Objective: To determine the effects of TGF-beta1 on the expression of the alpha1, alpha2, alpha5, alpha(v), and alpha6 integrin subunits and on vinculin, and F-actin in human peritoneal fibroblasts.
Design: Descriptive study using cell culture, reverse transcriptase-polymerase chain reaction (RT-PCR), and immunofluorescent and confocal microscopy.
Setting: Academic medical center.
Patient(s): Gynecological surgery patients.
Main outcome measure(s): Effects of TGF-beta1 on the steady state levels of alpha5, alpha(v), and alpha6 integrin transcripts were examined in the normal peritoneal fibroblasts using RT-PCR. Expression levels of the alpha1, alpha2, alpha5, alpha(v), and alpha6 integrin subunits and of F-actin were measured by immunofluorescent microscopy. The distribution pattern of the integrin subunits, vinculin, and F-actin were examined using confocal microscopy.
Result(s): TGF-beta1 significantly up-regulated the expression levels of the alpha5, alpha(v), and alpha6 integrin subunits and modulated their expression pattern, resulting in relatively higher levels of these subunits in the focal contacts of peritoneal fibroblasts. It allocated vinculin expression primarily to the focal contacts of cells and caused distortion of F-actin structure. The transcript levels of the alpha5, alpha(v), and alpha6 integrin subunits were not altered by TGF-beta1 treatment.
Conclusion(s): TGF-beta1 may promote postoperative adhesion formation by inducing the migration of peritoneal fibroblasts by altering the expression levels and patterns of specific integrin subunits, vinculin, and F-actin.