Comment on "Tumor-initiating cells establish an IL-33-TGF-{beta} niche signaling loop to promote cancer progression"

Taniguchi et al. (Research Articles, 17 July 2020, p. 269) claim that the cytokine interleukin-33 induces accumulation of tumor-associated macrophages expressing the immunoglobulin E receptor FcRI. Although these findings hold great therapeutic promise, we provide evidence that the anti-FcRI antibody used in this study is not specific for FcRI on macrophages, which raises concerns about the validity of some of the conclusions.