Circulating Interleukin-22 in Patients with Acute Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

 Article Title:

Circulating Interleukin-22 in Patients with Acute Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

Authors:

Augusto F. Correia, Carolina G. C. Oliveira, Dinaldo C. O. Jr., Michelly C. Pereira, Flavio A. Carvalho, Estevão C. C. Martins, Dinaldo C. Oliveira

Journal:

Journal of Clinical Medicine

 

Brief Summary

This article examines the levels of circulating interleukin-22 (IL-22) in patients with acute ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI) compared to healthy controls. It also explores associations between IL-22 levels and clinical parameters such as the culprit coronary artery, door-to-balloon time (DBT), angiographic results, CAD classification, and diabetes mellitus (DM).

General Concept Comments

Strengths:

• The study addresses a significant and relevant clinical issue, exploring a potential new coronary artery disease (CAD) biomarker.
• The methodology is detailed, and the study design is appropriate for the research question.
• The article is well-structured and the data are clearly presented.

Weaknesses:

• The single-center design may limit the generalizability of the findings.
• The study only measures IL-22 levels at a single time point, which may not capture the full dynamics of IL-22 in STEMI patients.
• There is a lack of data on the prognostic value of IL-22 levels due to the low rate of clinical events after PPCI.

Specific Comments

Introduction:

• The introduction provides a good overview of the significance of cardiovascular diseases and the potential role of IL-22 in CAD. However, it could benefit from a more detailed discussion on previous findings regarding IL-22 in various stages of CAD and myocardial infarction.

Materials and Methods:

• The study design is appropriate, and the inclusion/exclusion criteria are clearly defined.
• The methods for IL-22 measurement and statistical analysis are well described. However, more details on the rationale for choosing specific cutoffs (e.g., DBT ≤ 60 minutes) would be beneficial.

Results:

• The results are presented clearly, with appropriate use of tables to summarize the data.
• The finding of lower IL-22 levels in STEMI patients compared to controls is intriguing. The subgroup analyses provide additional insights but should be interpreted cautiously due to potential confounding factors.

Discussion:

• The discussion adequately covers the main findings but could be expanded to include more comparisons with existing literature. The potential mechanisms underlying the observed associations between IL-22 levels and clinical parameters should be explored more deeply.
• The limitations section is concise but could discuss more potential biases and confounders, such as the impact of medications on IL-22 levels.

Conclusions:

• The conclusions are consistent with the data presented and highlight the potential of IL-22 as a biomarker in STEMI. However, more specific recommendations for future research and clinical practice would strengthen the conclusion.

 

Author Response

Review 1

Specific Comments

Introduction:

• The introduction provides a good overview of the significance of cardiovascular diseases and the potential role of IL-22 in CAD. However, it could benefit from a more detailed discussion on previous findings regarding IL-22 in various stages of CAD and myocardial infarction.  We understand your suggested, but we should talk that is this kind of patients (STEMI who underwent primary percutaneous coronary intervention) we did not find data about IL 22. So, we focus on this kind o patients

Materials and Methods:

• The study design is appropriate, and the inclusion/exclusion criteria are clearly defined.
• The methods for IL-22 measurement and statistical analysis are well described. However, more details on the rationale for choosing specific cutoffs (e.g., DBT ≤ 60 minutes) would be beneficial.  Explained OK

Results:

• The results are presented clearly, with appropriate use of tables to summarize the data.
• The finding of lower IL-22 levels in STEMI patients compared to controls is intriguing. The subgroup analyses provide additional insights but should be interpreted cautiously due to potential confounding factors. Agree (only hypothesis)

Discussion:

• The discussion adequately covers the main findings but could be expanded to include more comparisons with existing literature. The potential mechanisms underlying the observed associations between IL-22 levels and clinical parameters should be explored more deeply. Studies like our study, ie studies that only enrolled patients with STEMI who underwent primary percutaneous coronary intervention as reperfusion strategy and evaluated circulating IL 22 are not available according to our search. We did nor find study like our study as well. As told before we try to focus on this kind os scenario (to show evidence)

 

• The limitations section is concise but could discuss more potential biases and confounders, such as the impact of medications on IL-22 levels. We added. OK

Conclusions:

• The conclusions are consistent with the data presented and highlight the potential of IL-22 as a biomarker in STEMI. However, more specific recommendations for future research and clinical practice would strengthen the conclusion.

