Differential expression of alpha smooth muscle cell actin in human fibroblasts isolated from intraperitoneal adhesions and normal peritoneal tissues.

OBJECTIVE: To determine whether alpha smooth muscle cell actin (alphaSMCA) is expressed in human fibroblasts isolated from normal peritoneal and adhesion tissues.
DESIGN: Prospective, experimental study.
SETTING: University medical center. PATIENT(S): Five patients undergoing laparotomy for adhesiolysis for pelvic pain. INTERVENTION(S): Primary culture of fibroblasts from both peritoneum and adhesion tissues. MAIN OUTCOME MEASURE(S): Immunohistochemistry techniques were used to determine whether alphaSMCA was present in normal peritoneal and adhesion fibroblasts from the same patients. Cultured fibroblasts from all tissues were also fixed on slides and stained with alphaSMCA monoclonal antibody labeled with immunofluorescence. RESULT(S): Alpha SMCA protein was present in very low levels in the cytoplasm of normal peritoneal fibroblasts from all five subjects, as compared with high levels present in adhesion fibroblasts from the same patients. CONCLUSION(S): Adhesion fibroblasts develop a specific phenotype, an adhesion phenotype, which in part is characterized by the over-expression of alphaSMCA. The over-expression of alphaSMCA in adhesion fibroblasts indicates a possible response to peritoneal injury. Regulation of alphaSMCA might alter peritoneal healing and might provide the opportunity to reduce postoperative adhesion development.