Cells on the Lookout (image) NIH/National Institute of Neurological Disorders and Stroke Share Print E-Mail Caption Meningeal macrophages (shown in white, red, and blue) are on constant alert against potential threats to brain tissue. Credit Image courtesy of the McGavern Lab, NINDS. Usage Restrictions For educational use only. Share Print E-Mail 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.