Temporal change of lymphocyte subunits for maladaptive remodeling after anterior myocardial infarction

Abstract

Objectives

Lymphocytes are key players in the adaptive immune system, playing an important role in the anti-inflammatory balance in the post-myocardial infarction (MI) period and being involved in healing process. We aimed to investigate temporal changes in lymphocyte subunits in maladaptive remodeling following acute myocardial infarction.

Design and setting

A total of 84 patients with anterior ST-segment elevation MI (STEMI) were enrolled. Lymphocyte subunits were measured 1 day, 2 and 6 weeks after MI. Maladaptive cardiac remodeling was defined as an increase in left ventricular end-diastolic volume by ≥12% in cardiac magnetic resonance imaging at the 6-months follow-up.

Participants

A total of 84 patients with anterior STEMI were enrolled.

Measurements and results

On the first day post-MI, the median number of total lymphocytes, T cells, and B cells were higher in the maladaptive remodeling group than in the without maladaptive remodeling group. Two weeks post-MI, the median number of B cells was higher in the maladaptive remodeling group, but similar at 6 weeks post-MI. Regression analysis revealed that a high number of B cells on the first day post-MI was related to maladaptive remodeling.

Conclusions

In the maladaptive remodeling group, both inflammation markers, T and B lymphocyte levels were higher in the initial phase of MI, while B cells were approximately two-fold higher and an independent predictor of maladaptive remodeling. This study strongly supports the idea of developing immunotherapies or treatments that target B cells in cardiac remodeling.

Keywords

Cardiac remodeling flow cytometry lymphocytes myocardial infarction inflammation

Introduction

Immune cells have been shown to mediate both protective and detrimental effects on cardiac remodeling.¹ This uncertainty surrounding the immune system's role and inconsistent results of recent clinical trials question the benefits of anti-inflammatory therapies during acute myocardial infarction (MI).¹ An excessive inflammatory response can determine the outcome of cardiac repair and cause a maladaptive change in the structure and function of the heart.² Lymphocytes are key players in the adaptive immune system, playing an important role in the anti-inflammatory balance in the post-MI period.³

It has been shown that T cells participate in myocardial inflammation and the healing process, and regulatory T cells mediate regenerative programs.^4,5 Sustained responses of T cells after MI may lead to maladaptive remodeling and contribute to heart failure in the future.⁶ CD3 cells represent total T lymphocytes,⁷ and anti-CD3 antibody treatment has been shown to reduce scar formation in a rat MI model.⁸ Therefore, reparative processes in the myocardium after MI may require temporal regulation in biphasic immune cells.⁹ B lymphocytes can influence the myocardial mass and pro-inflammatory response by playing a role in the production of natural antibodies.¹⁰

Evaluation of the temporal changes in lymphocyte subunits can provide more detailed information about the mechanism of maladaptive remodeling and make the new paradigms of cardiac vulnerability easier to understand and apply. Moreover, temporal change can be a guide for when lymphocyte therapeutic targets should be applied after MI. In the present study, we investigated temporal changes in lymphocyte subunits in maladaptive remodeling following MI.

Materials and methods

Study population and design

This multicenter prospective study was performed from June 2015 through June 2018 and was designed in accordance with the Declaration of Helsinki revised in Brazil in 2013 and Good Clinical Practice Guidelines. Approval was obtained from the local ethics committee commission (Decision Date/No.: 24.06.2013/106), and all patients who participated in the study filled in informed consent forms. Patient recruitment and data collection for this study was done from June 2015 through June 2018. Assuming an alpha of 0.05, a power of 0.80, and with 20% estimated maladaptive remodeling rate in line with previous reports,¹¹ the estimated sample size was at least 40 patients in total.

