Purpose. Elderly patients are susceptible to wound healing problems due to impaired neovascularisation in tissue repair. We investigated influence of surgical wound fluid (WF) obtained from both young and aged patients after musculoskeletal surgery on in-vitro recruitment and differentiation of endothelial progenitor cells (EPCs). Further, VEGF and TGF-b1 in WF were measured and blockade experiments were performed to analyze the role of both cytokines in EPC recruitment.
Methods: WF was obtained from young (28 ± 5 years, n = 14) and elderly (74 ± 8 years, n = 15) patients at 3, 8, and 24 hours after surgery. EPCs were isolated from healthy donors and incubated (72 hours) in medium substituted by WF. EPC number/differentiation was determined by fluorescence-microscopy and flow-cytometry after staining for DiLDL and lectin. CBF or ELISA was used to measure VEGF and TGF-b1 in WF. For blockade experiments, WF was mixed with antibodies against VEGF/TGF-b1 before incubation.
Results: A significantly higher number and increased differentiation of EPC can be observed after incubation with WF from young compared to elderly individuals. VEGF and TGF-b1 were higher in young patients' WF, and blockade of both cytokines reduced EPC numbers significantly.
Conclusion: Impaired wound healing in the elderly could be a result of dampened recruitment of EPC to site of affliction, possibly due to low VEGF/TGF-b1 levels. .