Morphological transformation and chemotactic migration of fibroblasts by TGF-beta-related 25Kd polypeptide

25Kd is a polypeptide molecule that shows many characteristics of the transforming factor type beta. We have studied the ability of 25Kd to induce morphological changes and also chemotactic migration of normal and transformed fibroblasts. It was found that normal cells exposed to 25Kd show an aberrant morphology while transformed cells are no longer randomly distributed over the culture dish but instead organize into clusters. In vitro, 25Kd is a potent chemoattractant for fibroblasts at doses ranging from 0.1-5ng/ml. Complete inhibition of chemotaxis was achieved in the presence of anti-25Kd antibodies.