Five hundred sixty-seven patients (>18 years of age) who presented to the emergency department with first ST-segment elevation MI (STEMI) (by the third universal definition of MI)¹² and who underwent primary percutaneous coronary intervention (PCI) within the first 12 h of chest pain were evaluated in the study. All STEMI patients were managed according to the latest guidelines of the European Society of Cardiology.¹³ Nearly 480 acute MI patients were evaluated, many of whom met the exclusion criteria, some did not want to participate in the study. Patients diagnosed with acute anterior MI but 25 with different rheumatological diseases, 20 patients with acute infections, and 30 patients receiving various cancer treatments were excluded from the study. Twenty patients were lost in follow-up, and thus, the remaining 84 first anterior STEMI patients were included and data of these patients were evaluated in the study.

The patients who met the following criteria were excluded from the study: late admission, over 75 years old, failed PCI, claustrophobia, in cardiogenic shock or need of intra-aortic balloon pump, the history of silent ischemia/infarct and the history of prior PCI, right coronary artery occlusion, any kind of systemic inflammatory disease, autoimmune disease, the history of use of chronic corticosteroid or anti-inflammatory drugs, malignancy, pregnancy or delivery within the last 90 days or breastfeeding mothers, and planned emergency or elective coronary artery by-pass graft after angiography. Since right coronary artery sends blood to the right side of the heart and the definition of maladaptive remodeling was based on an increase in left ventricular end-diastolic volume (LVEDV) of ≥12% at 6 months post-MI,^11,14 patients with acute inferior MI or MI with right coronary artery occlusion were excluded from the study.

The clinical, demographic, laboratory, and radiological findings were timely recorded in the patient files during the follow-up. The Global Registry of Acute Cardiac Events Risk (GRACE) score was obtained using the official calculator. Blood samples were taken early in the day to prevent the effect of daily rhythm differences in the expression of inflammatory markers. The same laboratory technician performed the tests after the collection of all samples and ran them in the same laboratory in a single session with the same device.

Biochemical parameters

Blood samples were obtained from the antecubital vein at presentation for troponin and lipid panel, and 1 day, 2 weeks (14 days), and 6 weeks (45 days) after admission for lymphocyte subunits. The samples were centrifuged at 1500 r/min for 10 min and then stored at −80 °C. Complete blood cell counts were obtained with a Sysmex XN-1000 hematology analyzer (Sysmex Corporation, Kobe, Japan). Biochemical parameters were measured with an Automatic Biochemical Analyzer 7600-120 (Hitachi High Technologies, Tokyo, Japan). Lipid parameters were determined by the homogeneous enzymatic colorimetric method with a Hitachi Modular P800 autoanalyzer (Roche Diagnostics Corp., New York, USA). Friedewald's method was employed to calculate the low-density lipoprotein.¹⁵

Flow cytometric analysis

A FACSAria III (Becton Dickinson Bioscience, San Jose, CA, USA) was used for flow cytometry acquisition and analyses were performed with FACS^® Diva software, and 50,000 events were collected per sample. For cytofluorometry, the following antibodies were used: BD Horizon™ V500 labeled antibodies to CD3 (catalog no. 561416) and phycoerythrin (PE-Cy™ 7)-labeled antibodies to CD19 (catalog no. 557835). Nonspecific immunoglobulin G isotypes were used as negative controls. For red blood cell lysis, 2 mL of lysing buffer was added to the blood sample tube (BD FACS™ lysing solution 100 mL; catalog no. 349202). Exemplary flow cytometric findings are shown in Figure 1.

Figure 1.

Change of lymphocytes subpopulations after myocardial infarction.

Cardiac magnetic resonance imaging

After inclusion, follow-up 3-T scanner cardiac magnetic resonance (CMR) imaging (Magnetom Skyra, Siemens Medical Systems, Erlangen, Germany) was performed 2 weeks and 6 months after the index event. Acquisition of one four-chamber view, cine short-axis sections, and one two-chamber view were included in the CMR imaging protocol. The indices of left ventricular (LV) systolic function were evaluated with a retrospective electrocardiogram-gated turbo-fast low angle shot sequence. The imaging parameters were as follows: echo time 1.42 ms, repetition time 39 ms, flip angle 57°, voxel size 1.67 × 1.67 × 6 mm³. The readers measured LVEDV and LV end-systolic volume (LVESV) with Siemens syngo.via VA30. The end-diastolic phase was selected as the first phase of the cine images. This phase was determined by visually identifying the end of inward motion of the left ventricle.¹⁴ LV stroke volume was calculated as LVEDV minus LVESV, and ejection fraction (EF) was calculated as follows: EF = [(LVEDV − LVESV)/LVEDV] × 100.

