The Expression of Vitamin D Receptor on Peripheral Blood Mononuclear Cells in Patients with Psoriasis

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The study focuses on the expression of vitamin D receptors (VDR) on mononuclear cells in psoriasis patients, which is a significant topic considering the known link between vitamin D and autoimmune diseases like psoriasis.

The study focuses on the expression of vitamin D receptors (VDR) on mononuclear cells in psoriasis patients, which is a significant topic considering the known link between vitamin D and autoimmune diseases like psoriasis.

The p-values in some sections (e.g., VDR expression on CD3+ lymphocytes, p = 0.83) suggest no statistically significant differences. Yet, the conclusions sometimes imply clinical relevance.

The study found higher baseline levels of 25(OH)D in psoriasis patients than in controls, which seems counterintuitive.

VDR expression on CD14+ cells increased in healthy controls over time without intervention. This is an unusual finding.

The study found no correlation between PASI score (psoriasis severity) and VDR expression on mononuclear cells, yet VDR expression in skin has been correlated with PASI in other studies.

A more detailed discussion of how the small sample size may affect the robustness of the conclusions would strengthen the manuscript. Ensure the discussion accurately reflects the implications of non-significant findings to avoid overstating the conclusions. 

Comments on the Quality of English Language

The quality of the English language in the manuscript is generally good but could benefit from further refinement for clarity and precision

Author Response

Authors’ Reply to the Reviewer Report (Reviewer 1)

The study focuses on the expression of vitamin D receptors (VDR) on mononuclear cells in psoriasis, which is a significant topic considering the known link between vitamin D and autoimmune diseases like psoriasis.

Comment 1: The p-values in some sections (e.g., VDR expression on CD3+ lymphocytes, p = 0.83) suggest no statistically significant differences. Yet, the conclusions sometimes imply clinical relevance.

Response 1: Thank you for pointing this out, we agree. We have looked this over and made some adjustments in the text regarding the results. We have adjusted the sentence in the results on page 5, under 3.2 sentence 170-171.

Comment 2: The study found higher baseline levels of 25(OH)D in psoriasis patients than in controls, which seems counterintuitive.

Response 2: Thank you for your comment and we understand the importance of this and we have added another references in the discussion, a meta-analysis ,that reported lower levels of 25(OH)D in patients with psoriasis to highlight that this contrasts with our finding which can be found on page 11, sentence 346-348, as well as we have added other references that did not show any significant differences in serum vitamin D levels between psoriasis patients and controls, page 11, sentence 348-355.

Comment 3: VDR expression on CD14+ cells increased in healthy controls over time without intervention. This is an unusual finding.

Response 3: Thank you and we agree to this, as discussed in the article sentences 259-263 page 10.The small sample size as well as the fact that the study was conducted over the entire calendar year, introducing seasonal variations, as well as a great individual variation in the expression on the expression of VDR on the immune cells, could all affect the results as stated in sentence 356-362 on page 12.

Comment 4: The study found no correlation between PASI score (psoriasis severity) and VDR expression on mononuclear cells, yet VDR expression in skin has been correlated with PASI in other studies.

Response 4: Thank you for this comment and that is correct, we have mentioned this in the discussion part as well as we have stated that this does not align with the findings in our study, page 11, sentence 321-331. The expression of VDR on mononuclear blood cells might be influenced by different and more strongly by some factors except from the severity of inflammation, that we perhaps yet are still unaware of compared to the skin, but this is also another reason of why further research is necessary in the topic as stated in the manuscript, page 11, sentence 334-335. The small sample size could of course also lead to confounding factors influencing the results in our study, which we have added to the article, page 12, sentence 356-361.

Comment 5: A more detailed discussion of how the small sample size may affect the robustness of the conclusions would strengthen the manuscript. Ensure the discussion accurately reflects the implications of non-significant findings to avoid overstating the conclusions. 