Additional researches with follow up will be useful to understand  the role of the IL22 in patients with acute myocardial infarction who underwent PPCI. OK

 

 

 

 

 

 

Reviewer 2 Report

Comments and Suggestions for Authors

I am grateful to the editor for the opportunity to review the manuscript of Augusto F. Correia et al "Circulating interleukin-22 in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention". In this article, the authors assessed the level of circulating interleukin-22 in patients with acute myocardial infarction. A feature of the main group was the presence of acute ST-elevation myocardial infarction and percutaneous coronary intervention. As a result, new data were obtained that are radically different from the previously obtained results. This is difficult to interpret, and this raises questions and comments about the text of the manuscript:

1. The article does not contain characteristics of the control group. Was she comparable to the main group in age and gender? Perhaps the observed differences in IL-22 levels are due to the younger age in the control group?

2. The authors explain the differences in data with the previous study (link 17 in the article) by differences in the clinical characteristics of patients with myocardial infarction (in the article these are patients with STEMI undergoing PPCI, in the previous study - patients with NSTEMI and without PCI). However, the text of the article by Zhang L et al (ref. 17) does not provide the characteristics of the included patients with AMI; there is no direct indication that these were patients with NSTEMI. In addition, all other forms of CAD showed higher levels of IL-22 than healthy controls. The authors need to explain in more detail the reasons for this decrease in IL-22 levels in the cohort of patients they studied.

3. Analysis of data in subgroups also raises questions. First, it is unclear how the significance of differences between the three subgroups with different culprit arteries was assessed. Apparently, the distribution of data in these subgroups was not normal, so it was necessary to use the Kruskal-Wallace test. However, in section 2.2. Statistical analysis There is no mention of this analysis method. Secondly, how can the lower IL-22 values ​​in the culprit artery RCA and ADA subgroups compared with CXA be interpreted? This issue is not discussed in the text of the manuscript.

4. In subgroups with different door-to-balloon time values, a decrease in IL-22 was noted in the subgroup with DBT ≤ 60 minutes compared to the subgroup > 60 minutes. How can this data be interpreted? Typically, a decrease in DBT is associated with an improvement in the clinical course and prognosis of AMI. Does this mean that the decrease in IL-22 indicates the same thing? How does this compare with the literature?

5. Line 102 "red by the author (2022)." - it's a typo?

Comments on the Quality of English Language

I believe that the manuscript should be edited by a native English speaker

Author Response

1. The article does not contain characteristics of the control group. Was she comparable to the main group in age and gender? Perhaps the observed differences in IL-22 levels are due to the younger age in the control group? We did
2. The authors explain the differences in data with the previous study (link 17 in the article) by differences in the clinical characteristics of patients with myocardial infarction (in the article these are patients with STEMI undergoing PPCI, in the previous study - patients with NSTEMI and without PCI). However, the text of the article by Zhang L et al (ref. 17) does not provide the characteristics of the included patients with AMI; there is no direct indication that these were patients with NSTEMI. In addition, all other forms of CAD showed higher levels of IL-22 than healthy controls. The authors need to explain in more detail the reasons for this decrease in IL-22 levels in the cohort of patients they studied.

