Plasminogen activator/plasminogen activator inhibitor-1 and cytokine modulation by the PROACT™ System

Objective: To examine the effects of the PROACT treatment on the fibrinolytic system and inflammatory cytokines in human peritoneum. Design: Controlled clinical study. Setting: University hospital. Patient(s): Nine subjects undergoing laparotomy had peritoneal samples taken at the incision. Intervention(s): The PROACT applicator was inserted through the peritoneal incision, and treatment of peritoneum was performed twice. A peritoneal sample was taken from one treated area. At closure, the second treated sample and an additional control sample were taken. All four samples were snap frozen in liquid nitrogen. Samples were homogenized and protein content extracted. Main Outcome Measure(s): Concentrations of total and active transforming growth factor-beta 1 (TGF-β1), tumor necrosis factor-alpha (TNF-α), tissue-type plasminogen activator (t-PA), urokinase plasminogen activator (uPA), and plasminogen activator inhibitor 1 (PAI-1) were obtained. Result(s): Total TGF-β1 at opening was 30% less in treated samples. At closure, active TGF-β1 increased significantly (163%) in control samples and not in treated samples. Tumor necrosis factor alpha was detectable only in control samples at closure. During surgery, tPA levels showed a marked decrease in control samples vs. a small increase in treated samples. Levels of uPA increased significantly only in the control samples. In control samples, tPA/PAI-1 ratio was two thirds of treated sample ratio. Conclusion(s): Heating of the peritoneum with the PROACT™ System modulates the biologic tissue response to induce effects that would be consistent with inhibition of postoperative adhesion development.