ENHANCEMENT OF HUMAN NEUTROPHIL SURVIVAL AND ACTIVATION BY TGF-BETA-1

Transforming growth factor beta (TGF-beta) is a multifunctional growth factor which promotes the inflammatory process. We have investigated the effect of TGF-beta 1 on neutrophil survival, recruitment and activ ation. These last steps are essential for their participation in the i nflammatory response. Our results demonstrate that TGF-beta 1 at a con centration of 20-40 ng/ml is a potent neutrophil chemotactic factor. T he chemotactic activity induced by TGF-beta 1 is greater than that ind uced by fMLP (10(-8) M). Furthermore, TGF-beta 1 (20-30 ng/ml) induces neutrophil activation demonstrated by an increase of respiratory burs t and phagocytosis. Finally, TGF-beta 1 also enhances human neutrophil survival (43 to 93%) at concentrations as low as 2 to 20 ng/ml. This study provides evidence that TGF-beta 1 is capable of recruiting and a ctivating neutrophils at inflammatory sites and enhances their surviva l.