism of combined treatment of leukemia inhibitory factor (LIF)-transfected embryonic fibroblasts and vascular endothelial growth factor (VEGF) were elucidated and subsequently the in vivo applications of both were tested in an artificial dermal substitute.

METHODS

Mouse embryonic fibroblast cells, BALB-3T3, were stably transfected with mouse full-length LIF cDNA and added to various doses of VEGF for detection of signaling interaction. LIF-transfected cells and VEGF treatment were tested with pig-tendon derived collagen dermal substitute in the backs of BALB/c male mice up to for 14 days.

RESULTS

LIF-transfected cells as well as vector-transfected fibroblasts significantly proliferated by 1, 10, or 100 ng VEGF on days 3 and 5. Erk mitogen-activated protein (MAP) kinase phosphorylation was observed from 1 to 30 min in LIF-transfected and 10 ng of VEFG, and 1 to 60 min in LIF-transfected and 100 ng VEFG treatments. The cellular fibronectin levels also increased in LIF-transfected cells with 10 and 100 ng VEGF additions. In in vivo analyses, LIF-transfected embryonic fibroblasts with 50 microg of VEGF markedly enhanced collagen I expression and CD34 angiogenic marker on days 7 and 14.

CONCLUSION

LIF transfection and VEGF treatment enhanced phosphorylated-Erk-MAP kinase in vitro. In vivo study revealed that the combined application of LIF transfection of embryonic fibroblasts with an angiogenic factor such as VEGF in the template of a dermal substitute induced greater skin collagen production and angiogenesis in the dermal substitute.