Topical Administration of G-CSF Ameliorates Refractory Cutaneous Ulcers: A Clinical Case Series

Objective: Granulocyte colony-stimulation factor (G-CSF) is a chemokine that stimulates granulocyte proliferation and maturation and mobilizes bone marrow-derived stem cells into the bloodstream. G-CSF treatment has been shown to enhance tissue repair in various conditions characterized by chronic wounds; however, the mechanisms by which this cytokine promotes chronic wound healing remain unclear. The effect of recombinant G-CSF on wound healing was examined in six patients with intractable chronic cutaneous ulcers. Methods G-CSF was topically applied at 6 µg/cm2 over the ulcers daily for 14 days. The wound conditions were assessed using DESIGN-R, a comprehensive scoring system established by the Japanese Society of Pressure Ulcers that monitors ulcers’ severity and healing states. Results The mean plasma concentration of G-CSF increased from 34.5 ± 14.1 µg/ml on day 0 to 70.8 ± 61.6 µg/ml on day 7; this increase was positively correlated with that of the WBC count. Total cutaneous ulcers graded with DESIGN-R scores significantly improved on day 7 (p < 0.05). Conclusions Topical administration of G-CSF induces amelioration of refractory cutaneous ulcers, probably via flare-up of inflammation without any damaging side effects.