The Effect of Granulocyte-Macrophage Colony-Stimulating Factor on Human Dermal Fibroblast Proliferation

ABSTRACT

Granulocyte-Macrophage colony-stimulating factor(GM- CSF) is naturally generated protein that stimulates the survival, proliferation, and differentiation of myeloid progenitor cells. The determination of the molecular sequence of this protein by recombinant DNA technology enabled us to produce sufficient quantity for preclinical and clinical use. In the animal studies, rhGM-CSF to wounds has been reported to result in increased formation of granulation tissue, increased breaking strength, and reversal of wound contraction. A number of case reports have been published on the favorable effect of rhGM-CSF as a treatment for infected, nonhealing wounds, and ulcers. However, there are no clinical reports about the effect of GM-CSF on wound healing in normal patients. Therefore, in this report, we examined the effect of GM-CSF on the proliferation of human dermal fibroblasts which play a crucial role in wound healing process in vitro. To determine an optimal GM-CSF concentration for human dermal fibroblast proliferation, the cells were incubated with either one of 13 concentrations of GM-CSF(0 - 30mug/ml). The media used in this study was DMEM/F- 12(GIBCO, Grand Island, NY, USA). The fibroblasts were seeded at 1.5 x 104 cells/well in 500mul of medium including 10% fetal bovine serum and either one of 13 concentrations of GM-CSF in 24-well plates. The cells were incubated for 6 days at 5% CO2, 100% humidity at 37degrees C. On the 6th day of plating, fibroblast proliferation was determined by hematocytometer. Each concentration was tested 8 times.Low concentration of GM-CSF(below 5.0mug/ml) stimulated the proliferation of human dermal fibroblasts. How ever, high concentration of GM-CSF(over 10mug/ml) downregulated the proliferation of human dermal fibroblasts. The best fibroblast proliferation was seen at 1.0mug/ml of GM- CSF. These results demonstrated that GM-CSF influenced human dermal fibroblast proliferation and the GM-CSF concentration was critically important factor in vitro.