Clinical characteristics mean clinical presentation, ie NSTEMI and STEMI.  Different from other studies our study enrolled patients with STEMI that undewent PPCI and we found lower levels of IL22. So, it is possible that this kind of reperfusion strategy (PPCI) leads to this difference. OK

 

3. Analysis of data in subgroups also raises questions. First, it is unclear how the significance of differences between the three subgroups with different culprit arteries was assessed. Apparently, the distribution of data in these subgroups was not normal, so it was necessary to use the Kruskal-Wallace test. However, in section 2.2. Statistical analysis There is no mention of this analysis method. Secondly, how can the lower IL-22 values ​​in the culprit artery RCA and ADA subgroups compared with CXA be interpreted? This issue is not discussed in the text of the manuscript. We added Kruskal Wallis test and explanation about the findings. OK

 

4. In subgroups with different door-to-balloon time values, a decrease in IL-22 was noted in the subgroup with DBT ≤ 60 minutes compared to the subgroup > 60 minutes. How can this data be interpreted? Typically, a decrease in DBT is associated with an improvement in the clinical course and prognosis of AMI. Does this mean that the decrease in IL-22 indicates the same thing? How does this compare with the literature?

DBT less than 60 minutes and RCA infarction are associated with better prognosis. Our data revealed that the circulating IL 22 levels were lower in patients with DBT less than 60 minutes and with RCA culprit artery, so it is possible that in this king of patients the lower levels of circulating IL 22 have a protective effect. However, we did not evaluate prognosis what allow us only to suggest a hypothesis.

 

 

 

Reviewer 3 Report

Comments and Suggestions for Authors

Circulating interleukin-22 in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention

 

The manuscript titled “Circulating interleukin-22 in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention ” by Correia et al. is an interesting work. Acute coronary syndrome (ACS) is the most severe form of coronary artery disease (CAD) and is associated with a particularly poor prognosis. Primary percutaneous coronary intervention (PPCI) is critical in cases of acute ST-elevation myocardial infarction (STEMI). Interleukin-22 (IL-22) may serve as a novel biomarker for CAD due to its role in signaling and regulating immune and inflammatory responses. This study investigated the differences in circulating IL-22 levels between STEMI patients undergoing PPCI and healthy controls. The findings revealed that IL-22 levels were significantly lower in STEMI patients compared to healthy controls. Additionally, within the STEMI subgroup, patients with a door-to-balloon time (DBT) of less than 60 minutes and those with the right coronary artery (RCA) as the culprit artery had even lower IL-22 levels.

 

 

Overall, the information presented in this manuscript is useful and I approve its publication after some major updates. 

Major comments: I suggest that these comments be updated before publication.

a. Moderate improvement in English language usage is needed.

b. The control sample size is very small. Please provide a clear explanation of the sample size selection and its statistical significance.

c. The results and table legends are unclear. Please describe the table legends clearly mostly about the Mann-Whitney and Fisher’s tests.

d. Include an analysis of the variation between males and females among subjects with STEMI and NSTEMI.

e. The explanation of the results is very poor and needs improvement.

f. Show the variation in IL-22 using GraphPad Prism

Comments on the Quality of English Language

Moderate editing of English language required

Author Response

Overall, the information presented in this manuscript is useful and I approve its publication after some major updates. 

Major comments: I suggest that these comments be updated before publication.

1. Moderate improvement in English language usage is needed. We did
2. The control sample size is very small. Please provide a clear explanation of the sample size selection and its statistical significance. 3.1 Healhty volunteers to have the normal circulating IL22, so we were looking for people to define normal circulating IL22 (70 is more than studies published in this field). OK
3. The results and table legends are unclear. Please describe the table legends clearly mostly about the Mann-Whitney and Fisher’s tests. We did. OK
4. Include an analysis of the variation between males and females among subjects with STEMI and NSTEMI.. Only patients with STEMI who underwent primary percutaneous coronary intervention were included. OK
5. The explanation of the results is very poor and needs improvement. Of note that we did not find articles about patients who underwent primary percutaneous intervention and their circulating IL22 were measured as we did (early). OK

 

Reviewer 4 Report

Comments and Suggestions for Authors

The present study aimed to explore interleukin-22 levels in STEMI patients, yielding clinically significant findings. However, the following concerns should be meticulously addressed:

Abstract lines 20-21, Considering the advancements in patient management, this statement seems overly severe. I suggest rephrasing it for a more balanced perspective.

Abstract, The part before objectives should be noted as background. Additionally, the rationale behind the focus on interleukin 22 is unclear.

