Tissue sample from the spleen of a mouse: (IMAGE) University of Bonn Caption The B cells (green) interact with factor VIII (red). Credit Photo: AG Becker-Gotot / UKB 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.