Action of Antibodies on a B Cell (VIDEO) University of Würzburg This video is under embargo. Please login to access this video. Caption This happens in the first 30 minutes after a living Raji B cell comes into contact with the dye-labelled antibody OFA: The yellow signal comes from the protein actin; it shows how protrusions of the cell membrane develop. In magenta, the signal of the antibody. Credit Arindam Ghosh / University of Wuerzburg Usage Restrictions none 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.