Contents

15 September 2020
Vol 13, Issue 649

About The Cover

Cover image expansion

Online Cover This week features a Research Article that shows that signaling by the inhibitory receptor PD-1 on tumor-infiltrating lymphocytes interferes with their ability to form stable contacts with their target tumor cells, thus impairing tumor cell killing. The image is a scanning electron micrograph of a tumor showing tumor cells (red), blood vessels (yellow), and tumor-infiltrating lymphocytes (white). [Image: Eye of Science/Science Source]