Placental ACE2 Expression: A Possible Pathogenetic Mechanism for Infantile Hemangiomas

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript by De Marco, Aa. et al. describing the relationship between ACE2 expression, placental weight and occurrence of infantile hemangiomas is a simple but interesting topic. However, there are some major issues:

- There is an issue with the introduction section, particularly the first paragraph. This is very difficult to read / understand for different reasons. You should begin defining the bigger matter (in this case the renin-angiotensin system). After the introduction of this system, including the general role(s) of angiotensin, you can define the angiotensin I and II. Then (may be in another paragraph), you can introduce ACE2 and define the hidrolized angiotensins. By the way, I suggest (only suggest) to reconsider the acronyms in this paragraph, may be you can just simplify them by stating (Ang) after the first mention of angiotensin (in this case would be “hydrolyzing angiotensin (Ang) I and Ang II in Ang-(1-9) and Ang-(1-7)” in lines 39-42.

- I miss a deeper explanation of the employed materials and methods. For example, you don´t mention how the immunohistochemistry was performed (i.e. did you used an automatized platform or performed it manually). In addition, the number and distribution of the different studied cases (this is the “materials”!!) are only mentioned at the beginning of the results section. Please, be scientifically sound and put each part of the manuscript in its place.

In addition, there are various minor comments:

- Abstract, page 1, line 23. Although mentioned in the title, you should repeat here the meaning of IH.                                                                         

- Introduction, page 4, Figure 2. Images are fine, but are displayed in a somewhat overlapping manner. Please, separate them with a thin blank space and include a fine line surrounding each image. There is no specification about the measure of the different scale bars. You may consider including the image in Figure 1 with these to simplify.

- Materials and methods, page 4, lines 96-98. Please reformulate this sentence.

- Materials and methods, page 4, line 104. HI?

- Results, page 7, Figures 3-5. These 2 images and the resuming graph should be the same figure with 3 subsections. Figures 4 and 5 should have a scale bar. The scale bar should also state the expression score given to each image.

- Discussion, page 8, lines 183-188. Please, reformulate this complex sentence.

- Discussion, page 9, lines 221-223. Please, reformulate this sentence. As is the case?

- Discussion, page 9, line 225. No other significant (or relevant) differences. ACE2 expression may be considered an histological parameter. Please, reformulate this long sentence. May be you should talk about chorioamnionitis before of the sentence discarding (other) histological relationships.

Comments on the Quality of English Language

Language is generally fine, with some long sentences and various minor issues.

Author Response

Comments 1: 

There is an issue with the introduction section, particularly the first paragraph. This is very difficult to read / understand for different reasons. You should begin defining the bigger matter (in this case the renin-angiotensin system). After the introduction of this system, including the general role(s) of angiotensin, you can define the angiotensin I and II. Then (may be in another paragraph), you can introduce ACE2 and define the hidrolized angiotensins. By the way, I suggest (only suggest) to reconsider the acronyms in this paragraph, may be you can just simplify them by stating (Ang) after the first mention of angiotensin (in this case would be “hydrolyzing angiotensin (Ang) I and Ang II in Ang-(1-9) and Ang-(1-7)” in lines 39-42.

Answer n'1: Thank you very much dear Reviewer n'1 for your useful tips to improve the quality of our manuscript. We have improved this part of paper.

Reviewer n'1: - I miss a deeper explanation of the employed materials and methods. For example, you don´t mention how the immunohistochemistry was performed (i.e. did you used an automatized platform or performed it manually).

Answer n'2: Thank you very much. We have added this information in Material and Methods section.

Reviewer n'1: In addition, the number and distribution of the different studied cases (this is the “materials”!!) are only mentioned at the beginning of the results section. Please, be scientifically sound and put each part of the manuscript in its place.

Answer n'3: Thank you. All done.

Reviewer n'1: - Abstract, page 1, line 23. Although mentioned in the title, you should repeat here the meaning of IH.        

Answer n'4: Done. Thanks again.

Reviewer n'1:              

• Introduction, page 4, Figure 2. Images are fine, but are displayed in a somewhat overlapping manner. Please, separate them with a thin blank space and include a fine line surrounding each image. There is no specification about the measure of the different scale bars. You may consider including the image in Figure 1 with these to simplify.

Answer n'4: Thank you. Done.

Reviewer n'1: 

- Materials and methods, page 4, lines 96-98. Please reformulate this sentence.

- Materials and methods, page 4, line 104. HI?

• Results, page 7, Figures 3-5. These 2 images and the resuming graph should be the same figure with 3 subsections. Figures 4 and 5 should have a scale bar. The scale bar should also state the expression score given to each image.

Answer n'5: Done. Thank you.

Reviewer n'1: 

- Discussion, page 8, lines 183-188. Please, reformulate this complex sentence.

- Discussion, page 9, lines 221-223. Please, reformulate this sentence. As is the case?

• Discussion, page 9, line 225. No other significant (or relevant) differences. ACE2 expression may be considered an histological parameter. Please, reformulate this long sentence. May be you should talk about chorioamnionitis before of the sentence discarding (other) histological relationships.

Answer n'6: done. Thank you.

Reviewer 2 Report

Comments and Suggestions for Authors

The work of the authors is very interesting and I have no major issues to raise, only some minor points:

- please report better in the Methods section about the control group: were the control placentas selected only by matching gestational age? Or were there other factors which were controlled for (diabetes, hypertension, previous history of these conditions  and so on)

- please add in the Methods what positive and negative controls were used for immunohistochemistry of ACE2

- please check the manuscript throughout for typos and blank spaces (e.g infantile hemangiomas IH is somewhere written aa HI eg. line 104; blank spaces in line 110 and so on)

Author Response

Comments 1: 

- please report better in the Methods section about the control group: were the control placentas selected only by matching gestational age? Or were there other factors which were controlled for (diabetes, hypertension, previous history of these conditions  and so on)

- please add in the Methods what positive and negative controls were used for immunohistochemistry of ACE2

• please check the manuscript throughout for typos and blank spaces (e.g infantile hemangiomas IH is somewhere written aa HI eg. line 104; blank spaces in line 110 and so on).

Answer n'1: Thank you for everything. All done.