The definition of maladaptive remodeling was based on an increase in LVEDV of ≥12% at 6 months post-MI.^11,14

Statistical analysis

Statistical analysis was performed using SPSS 20 for Windows (IBM Corp., Armonk, NY, USA). The normal distribution of data was evaluated by a Shapiro–Wilk test. Numeric variables with and without normal distribution were plotted as mean ± standard deviation and median (25th and 75th interquartile range), respectively. The categorical variables were indicated as numeric and percentile values. Student's t-test or the Mann–Whitney U test was used for comparison of numeric variables between the two groups according to the distribution of normality. The chi-square test, Yates’ correction, and Fischer's exact test were used for comparison of the categorical data. Mixed model for repeated-measures analysis was performed for the comparison of cytokine levels in the post-MI period and during follow-up according to the remodeling groups. Logistic regression analysis was used to identify the independent predictors of maladaptive remodeling. Values of p < 0.05 (*) were considered to be significant. The changes in CMR imaging parameters and lymphocyte levels in the post-MI period are shown by “Δ.”

Results

Detailed demographic, laboratory, and clinical findings at the time of admission of the study population are shown in Table 1. The study population consisted of 11 women and 73 men. Maladaptive remodeling was detected in 21 patients (25%) at the end of 6 months. Mean cardiac troponin I (cTn-I) levels, mean monocyte levels, and median C-reactive protein (CRP) levels were higher in the maladaptive remodeling group than in the without maladaptive remodeling group. There were no significant differences in the other baseline findings between the with and without maladaptive remodeling groups.

Table 1.

Demographic, laboratory, and clinical findings of the study population.

Variables	Allpopulationn = 84	Maladaptive remodeling		p
Variables	Allpopulationn = 84	Yesn = 21	Non = 63	p
Gender, n (%)
Female	11 (13.1)	4 (19.0)	7 (11.1)	0.575
Male	73 (86.9)	17 (81.0)	56 (88.9)	0.575
Age, years	54.4 ± 7.8	55.3 ± 8.3	54.1 ± 7.7	0.555
BMI, kg/m²	27.1 ± 4.2	25.8 ± 5.2	27.6 ± 3.9	0.46
Smoking, n (%)	44 (52.4)	11 (52.4)	33 (52.4)	0.999
Hypertension, n (%)	32 (38.1)	7 (33.3)	25 (39.7)	0.796
Diabetes mellitus, n (%)	19 (22.6)	3 (14.3)	16 (25.4)	0.452
SBP, mm Hg	123.6 ± 17.9	127.6 ± 20.0	122.5 ± 16.2	0.243
DBP, mm Hg	77.0 ± 11.0	80.9 ± 10.4	75.9 ± 11.1	0.125
HR, beat per min	77.5 ± 18.5	76.7 ± 15.1	77.8 ± 19.6	0.805
Door-to-balloon time, min	41.3 ± 8.9	37.8 ± 9.6	42.6 ± 8.7	0.321
Symptom-to-balloon time, min	290.6 ± 51.4	312.4 ± 46.2	281.6 ± 52.6	0.274
GRACE score	124.4 ± 31.4	133.7 ± 30	121.3 ± 31.5	0.118
Pre-PCI TIMI flow, n (%)
0	54 (64.3)	13 (61.9)	41 (65.1)	0.902
1	10 (11.9)	2 (9.5)	8 (12.7)
2	9 (10.7)	3 (14.3)	6 (9.5)
3	11 (13.1)	3 (14.3)	8 (12.7)
Post-PCI TIMI flow >2, n (%)	81 (96.4)	21 (100.0)	60 (95.2)	0.734
cTn-I, ng/L	43.4 ± 15.0	49.7 ± 15.3	41.3 ± 14.6	0.027*
Glucose, mg/dL	115 (96–153)	115.5 (93.5–164.5)	115 (96–153)	0.885
Hemoglobin, g/dL	14.0 ± 1.5	13.9 ± 1.4	14.1 ± 1.6	0.800
WBC, ×10³/mm³	12.2 ± 3.7	11.4 ± 3.9	12.4 ± 3.7	0.282
Neutrophils, ×10³/mm³	7.5 ± 2.0	7.8 ± 1.9	7.3 ± 2.1	0.337
Platelets, ×10³/mm³	267.5 ± 68.4	285.9 ± 60.2	254.7 ± 69.6	0.070
Monocyte, ×10³/mm³	0.8 ± 0.2	0.8 ± 0.2	0.7 ± 0.2	0.040*
Total cholesterol, mg/dL	204.4 ± 46.0	202.0 ± 47.7	205.2 ± 45.7	0.787
HDL, mg/dL	41.5 ± 10.1	44.8 ± 10.8	40.4 ± 9.7	0.086
LDL, mg/dL	138.6 ± 40.3	133.3 ± 46.8	140.4 ± 38.1	0.492
Triglycerides, mg/dL	160 (106–201)	162 (127–258)	150 (95.5–201)	0.272
Creatinine, mg/dL	1.0 ± 0.2	1.0 ± 0.2	1.0 ± 0.2	0.656
CRP, mg/L	19.1 (9.9–27.6)	22.8 (11–32)	14.2 (8–21)	0.035*
Discharge therapy, n (%)
ACE/ARB	81 (96.4)	20 (95.2)	61 (96.8)	0.999
Beta blockers	82 (97.6)	20 (95.2)	62 (98.4)	0.999
Statins	82 (97.6)	21 (100.0)	61 (96.8)	0.999