Response 5: Thank you for this feedback and changes has been made accordingly. Information about absence of correlation between serum vitamin D levels and the expression of VDR on PBMCs has been clarified in page 10, sentence 259-263, even though our observations suggests that total and free 25(OH)D levels regulate the expression of VDR on the analyzed immune cells, both at baseline I the psoriasis cohort and after 24 week follow up among the healthy controls. As well as sentence 308-309 on page 11 has been adjusted to clarify the same thing, as well as page 12 sentence 372-377 in the conclusion. We have also adjusted a part of the results section, as mentioned in comment 1, on page 5, under 3.2 sentence 170-171. In our study there were great individual variations in the expression of VDR (%) on both CD3+ cells and CD14+ cells in both patients with psoriasis and healthy controls, both at baseline and after 24 weeks. Min-Max expression of VDR (%) on CD3+ cells in patients with psoriasis was 0.09-37 before treatment and 0.09-47 after treatment and for healthy controls 0.18-25 at baseline and 0.03-27 after 24 weeks. Min-Max expression of VDR (%) on CD14+ cells in patients with psoriasis was 9.5-99 before treatment and 0.06-100 after treatment and for healthy controls 2.6-27 at baseline and 9,6-48 after 24 weeks. With our small sample size, which is a limitation of our study, this great individual variations in the expressions of VDR could influence our results and a larger sample size could be beneficial for significant results. We have added this to the discussion which can be found on page 12, sentence 356-362.

Comment 6: The quality of the English language in the manuscript is generally good but could benefit from further refinement for clarity and precision.

Response 6: We have looked over the language in the manuscript and we hope that you will find it suitable.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

 

The manuscript by Zanghaneh et al. presents findings on VDR expression in PBMC cells from both healthy individuals and psoriatic patients treated with Etanercept. Although the results are negative, they are nonetheless valuable to the scientific literature. Overall, the article is well-written, with the authors appropriately addressing the study's limitations and discussing relevant literature.

 

Major:

However, given that VDR is known to suppress the release of Th17 cytokines, cells that contribute to psoriasis, it would be beneficial for the authors to measure IL-17 levels in the analyzed samples using ELISA.

Minor:

1.      Please clarify the role of VDR in Th17 cells by citing relevant literature. Additionally, provide a more detailed explanation of the role these cells play in psoriasis.

2.      Page 5 Lines 165-166 “The expression of VDR on CD3+ lymphocytes were higher in patients with psoriasis compared to healthy controls at baseline, but the difference was not significant (p = 0.83).” Since the results were not statistically significant, this indicates that the expression did not differ. Please revise this statement accordingly.

3.      Figure 2. Please indicate the statistical significance directly on the plot.

4.      Page 11. “The main limitation of this study is the small number of participants. Additionally, the study was conducted throughout the entire calendar year, introducing seasonal variations that might impact the results.” To support this claim please cite recently published paper: https://doi.org/10.3389/abp.2024.13108

Author Response

Authors’ Reply to the Reviewer Report (Reviewer 2)

The manuscript by Zanghaneh et al. presents findings on VDR expression in PBMC cells from both healthy individuals and psoriatic patients treated with Etanercept. Although the results are negative, they are nonetheless valuable to the scientific literature. Overall, the article is well-written, with the authors appropriately addressing the study's limitations and discussing relevant literature.

 

Major:

Comment 1: However, given that VDR is known to suppress the release of Th17 cytokines, cells that contribute to psoriasis, it would be beneficial for the authors to measure IL-17 levels in the analyzed samples using ELISA.

Response 1: Thank you for this valuable input and we agree that it would been of great interest to perform this analysis, unfortunately we don’t have the possibility to perform this analysis since all data is already gathered and all analysis are already made.

Minor:

Comment 2: Please clarify the role of VDR in Th17 cells by citing relevant literature. Additionally, provide a more detailed explanation of the role these cells play in psoriasis.

Response 2: Thank you for this comment and thank you for pointing this out. It has been added on page 1, sentence 38-42 and page 2, sentence 69-72. As well as some of the text have been removed on page 1 sentence 43-45.

Comment 3: Page 5 Lines 165-166 “The expression of VDR on CD3+ lymphocytes were higher in patients with psoriasis compared to healthy controls at baseline, but the difference was not significant (p = 0.83).” Since the results were not statistically significant, this indicates that the expression did not differ. Please revise this statement accordingly.

Response 3: Thank you for pointing this out, adjustments has been done accordingly in the text on page 5, under 3.2 sentence 170-171.

Comment 4: Figure 2. Please indicate the statistical significance directly on the plot.

Response 4: Thank you for this valuable input. We have adjusted figure 2 accordingly, page 8 and made the same adjustment on figure 1, page 7.

Comment 5: Page 11. “The main limitation of this study is the small number of participants. Additionally, the study was conducted throughout the entire calendar year, introducing seasonal variations that might impact the results.” To support this claim please cite recently published paper: https://doi.org/10.3389/abp.2024.13108

Response 5: Thank you for this recommendation and we have read this article and it’s suitable for a reference in our article and it has been added as a reference on page 12, sentence 361-362.

 

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

No further comments, the authors addressed all concerns.