Transforming Growth Factors Type β Inhibit Multibrug Transport in rat Astrocyte Cell Lines

Abstract

Astrocytes - like some endothelial cells of the blood-brain barrier - can express a multidrug transport system, which limits the intracellular accumulation of cytostatic agents and a variety of other substances. I observed that astrocytic multidrug transport can be modulated by cytokines: The transforming growth factors type β₁, β₂, and β_{1. 2} are specific inhibitors of multidrug transport in fetal rat brain astrocyte cell lines. Other cytokines or interleukins did not inhibit astrocytic multidrug transport. Interestingly, the inhibitory effect of TGF-4bT couId be antagonized by the bone morphogenetic protein BMP 2, a cytokine that is distantly related to TGF-β

Key Words:

• Multidrug resistance
• astrocytes
• transforming growth factor type β