ACE: angiotensin-converting enzyme; ARB: angiotensin II receptor blocker; BMI: body mass index; cTn-I: cardiac troponin I; CRP: C-reactive protein; DBP: diastolic blood pressure; GRACE: Global Registry of Acute Cardiac Events Risk; HDL: high-density lipoprotein; HR: heart rate; IQR: interquartile range; LDL: low-density lipoprotein; PCI: percutaneous coronary intervention; SBP: systolic blood pressure; TIMI: thrombolysis in myocardial infarction; WBC: white blood cell count.

Data are mean ± standard deviation, median (IQR), or number (%).

*p < 0.05 shows statistical significance.

Of the 84 patients who underwent primary PCI, 13 had also concurrent atrial fibrillation. Of these 13 patients, 5 were receiving rivaroxaban, 5 were receiving dabigatran, and 3 were receiving apixaban. Of the 84 patients included in the study, 60% were taking ticagrelor, 30% were taking clopidogrel, and 10% were taking prasugrel. None of these patients had bleeding complication during follow-up period. This was consistent with the Polish Atrial Fibrillation Registry results.¹⁶

Eighty percent of the procedures were performed using the femoral approach, while the remaining 20% were performed via the radial approach. All procedures were performed by experienced specialists. Therefore, the importance of operator experience in the success of these procedures was not investigated. Eighty percent of the procedures were performed during working hours, and 20% were performed during night shifts. Only one radiologist evaluated the magnetic resonance imaging blindly three times at different times and the intra-observer variability coefficient was found to be r = 0.91.

Of the approximately 480 acute MI patients evaluated in this study, 50 were excluded because they were in acute cardiogenic shock. This result was consistent with the literature. Eighty percent of the interventions were performed via the femoral route.¹⁷

Despite symptom-to-balloon time is not significant, there are numerical differences, our low sample size might be not sufficient to detect differences.

CMR imaging findings of the with and without maladaptive remodeling groups did not show significant differences at 2 weeks post-MI. Six months post-MI, mean left ventricular ejection fraction was lower and median LVEDV and median LVESV were higher in the maladaptive remodeling group than in the without maladaptive remodeling group. Six months post-MI, there was a significant worsening of LV volume and functions in the maladaptive remodeling group compared to the without maladaptive remodeling group (Table 2).

