a, Phagocytosis assay for uptake of pHrodo-labelled cells for indicated Cas9-expressing cell lines—Ramos (B cell lymphoma), Karpas-299 (T cell lymphoma), HCT-116 (colorectal 1), RKO (colorectal 2), SKBR3 (breast), OVCAR8 (ovarian), K562 (leukaemia), NCI-H23 (non-small-cell lung carcinoma (NSCLC)), NCI-H82 (small-cell lung carcinoma (SCLC)) and HeLa (cervical)—expressing indicated sgRNAs by J774 macrophages in the presence or absence of anti-CD47 antibodies. Phagocytosis index normalized to control (SafeKO) cells without anti-CD47. Data are mean ± s.d. (n = 4 cell culture wells for all but Karpas-299 and NCI-H82, for which n = 3). One-way ANOVA with Bonferroni correction. b, SafeKO or APMAPKO NCI-H82 cells were transplanted into NSG mice and allowed to form tumours. Mice were treated with anti-CD47 or PBS daily starting 12 d after transplantation, and tumour size was measured every 2 d. Data are mean ± s.e.m. (n = 5). Two-way ANOVA with Tukey correction. c, SafeKO or APMAPKO Ramos cells were transplanted into NSG mice and allowed to form tumours. Mice were treated with anti-CD20 or PBS daily starting 21 d after transplantation, and tumour size was measured every 2 d. Data are mean ± s.e.m. (n = 6 (control groups) or 7 (antibody-treated groups)). Two-way ANOVA with Tukey correction.