REPLY
We thank Professor Rojas for his insightful comments (1). We purchased the cells from ATCC and are aware that the current HEp2 cell line is a cross-contaminant of a HeLa cell line, as Professor Rojas indicates.
In our paper, HEp2 cells were used as a convenient cell model to compare the relative potencies of test compounds rather than as a model of human respiratory epithelium. We agree with the concern regarding the use of cancer cell lines (such as HEp2, HeLa, and Vero), and we therefore profiled compounds in human air liquid interface (ALI)-cultured fully differentiated bronchial epithelial cells and in a BEAS2B bronchial epithelial cell line as well. The human ALI data clearly confirm the antiviral activity of PC786, and we believe that this model more closely represents the clinical setting. Accordingly, we are presently investigating the antiviral activity of PC786 in the ALI system further (unpublished data).
Footnotes
This is a response to a letter by Rojas (https://doi.org/10.1128/AAC.01823-17).
REFERENCES
- 1.Rojas A. 2017. The imperative authentication of cell lines. Antimicrob Agents Chemother 61:e01823-17. doi: 10.1128/AAC.01823-17. [DOI] [PMC free article] [PubMed] [Google Scholar]