Thymic cells (IMAGE) University of California - Riverside Caption Image shows thymic cells (mouse model). Nuclei of all cells present are dark blue, M cells are turquoise, and B cells (lymphocytes) are red or red/green. Credit Lo lab, UC Riverside. 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.