EFFECT OF TRANSFORMING GROWTH-FACTOR-BETA ON POSTOPERATIVE ADHESION FORMATION AND INTACT PERITONEUM

Transforming growth factor β (TGFβ) is an extremely potent chemoattractant for macrophages, mononuclear leukocytes, and fibroblasts. It also acts as a potent stimulant for collagen and fibronectin synthesis and inhibits epithelial cell growth. TGFβ plays an important role in healing many types of wounds, but its role in peritoneal adhesion formation is not known. These studies were performed to determine if TGFβ could affect postoperative wound healing in a rat model. In the first experiment, 20 rats were divided into two groups and received either 2 μg TGFβ or control diluent IP daily for 5 days after surgical injury to the uterine horns. The severity of the adhesions were graded 2 weeks postoperatively using a score of 0-3. The TGFβ group showed a higher adhesion score at 2 weeks compared to control, 2.9 ± 0.34 and 1.6 ± 0.61, respectively (P < 0.001). On H&E stained sections of the adhesions, there was an increase in the number of both inflammatory cells and fibroblasts in the TGFβ-treated animals. A comparison trial of bone-derived TGFβ (a gift from Collagen Corporation, Palo Alto, CA) versus recombinant TGFβ (a gift from Oncogen, Seattle, WA) versus control using the same protocol as above showed that both sources of TGFβ were more effective in promoting postoperative adhesions when compared to controls, and there was no difference between TGFβ groups, 3.0 ± 0 for both TGFβ groups, and 2.2 ± 0.91 for control (P < 0.001). TGFβ did not induce adhesions when given in the same dosage for 5 days ip in unoperated rats, although it did induce fibrosis if injected into the abdominal wall. These data suggest that TGFβ may play a role in stimulating fibrosis in postoperative fibrinous adhesions, but has no effect on intact mesothelium. Prevention of TGFβ production postoperatively may help prevent adhesion formation. © 1992.