**Figure 1. Blood toxicity analysis.** Female FVB mice bearing orthotopic MT1A2 breast tumors were randomized to receive IgG isotype control (IgG) (n=7) or anti-mouse CD47 (CD47) (n=7) antibodies. Mice bearing small or undetectable tumors were designated for baseline reading (NT) (n=6). Five days after the beginning of treatment blood samples collected via retro-orbital bleed were analyzed on a hematology analyzer. Dot plots with means reported as crossbars for each hematological parameter. For each parameter a one-way ANOVA was performed and the alpha level or p-value was adjusted using the Bonferroni correction. (**A**) White blood cells (WBC), one-way ANOVA; *F*(2,17) = 15.09, uncorrected *p* = .00017 with alpha level = .0033; (Bonferroni corrected *p* = .0026). (**B**) Neutrophils (NE), one-way ANOVA; *F*(2,17) = 1.02, uncorrected *p* = .381 with alpha level = .0033; (Bonferroni corrected *p* > .99). (**C**) Lymphocytes (LY), one-way ANOVA; *F*(2,17) = 20.84, uncorrected *p* = 2.67x10^-5 with alpha level = .0033; (Bonferroni corrected *p* = .00040). (**D**) Monocytes (MO), Welch's one-way ANOVA; *F*(2,8.52) = 9.98, uncorrected *p* = .0058 with alpha level = .0033; (Bonferroni corrected *p* = .0877). (**E**) Eosinophils (EO), one-way ANOVA; *F*(2,17) = 0.06, uncorrected *p* = .942 with alpha level = .0033; (Bonferroni corrected *p* > .99). (**F**) Basophils (BA), one-way ANOVA; *F*(2,17) = 4.20, uncorrected *p* = .0330 with alpha level = .0033; (Bonferroni corrected *p* = .495). (**G**) Red blood cells (RBC), one-way ANOVA; *F*(2,17) = 424.9, uncorrected *p* = 3x10^-15 with alpha level = .0033; (Bonferroni corrected *p* = 5xo^-14). (**H**) Hemoglobin (Hb), one-way ANOVA; *F*(2,17) = 502.1, uncorrected *p* = 8xo^-16 with alpha level = .0033; (Bonferroni corrected *p* = 1x10^-14). (**I**) Hematocrit (HCT), one-way ANOVA; *F*(2,17) = 283.0, uncorrected *p* = 9x10^-14 with alpha level = .0033; (Bonferroni corrected *p* = 1x10^-12). (**J**) Mean corpuscular volume (MCV), one-way ANOVA; *F*(2,17) = 11.81, uncorrected *p* = .00061 with alpha level = .0033; (Bonferroni corrected *p* = .0091). (**K**) Mean corpuscular hemoglobin (MCH), one-way ANOVA; *F*(2,17) = 10.64, uncorrected *p* = .00101 with alpha level = .0033; (Bonferroni corrected *p* = .0151). (**L**) Mean corpuscular hemoglobin concentration (MCHC), one-way ANOVA; *F*(2,17) = 0.61, uncorrected *p* = .552 with alpha level = .0033; (Bonferroni corrected *p* > .99). (**M**) Red blood cell distribution width (RDW), Welch's one-way ANOVA; *F*(2,10.46) = 30.62, uncorrected *p* = 4.25x10^-5 with alpha level = .0033; (Bonferroni corrected *p* = .00064). (**N**) Platelets (PLT), one-way ANOVA; *F*(2,17) = 0.62, uncorrected *p* = .548 with alpha level = .0033; (Bonferroni corrected *p* > .99). (**O**) Mean platelet volume (MPV), one-way ANOVA; *F*(2,17) = 6.98, uncorrected *p* = .0061 with alpha level = .0033; (Bonferroni corrected *p* = .092). Access [full size image][1] and [R script][2] used to generate this figure. This script will call the [data][3] directly from the OSF. <br> **Figure 1 - figure supplement 1. Blood toxicity analysis.