Abstract, How could authors investigate differences in IL-22 between STEMI patients and healthy controls considering culprit coronary artery, door to-balloon time (DBT), final angiographic result, CAD classification, and the presence of diabetes mellitus (DM)? The selection of healthy controls inherently excludes these characteristics in the control group.

Methods, Please provide the definition of STEMI which was used to enroll eligible patients.

Methods, Has the current study received approval from the hospital's relevant ethics committee?

Methods, How were healthy controls identified? When were blood samples collected?

Serum IL-22 analysis, Please provide more detailed information on the methods used for analyzing IL-22.

Analysis, Lines 137-138, The authors' meaning is unclear when they state, "These subgroups were distributed by sex, age, clinical status, and angiographic profile." Could you provide clarification?

Table 1, The design of the table is unconventional and sparse, with a limited amount of information presented. I suggest reformatting the table and including the baseline characteristics of the control group for better clarity and comprehensiveness.

Discussion, The authors should provide further elaboration on their findings. Specifically, why did patients with a door-to-balloon time (DBT) of less than 60 minutes and those with the right coronary artery (RCA) as the culprit artery exhibit lower IL-22 levels? Additionally, why did CAD classification, angiographic success, and the presence of diabetes mellitus (DM) not influence serum IL-22 levels?

Author Response

Methods, Please provide the definition of STEMI which was used to enroll eligible patients.

STEMI definition: symptoms + ST elevation or new LBBB or new RBBB. OK

 

Methods, Has the current study received approval from the hospital's relevant ethics committee?

This study was conducted according to ethical principles for clinical research and was approved by ethical committee of the institution. OK

 

Methods, How were healthy controls identified? When were blood samples collected?

Healthy controls were identified based on their information that they do not have any disease. OK

Serum IL-22 analysis, Please provide more detailed information on the methods used for

analyzing IL-22. We did

 

Analysis, Lines 137-138, The authors' meaning is unclear when they state, "These subgroups were distributed by sex, age, clinical status, and angiographic profile." Could you provide clarification? Done

 

Table 1, The design of the table is unconventional and sparse, with a limited amount of information presented. I suggest reformatting the table and including the baseline characteristics of the control group for better clarity and comprehensiveness. We did. Ok

Discussion, The authors should provide further elaboration on their findings. Specifically, why did patients with a door-to-balloon time (DBT) of less than 60 minutes and those with the right coronary artery (RCA) as the culprit artery exhibit lower IL-22 levels? Additionally, why did CAD classification, angiographic success, and the presence of diabetes mellitus (DM) not influence serum IL-22 levels? DBT less than 60 minutes may be associated with less necrosis and culprit RCA also. So, less necrosis may be associated with lower circulating IL22. OK

 

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The authors have corrected the manuscript and answered my questions. However, I am not entirely satisfied with the authors' answers.

1. In response to the first question, the authors indicated the age of the control group, but nowhere in the article is the age of the patients mentioned, so it is still impossible to judge the comparability of the groups.

2. Previous experimental and clinical articles have shown an increase in IL-22 levels and suggested that this biomarker has a cardioprotective effect. It has been suggested that endogenous IL-22 plays an important role in preventing cardiac rupture after myocardial infarction, possibly by regulating inflammation and extracellular matrix metabolism. I would like to understand how reperfusion with PCI affects this relationship. I think the authors should put forward a hypothesis regarding this fact.

3. The authors still did not answer the question of how to interpret the lower IL-22 values ​​in the culprit artery subgroups RCA and LAD compared to LCX? This issue is not discussed in the text of the manuscript. Also, the text does not provide data on intergroup differences between these three subgroups. In addition, the authors note in the conclusion that "Within the subgroups, patients .... with the right coronary artery (RCA) as the culprit artery exhibited lower IL-22 levels" (lines 285-287). Why do the authors not mention the LAD subgroup, where IL-22 values ​​are also minimal?

4. Additional question - most biomarkers in acute myocardial infarction are associated with the size of myocardial necrosis. What was the troponin level in the subgroups? Was there an association of IL-22 levels with the troponin level?