Table 2.

Results of cardiac magnetic resonance imaging.

Variables	2 weeks post-MI			6 months post-MI
	Maladaptive remodeling		p	Maladaptive remodeling		p	Δp
	Yes	No		Yes	No
	n = 21	n = 63		n = 21	n = 63
LVEF, %	49.0 ± 10.1	50.0 ± 8.8	0.832	44.6 ± 9.4	52.8 ± 9.2	<0.001	<0.001*
LVEDV, mL	158 (128–180)	144 (124–165)	0.213	184 (145–210)	135 (112–160)	0.004	<0.001*
LVESV, mL	78 (54–111)	69 (57–95)	0.446	97 (66–124)	63 (52–85)	0.006	<0.001*
Stroke volume, mL	70.5 ± 12.9	69.4 ± 16.3	0.759	74.3 ± 15.7	71.5 ± 16.0	0.830	0.078
CO, mL/min	4.9 ± 1.0	4.9 ± 1.1	0.941	4.7 ± 1.2	5.0 ± 1.2	0.925	0.085
Infarct size, % of LV	22 (12–26)	18 (14–20)	0.023	19 (10–23)	15 (11–19)	0.045	0.456

CO: cardiac output; IQR: interquartile range; LV: left ventricular; LVEDV: left ventricular end-diastolic volume; LVEF: left ventricular ejection fraction; LVESV: left ventricular end-systolic volume; MI: myocardial infarction.

Data are mean ± standard deviation or median (IQR).

*p < 0.05 shows statistical significance.

Although data for this study were collected between 2015 and 2018, drug-eluting stent ) was used in 80% of the patients, bare metal stent was used in the remaining 20%, and no bioabsorbable vascular stent was used. Therefore, our results are not consistent with the 2014–2015 ORPKI Polish National Registry results.¹⁸

On the first day post-MI, the median number of total lymphocytes, median number of T cells, and median number of B cells were higher in the maladaptive remodeling group than in the without maladaptive remodeling group. At 2 weeks post-MI, the median number of B cells was higher in the maladaptive remodeling group than in the without maladaptive remodeling group, while T cells did not significantly differ (Table 4). At 6 weeks post-MI, lymphocyte subunits were similar between the with and without maladaptive remodeling groups (Figure 1) (Table 3).

Table 3.

Subunits of lymphocytes among with and without maladaptive remodeling groups after myocardial infarction.

6 weeks post-MI	Without maladaptive remodeling group	With maladaptive remodeling group	p
Total lymphocytes	9968 (7931.5– 11,983.5)	10,550 (9368– 12,979)	0.150
T cells	6927.5 (5206–8687.5)	7852 (5503–9079)	0.198
T cells, %	69 ± 7.5	69.2 ± 6.7	0.934
B cells	808 (502–1214.5)	922 (515–1451)	0.178
B cells, %	8.5 (6–12.5)	9.7 (6.2–12.4)	0.502

IQR: interquartile range; MI: myocardial infarction.

Data are mean ± standard deviation or median (IQR).

p < 0.05 shows statistical significance.

The number of B cells was lower at 2 weeks compared to the first day post-MI in the maladaptive remodeling group, while it was similar at 6 weeks compared to 2 weeks post-MI. In the without maladaptive remodeling group, the number of B cells was similar between the first day and 2 weeks post-MI, while it was higher 6 weeks post-MI (Table 4).

Table 4.

Change of lymphocyte subunits after myocardial infarction in with and without maladaptive remodeling groups.