** Female FVB mice bearing orthotopic MT1A2 breast tumors were randomized to receive IgG isotype control (IgG) (n=7) or anti-mouse CD47 (CD47) (n=7) antibodies. Mice bearing small or undetectable tumors were designated for baseline reading (NT) (n=6). Five days after the beginning of treatment blood samples collected via retro-orbital bleed were analyzed on a hematology analyzer. Normal reference ranges (Range) for each parameter are from Drew Scientific Hemavet 950FS. WBC = White blood cells; NE = Neutrophils; LY = Lymphocytes; MO = Monocytes; EO = Eosinophils; BA = Basophils; RBC = Red blood cells; Hb = Hemoglobin; HCT = Hematocrit; MCV = Mean corpuscular volume; MCH = Mean corpuscular hemoglobin; MCHC = Mean corpuscular hemoglobin concentration; RDW = Red blood cell distribution width; PLT = Platelets; MPV = Mean platelet volume. Access [full size image][4] and [R script][5] used to generate this figure. This script will call the [data][6] directly from the OSF. <br> **Figure 2. Final tumor weights of immune competent hosts treated with control or CD47 targeted antibodies.** At the end of the predefined study period (Day 31), tumors from mice bearing orthotopic MT1A2 breast tumors treated every other day with IgG isotype control (IgG) (n=7) or anti-mouse CD47 (anti-CD47) (n=6) antibodies were excised and weighed. Dot plot with means reported as crossbars and error bars represent s.e.m. Two-tailed Welch’s *t*-test between IgG and anti-CD47 treated tumors; *t*(9.66) = 1.796, *p* = .104. Access [full size image][7] and [R script][8] used to generate this figure. This script will call the [data][9] directly from the OSF. <br> **Figure 2 - figure supplement 1. Tumor volumes of immune competent hosts treated with control or CD47 targeted antibodies.** This is the same experiment as in Figure 2. Following orthotopic injection of MT1A2 cells mice were monitored for development of tumors. Caliper measurements were taken at 9, 11, 18, and 25 days after cell injection to calculate tumor volume. Fourteen mice with detectable tumors were randomly assigned to treatment at 11 days post cell inoculation (dashed line). At the end of the predefined study period, tumors from mice treated with either IgG isotype control (IgG) (n=7) or anti-mouse CD47 (anti-CD47) (n=6) antibodies were excised and weighed. Tumor volume at day 42 post cell injection was calculated from weight and density (1.05 g/ml). Exploratory analysis on tumor weights excluding three tumors that regressed during the course of the study (indicated by asterisk): two-tailed Welch’s _t_-test between IgG and anti-CD47 treated tumors; _t_(7.94) = 0.745, _p_ = .478, Glass’ ∆ = -0.58, 95% CI [-1.88, 0.80]. Access [full size image][10] and [R markdown file][11] used to generate this figure. This script will call the [data][12] directly from the OSF. <br> **Table 1. Severity of inflammatory cell infiltration of tumors.** Excised tumors were fixed, sectioned, and stained with hematoxylin and eosin and blindly scored by a Board Certified pathologist utilizing the severity score for inflammatory cell infiltrates (Demaria et al., 2001). Tumor infiltrating lymphocytes and neutrophils were scored for tumors from mice bearing orthotopic MT1A2 breast tumors treated every other day with IgG isotype control (IgG) (n=7) or anti-mouse CD47 (CD47) (n=6) antibodies. Access [full size image][13] and [R markdown file][14] used to generate this table. This script will call the [data][15] directly from the OSF. <br> ---------- [Statistical Analyses component][16] contains R scripts that were used for the analysis. [1]: https://osf.io/se2cj/ [2]: https://osf.io/6m34t/ [3]: https://osf.io/qga8h/ [4]: https://osf.io/rtwb7/ [5]: https://osf.io/ke7vt/ [6]: https://osf.io/qga8h/ [7]: https://osf.io/4dyxp/ [8]: https://osf.io/4ktnx/ [9]: https://osf.io/pcruk/ [10]: https://osf.io/nrab8/ [11]: https://osf.io/wb6qs/ [12]: https://osf.io/y3fmz/ [13]: https://osf.io/nvs3u/ [14]: https://osf.io/m8gec/ [15]: https://osf.io/3fy9a/ [16]: https://osf.io/ju36c/wiki/home/