Effect of Dexamethasone on the Expression of the α2,3 and α2,6 Sialic Acids in Epithelial Cell Lines

Round 1

Reviewer 1 Report

The manuscript pathogens-2010788 Effect of dexamethasone on the expression of the α2,3 and α2,6 sialic acid in epithelial cell lines by Onasis Vicente-Fermín et al. describes the effect of dexamethasone on the expression of Siaα2,3 and Siaα2,6 under conditions of viral inflammation. The topic of the study is indeed important and interesting.

The manuscript is logical and well written. The prospects for the practical use of the results obtained are high. The paper will definitely be of interest to the readers of Pathogens.

Questions and comments:

1) The introduction is too short. The complex mechanism of action of dexamethasone and its various pharmacological effects should be described (doi.org/10.3390/biomedicines9040341). 

2) The use of human respiratory tract cells to model viral inflammation is reasonable. How appropriate to use canine and monkey kidney cell lines in this study? 

3)  Which form of dexamethasone (water-insoluble base or water-soluble dexamethasone phosphate salt) did you use? If you used water-insoluble dexamethasone, you should specify which solvent was used, because the nature of the solvent may have affected the cellular experiment.

4) The figures are inexpressive and poorly readable. The quality of the figures should be improved. 

Author Response

1) The introduction is too short. The complex mechanism of action of dexamethasone and its various pharmacological effects should be described (doi.org/10.3390/biomedicines9040341). 

Thank you for your comment. Pharmacological effects and mechanisms of action of dexamethasone have been added to Introduction (lines 45-57).

 

2) The use of human respiratory tract cells to model viral inflammation is reasonable. How appropriate to use canine and monkey kidney cell lines in this study? 

MDCK and Vero cells are widely used for the study of the virus mechanisms of entry, as well as for its growing in vitro, as an alternative to the allantoic cavity of embryonated chicken eggs [Gambaryan et al. 1999; Genzel et al. 2010; Murakami et al. 2012]. This comment has been added to Introduction (lines 79-82).

 

3)  Which form of dexamethasone (water-insoluble base or water-soluble dexamethasone phosphate salt) did you use? If you used water-insoluble dexamethasone, you should specify which solvent was used, because the nature of the solvent may have affected the cellular experiment.

Dexamethasone phosphate was used in this study. This has been mentioned in Material and Methods (line 314). 

 

4) The figures are inexpressive and poorly readable. The quality of the figures should be improved. 

The quality of all figures has been improved. 

Reviewer 2 Report

Comments for the authors:

Huerta et al proposed a two -color flow cytometry assay for the specific and simultaneous detection of the expression of Galb1-3GalNAc and Siaa2,3 or Siaa2,6 glycans on three cell lines which are widely used for influenza research. The assay used neuraminidase and fetuin (lectin absorption) to confirm the specific of the test and revealed that MDCK.2 cells contain two subpopulations harboring slightly different levels of expression of and Siaa2,3 or Siaa2,6. The authors further compared the effect of dexamethasone on the expression of sialyl residues in the three cell lines, and found that dexamethasone completely abolished the expression of Siaa2,3 whereas it slightly increased the expression or Siaa2,6 in these cells. The analysis is information-rich and I provide some comments for the author’s consideration:

1. The introduction serves as a nice background for reader.

 

2. The manuscript overall provided sufficient detail on methods, results and the author’s insights. For the flow cytometric analysis method description, it would be clearer for readers if the authors can provide more details or flow chart for the process, e.g. which lectin with which fluorochrome produced which color signal and indicated which sialyl residue. 

Author Response

1. The introduction serves as a nice background for reader.

Thank you for your comment.

 

2. The manuscript overall provided sufficient detail on methods, results and the author’s insights. For the flow cytometric analysis method description, it would be clearer for readers if the authors can provide more details or flow chart for the process, e.g. which lectin with which fluorochrome produced which color signal and indicated which sialyl residue.

 

Thank you for this suggestion. A table has been included to indicate the lectin type, the corresponding fluorochrome, the color signal produced, the recognized sialyl residue, and manufacturer.

Round 2

Reviewer 1 Report

The article may be accepted.