Mouse melanoma (IMAGE) Salk Institute Caption A mouse melanoma tumor showing blood vessels (red), MHC proteins (blue), and an infiltration of specialized immune cells (green). Credit Salk Institute Usage Restrictions With credit and related coverage 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.