Reply to the Letter to the Editor: Administration of TGF-ß Inhibitor Mitigates Radiation-induced Fibrosis in a Mouse Model

To the Editor,

On behalf of my coauthors, I would like to thank Zhu et al. [2] for their letter to the editor regarding our study, “Administration of TGF-ß Inhibitor Mitigates Radiation-induced Fibrosis in a Mouse Model” [1]. After reading their letter, I will like to include some additional details from our study.

On average, the 12-week-old male mice (n = 28) weighed approximately 27 g upon purchase. While preparing our vehicle, we diluted the dimethyl sulfoxide (DMSO) to a concentration of approximately 10% (one part DMSO diluted in nine parts phosphate-buffered saline solution [PBS]). Per injection, on average, we used 0.0011 mL of DMSO. The solution we injected in transforming growth factor beta (TGF-β) mice was (per injection): 0.03 mg TGF-beta + 0.0011 mL DMSO + 0.01 mL PBS. The solution we injected in the control mice was (per injection): 0.0011 mL DMSO + 0.01 mL PBS.

As you can see, we used a much lower concentration and total amount per injection of DMSO per mouse/kg of mouse than any of the studies referenced in your letter. We apologize if our methods did not make this clear. Unfortunately, we did not document weight loss, decreased appetite, or liver/kidney dysfunction, as this was not part of the scope of our study. We agree that pure DMSO should not be used, and as such, we titrated the concentration appropriately.