CD47 and cancer: Although the impact of CD47 on anti-cancer immune responses was originally attributed exclusively to its inhibitory effect on macrophage phagocytosis of cancer cells [16, 17, 21], it has been recently demonstrated that CD47 expression in cancer cells has a profound impact on anti-cancer T cell responses [23, 24, 39], as blockade of CD47 primes tumour-specific T cell responses as a consequence of enhanced phagocytosis of tumour cells by macrophages as well as DCs [23, 24, 39].