Differential expression of TGF-beta 1 and TGF-beta 3 in serosal tissues ofhuman intraperitoneal organs and peritoneal adhesions

Elevated local expression of transforming growth factor (TGF-beta) has been associated with increased incidence of peritoneal adhesion formation. In t his study we determine whether differences in basal expression of TGF-beta in serosal tissue of peritoneal organs correlate with incidence of adhesion formation. Serosal tissue of parietal peritoneum, uterus, oviduct, ovary, omentum, large and small bowels as well as adhesions, skin, fascia, subcuta neous tissue, peritoneal fluid and serum were collected from 57 subjects wi th/without adhesions who were undergoing abdominal/pelvic surgery, To deter mine TGF-beta1 and TGF-beta3 mRNA and protein expression, total RNA and pro tein were isolated from these tissues and along with the fluids, subjected to quantitative RT-PCR and enzyme-linked immunosorbent assay (ELISA) respec tively, Tissue sections were immunostained for TGF-beta1 and TGF-beta3 prot ein. We found that TGF-beta1 and TGF-beta3 mRNA and protein are expressed i n these tissues and present in peritoneal fluids and serum, with considerab le variations in level of their expression. Comparatively, there was more v ariation in TGF-beta1 than TGF-beta3 expression without age or gender relat ion. Adhesions express a significantly higher TGF-beta1 mRNA and have the h ighest TGF-beta1:TGF-beta3 ratio, with lowest concentrations and ratio dete cted in omentum, small and large bowels; in contrast uterus expresses highe r TGF-beta3, with lowest concentrations detected in subcutaneous tissue and large bowels (P < 0.05), A similar trend was also observed for total (acti ve + latent) TGF-beta1 protein expression, with low active TGF-beta1 that w as not significantly different among the tissue extracts and fluids. Howeve r, the lowest active:total TGF-beta1 ratio was found in adhesions and ovary . In subjects with adhesions, the adhesions express significantly more TGF- beta1 compared to parietal peritoneum (P < 0.05), Immunoreactive TGF-beta1 and TGF-beta3 protein were present in various cell types in these tissues w ith intensity reflecting their mRNA and protein expression, In conclusion, we provided evidence that serosal tissue of various peritoneal organs and a dhesions express TGF-beta1 and TGF-beta3, Since TGF-beta is expressed diffe rently in these tissues and tissue injury often alters the expression of TG F-beta, we propose that tissues with a higher basal expression of TGF-beta may become predisposed to develop more adhesions compared to others.