Comments on the Quality of English Language

No comments

Author Response

1. In response to the first question, the authors indicated the age of the control group, but nowhere in the article is the age of the patients mentioned, so it is still impossible to judge the comparability of the groups.

 

Patients age:

We added.  (63.5 ± 11.6)

 

2. Previous experimental and clinical articles have shown an increase in IL-22 levels and suggested that this biomarker has a cardioprotective effect. It has been suggested that endogenous IL-22 plays an important role in preventing cardiac rupture after myocardial infarction, possibly by regulating inflammation and extracellular matrix metabolism. I would like to understand how reperfusion with PCI affects this relationship. I think the authors should put forward a hypothesis regarding this fact.

 

Added to text:

 

IL-22 plays an important role in preventing cardiac rupture after myocardial infarction based on experimental research and sometimes there are direfent results when we do it in humanbeing.

Reperfusion may reduce the amount of ischemia and necrosis, so it is possible that the way of inflammation be different. It is well defined that reperfusion changes the size of infarction. Besides, there is no information about the IL22 in patients with STEMI undergoing reperfusion through pecutaneuos coronary intervention. Other possibility is that the time of blood sample was too early to identify the peak of the IL22. These questions should be clarify in the future with other studies.

 

3. The authors still did not answer the question of how to interpret the lower IL-22 values ​​in the culprit artery subgroups RCA and LAD compared to LCX? This issue is not discussed in the text of the manuscript.

 

Added to text:

 

Myocardial infarction related to RCA was considered for long time less severe than left coronary artery infarction. Compared to left coronary artery tha RCA  supplies less amount of muscle.

We should understand that this information about RCA and IL22 is new, so it will be necessary more data to define this issue. Besides, this it is a subgroup analysis, so it is hypothesis generation result.

We know that sometimes we do not understand very well what happens, but the knowledge  should be built adding research on top of previous research.

Our team is looking for new information and we have a pipeline the be developed.

 

Also, the text does not provide data on intergroup differences between these three subgroups.

Added to text:

 

 In addition, the authors note in the conclusion that "Within the subgroups, patients .... with the right coronary artery (RCA) as the culprit artery exhibited lower IL-22 levels" (lines 285-287). Why do the authors not mention the LAD subgroup, where IL-22 values ​​are also minimal?

This is a comparison between three variables and we show the variable with lower level.

 

4. Additional question - most biomarkers in acute myocardial infarction are associated with the size of myocardial necrosis.

What was the troponin level in the subgroups?

Added to text:

We did not study this, but we added as a limitation.

Was there an association of IL-22 levels with the troponin level?

Added to text:

We did not study this, but we added as a limitation.

Reviewer 3 Report

Comments and Suggestions for Authors

The authors modified the manuscript.

Author Response

Comments and Suggestions for Authors

The authors modified the manuscript.

 

Thank you.

Reviewer 4 Report

Comments and Suggestions for Authors

The authors should clearly define the timing of blood sample collection relative to the index event.

Line 142: The sentence remains unchanged. No amendments were made.

Table 1, Despite the authors' reply indicating that some changes were incorporated, the table remains identical to that of the original submission.

The revision appears to be superficial, consisting mainly of single-word responses. My concerns have not been adequately addressed.

Comments on the Quality of English Language

Minor revisions are necessary

Author Response

Line 142: The sentence remains unchanged. No amendments were made.

Which sentence.

We did not find.

I am sorry, if possible clarify the question.

 

he authors should clearly define the timing of blood sample collection relative to the index event.

We added to text:

As all patients underwent PPCI and the timing of blood sample collection was within 12 hours after  index event

 

Table 1, Despite the authors' reply indicating that some changes were incorporated, the table remains identical to that of the original submission.

We have changed

 

The revision appears to be superficial, consisting mainly of single-word responses. My concerns have not been adequately addressed.

 

Your first review:

 

Abstract lines 20-21, Considering the advancements in patient management, this statement seems overly severe. I suggest rephrasing it for a more balanced perspective.

