Platelet-derived growth factor isoforms prevent cell death during starvation of AKR-2B fibroblasts .

Simm A ; Hoppe V ; Gazit A ; Hoppe J

Department of Physiological Chemistry , Theodor-Boveri-Institute , University of Wurzburg , Germany .

J Cell Physiol 160 : 295-302 ( 1994)

Abstract
Confluent AKR-2B fibroblasts rapidly desintegrate upon removal of serum until a final density of approximately 50% of the initial value was reached after 12 h . This density remained unchanged for at least 48 h . Platelet-derived growth factor ( PDGF)-BB stimulated more than 95% of these cells to divide . PDGF-AB or -BB added immediately after serum removal caused complete survival of the cells , but did not stimulate cell division as demonstrated by two-dimensional DNA flow cytometry . PDGF-AA was less effective leading to approximately 75% of the initial cell density . This effect could be augmented by the addition of ocadaic acid , a potent phosphatase inhibitor , suggesting that protein phosphorylation plays a role in this process . By using tyrphostin AG807 it was demonstrated that the signaling mechanism for survival requires receptor tyrosine autophosphorylation .