Correction to: Cell research https://doi.org/10.1038/s41422-020-0277-x, published online 23 January 2020

We apologize for a mistake in Fig. 2 that we just identified in our manuscript published online on January 23, 2020. On the top right of the figure the crosses and question marks do not correspond to the correct molecules. CTLA-4 and PD-1 should have the cross and the other 3 receptors the question marks. The correct version of Fig. 2 is shown below. The correction does not affect the description and conclusion of this review.