The adenosine antagonist (colored) (IMAGE) University of Bonn Caption binds to tiny antennae on the surface of the immune cells, the adenosine receptors of type 2A. This slows down the immune troops. Credit Graphic: Pharmaceutical & Medicinal Chemistry/University of Bonn Usage Restrictions This image may be used together with the press release. License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.