EFFECT OF INTERCEED ON EXTRACELLULAR MATRIX AND TGF-b1 EXPRESSION IN HUMAN PERITONEAL FIBROBLASTS AND MESOTHELIAL CELLS

L. April Gago MD, Ghassan Saed PhD, Rona X. Wang MD, Maher Jaber MD, Michael P. Diamond MD

   Objective: To evaluate the potential biologic effects of Interceed (oxidized regenerated cellulose) on the expression of transforming growth factor- b1 (TGF-b1) and extracellular matrix (ECM) molecules.

   Materials and Methods:  Interceed (oxidized regenerated cellulose) was dissolved and added to confluent, monolayer cultures of human normal fibroblasts (NF), adhesion fibroblasts (AF), and mesothelial cells (MC).  Control cells were maintained in media alone at the same pH.  After 24 hours of treatment, total RNA was then extracted from all cells.  Real time PCR was performed to determine the relative change in mRNA levels of Collagen I (Col I), Collagen III (Col III), Fibronectin, TGFb-1, and beta actin (a housekeeping gene) in response to treatment (n=4).  Student t-tests were performed for each cell type, comparing Interceed treated to control cells.  Calculated power for the statistically significant findings ranged from 65%-100%. 

   Results:  Interceed significantly increased the expression of TGF-b1 and Col I in human mesothelial cells by 13 and 23 percent, respectively.  Interceed treatment resulted in a 27% increase in the expression of Col I mRNA in the normal human fibroblasts.  Interceed also increased the expression of Col I in the adhesion fibroblasts by 9%, but this did not reach statistical significance.  As previously observed, untreated adhesion fibroblasts expressed more Col I than normal fibroblasts.  Interestingly, TGF-b1, which has been shown to increase the expression of ECM molecules, was differentially expressed at a significantly higher level in the Interceed treated mesothelial cells, but tended to be decreased in normal and adhesion fibroblasts.  Expression of Col III and fibronectin were not significantly increased in mesothelial cells nor normal or adhesion fibroblasts treated with Interceed.

 Conclusion:  Interceed, which has been shown in multiple human in vivo studies to reduce postoperative adhesion development, nonetheless, influences expression of factors commonly accepted to be associated with adhesiogenesis, increasing expression of TGF-b1 in mesothelial cells and collagen I in mesothelial cells and normal peritoneal fibroblasts, while tending to decrease TGF-b1 expression in adhesion fibroblasts. 

   Key Words:  Interceed, TGF-b1, Extracellular Matrix, Fibroblasts, Mesothelial Cells