## Replication Study: The CD47-signal regulatory protein alpha (SIRPa) interaction is a therapeutic target for human solid tumors <br> **Abstract:** In 2015, as part of the [Reproducibility Project: Cancer Biology][1], we published a Registered Report ([Chroscinski et al., 2015][2]), that described how we intended to replicate selected experiments from the paper “The CD47-signal regulatory protein alpha (SIRPa) interaction is a therapeutic target for human solid tumors“ ([Willingham et al., 2012][3]). Here we report the results of those experiments. We found that treatment of immune competent mice bearing orthotopic breast tumors with anti-mouse CD47 antibodies resulted in short-term anemia compared to controls, consistent with the previously described function of CD47 in normal phagocytosis of aging red blood cells and results reported in the original study (Table S4; [Willingham et al., 2012][4]). The weight of tumors after 30 days administration of anti-CD47 antibodies or IgG isotype control were not found to be statistically different, whereas the original study reported inhibition of tumor growth with anti-CD47 treatment (Figure 6A,B; [Willingham et al., 2012][5]). Additionally, the excised tumors were scored for inflammatory cell infiltrates. Both IgG and anti-CD47 treated tumors resulted in minimal to moderate lymphocytic infiltrate, while neutrophilic infiltration was slightly increased in anti-CD47 treated tumors, while the original study observed sparse lymphocytic infiltrate in IgG-treated tumors and increased inflammatory cell infiltrates in anti-CD47 treated tumors (Figure 6C; [Willingham et al., 2012][6]). Finally, we report a meta-analysis of the result. ---------- ### Contents **Reports:** Read the [Replication Study][7], or view the [preprint versions][8]. To reproduce the Replication Study manuscript text run this in [R Studio][9] (note: downloads [R markdown file][10] directly from osf.io): library(httr) library(rmarkdown) GET("https://osf.io/bsefc/?action=download", write_disk("Replication_Study_39.Rmd", overwrite = T)) render("Replication_Study_39.Rmd", output_format = "word_document") <br> Also, explore the [Registered Report][11] and materials related to the Registered Report [here][12]. <br> **Experiments replicated:** Reproduce and explore the figures, analyses, data, and methods generated in this replication attempt. - [Engraftment of mouse breast cancer cells and treatment with CD47 targeted antibodies][13] - Replication of Figures 6A-C and Table S4 in Willingham et al., 2012. <br> **Meta-analyses:** As a measure of evaluating reproducibility a meta-analysis of each effect was performed. The forest plots, analyses, and data are available [here][14]. <br> Questions about the project can be directed to [contact+rpcb@cos.io][15]. [1]: https://osf.io/e81xl/wiki/home/ [2]: http://elifesciences.org/content/4/e04586v1 [3]: http://www.pnas.org/content/109/17/6662 [4]: http://www.pnas.org/content/109/17/6662 [5]: http://www.pnas.org/content/109/17/6662 [6]: http://www.pnas.org/content/109/17/6662 [7]: http://dx.doi.org/10.7554/eLife.18173 [8]: https://osf.io/hfk42/ [9]: https://www.rstudio.com [10]: https://osf.io/bsefc/ [11]: https://elifesciences.org/content/4/e04586 [12]: https://osf.io/tbr62/wiki/home/ [13]: https://osf.io/g57ch/wiki/home/ [14]: https://osf.io/ha2bx/wiki/home/ [15]: mailto:contact+rpcb@cos.io