Changed:

Acute coronary syndrome (ACS) represents the most severe an important clinical manifestation of coronary artery disease (CAD)

Abstract, The part before objectives should be noted as background. Additionally, the rationale behind the focus on interleukin 22 is unclear.

We added:

Interleukin-22 (IL-22) regulates immune and inflammatory responses. This interleukin has been described in the scenario of the CAD, but there are no data in patients with STEMI undergoing PPCI

Abstract, How could authors investigate differences in IL-22 between STEMI patients and healthy controls considering culprit coronary artery, door to-balloon time (DBT), final angiographic result, CAD classification, and the presence of diabetes mellitus (DM)? The selection of healthy controls inherently excludes these characteristics in the control group.

These comparisons (culprit coronary artery, door to-balloon time (DBT), final angiographic result, CAD classification, and the presence of diabetes mellitus (DM) were between patients because as you said healthy controls

 

Methods, Please provide the definition of STEMI which was used to enroll eligible patients.

We define as describe below and added to text:

STEMI definition: symptoms + ST elevation or new LBBB or new RBBB.

 

Methods, Has the current study received approval from the hospital's relevant ethics committee?

Yes, as we described below and added to text:

This study was conducted according to ethical principles for clinical research and was approved by ethical committee of the institution.

 

Methods, How were healthy controls identified? When were blood samples collected?

We described below and added to text:

Healthy controls were identified based on their information that they do not have any disease.

Serum IL-22 analysis, Please provide more detailed information on the methods used for analyzing IL-22.

We described:

Timing of blood sample

Puncture technique

How to storage

Analyzing according to ELIZA

 

Analysis, Lines 137-138, The authors' meaning is unclear when they state, "These subgroups were distributed by sex, age, clinical status, and angiographic profile." Could you provide clarification?

We fixed.

We explained that these subgroups were compared.

 

Table 1, The design of the table is unconventional and sparse, with a limited amount of information presented. I suggest reformatting the table and including the baseline characteristics of the control group for better clarity and comprehensiveness.

We changed tables 1 and 3.

Controls are healthy, ie they do not have comorbidities. We change the results because  some tables we removed and show as text.

Discussion, The authors should provide further elaboration on their findings. Specifically, why did patients with a door-to-balloon time (DBT) of less than 60 minutes and those with the right coronary artery (RCA) as the culprit artery exhibit lower IL-22 levels?

Added to text:

Myocardial infarction related to RCA was considered for long time less severe than left coronary artery infarction. Compared to left coronary artery tha RCA  supplies less amount of muscle.

We should understand that this information about RCA and IL22 is new, so it will be necessary more data to define this issue. Besides, this it is a subgroup analysis, so it is hypothesis generation result.

We know that sometimes we do not understand very well what happens, but the knowledge  should be built adding research on top of previous research.

Our team is looking for new information and we have a pipeline the be developed.

.

DBT less than 60 minutes is associated with less necrosis and may be with different pattern of inflammation.

Reperfusion may reduce the amount of ischemia and necrosis, so it is possible that the way of inflammation be different. It is well defined that reperfusion changes the size of infarction. Besides, there is no information about the IL22 in patients with STEMI undergoing reperfusion through pecutaneuos coronary intervention. Other possibility is that the time of blood sample was too early to identify the peak of the IL22. These questions should be clarify in the future with other studies.

 

 

Additionally, why did CAD classification, angiographic success, and the presence of diabetes mellitus (DM) not influence serum IL-22 levels?

Our study show that CAD classification, angiographic success, and the presence of diabetes mellitus (DM) did not influence serum IL-22 levels.  This is the first study to evaluate these issues in the described population. The absence of differences between these subgroups should be better understand and additional studies are needed to clarify these results.

Round 3

Reviewer 2 Report

Comments and Suggestions for Authors

The authors responded to my additional questions and comments, and made additional corrections to the text of the manuscript. I am still not entirely satisfied with these answers, but I leave the final decision to the editor.

Comments on the Quality of English Language

No comments

Reviewer 4 Report

Comments and Suggestions for Authors

I would like to thank the authors for appropriately revising their manuscript.