Cytokine and protease levels in healing and non-healing chronic venous leg ulcers

Leg ulcers present a common and recurring problem in older people creating discomfort and distress for the patient and a great cost to the health care services. Cultured keratinocyte grafts have been used by many investigators to stimulate healing of chronic venous ulcers. It has been proposed that they may do this by producing cytokines which modulate the healing process. However, the types and levels of cytokines in the leg ulcer fluid before and during healing arc not known. Wound fluid was collected from venous leg ulcers in 18 patients beneath occlusive Tega‐derm™ dressing for 4 to 6 h. The leg ulcers were divided on clinical criteria into ‘healing’ and ‘non‐healing’. PDGF‐AB, GM‐CSE IL‐1α, IL‐1β. IL‐6 and bFGF were measured by ELISA and the levels of IL‐1α, IL‐1β. and IL‐6 were also measured using biological assays. The effect of leg ulcer wound fluid on fibroblast and keratinocyte proliferation was measured indirectly by 3H‐thymidine incorporation and MTT assay. Total protein, albumin levels, fibronectin degrading activity and collagenase activity, both active and latent were measured. No statistically significant differences in the levels of cytokines or collagenase were identified between healing and non‐healing leg ulcers in the sample of leg ulcers studied. However, this study does give valuable information concerning the levels of cytokines and collagenase in chronic leg ulcer wound fluid.