Lymphocytes	Maladaptive remodeling	First day post-MI	2 weeks post-MI	6 weeks post-MI	p _time	Δp1	Δp2	Δp3
Total lymphocytes	Yes, n = 27	9107 (7266– 10,855)	9119 (6817– 11,887)	10,550 (9368– 12,979)	0.047*	0.041*	0.022*	0.078
Total lymphocytes	No, n = 57	6157 (4902–7829)	7705 (6268–9951)	9245 (7806– 11,864)	<0.001*	0.041*	0.022*	0.078
T cells	Yes, n = 27	5937 (4983–7349)	6326 (4506–8366)	7852 (5503–9079)	0.044*	0.045*	0.040*	0.764
T cells	No, n = 57	4159 (3195–5280)	5423 (4362–6314)	6611 (5146–8626)	<0.001*	0.045*	0.040*	0.764
T cells, %	Yes, n = 27	65.8 ± 5.2	66.8 ± 8.5	69.2 ± 6.7	0.304	0.887	0.734	0.827
T cells, %	No, n = 57	66.4 ± 10.9	67.1 ± 8.7	68.9 ± 7.8	0.156	0.887	0.734	0.827
B cells	Yes, n = 27	1236 (959–1872)	960 (652–1645)	922 (515–1451)	0.042*	0.030*	0.009*	0.014*
B cells	No, n = 57	622 (432–929)	636 (489–910)	802 (494–1176)	0.049*	0.030*	0.009*	0.014*
B cells, %	Yes, n = 27	13.5 (11.4–17.2)	12.4 (9.4–14.3)	9.7 (6.2–12.4)	<0.001*	0.955	0.068	0.082
B cells, %	No, n = 57	10.8 (8.4–13.9)	8.5 (6.2–10.7)	8.5 (5.9–12.6)	<0.001*	0.955	0.068	0.082

p_time: first day vs. 2 weeks vs. 6 weeks in remodeling groups; Δp1: comparison of the changes between first day and 2 weeks post-MI in the remodeling groups (with vs. without maladaptive remodeling); Δp2: comparison of the changes between first day and 6 weeks post-MI in the remodeling groups (with vs. without maladaptive remodeling); Δp3: comparison of the changes between 2 and 6 weeks post-MI in the remodeling groups (with vs. without maladaptive remodeling); IQR: interquartile range; MI: myocardial infarction.

Data are mean ± standard deviation or median (IQR).

*p < 0.05 shows statistical significance.

Multivariable regression analysis including cTn-I, CRP, infarct size, and total lymphocyte count on the first day post-MI (model I) revealed infarct size and total lymphocyte count to be independent predictors of maladaptive remodeling. According to this analysis, an increase of 1000 cells in the total lymphocyte would increase the odds of maladaptive remodeling by 2.27-fold (odds ratio (OR) = 2.27, p < 0.001). In addition, the regression model in which lymphocyte subunits (model II) were included showed that a 100-cell increase in B lymphocytes increased the odds of lymphocytes by 1.29-fold (OR = 1.29, p < 0.001). Moreover, model II exhibited a higher goodness of fit compared to model I (model I: Nagelkerke R²: 0.40 vs. model II: Nagelkerke R²: 0.47) (Table 5).

Table 5.

Independent predictor of maladaptive remodeling.

	Variables	Univariable				Multivariable
		OR	95% CI	p	OR	95% CI	p
		OR	Lower–upper	p	OR	Lower–upper	p
Model I	cTn-I	1.07	1.01–1.12	0.035*	—	—	—
	CRP	1.06	1.03–1.10	0.041*	—	—	—
	Infarct size	1.03	1.01–1.05	0.026*	1.04	1.01–1.08	0.047*
	Monocyte	1.03	1.01–1.06	0.045*	—	—	—
	Total lymphocyte	1.88	1.38–2.56	<0.001*	2.27	1.49–3.47	<0.001*
					Nagelkerke R² = 0.402; p < 0.001*
Model II	cTn-I	1.07	1.01–1.12	0.035*
	CRP	1.06	1.03–1.10	0.041*
	Infarct size	1.03	1.01–1.05	0.026*	1.05	1.01–1.09	0.045*
	Monocyte	1.03	1.01–1.06	0.045*
	T cells	2.29	1.50–3.49	<0.001*
	B cells	1.30	1.14–1.48	<0.001*	1.29	1.14–1.48	<0.001*
					Nagelkerke R² = 0.471; p < 0.001*

cTn-I: cardiac troponin I; CRP: C-reactive protein; CI: confidence interval; LVEF: left ventricular ejection fraction; OR: odds ratio.

Reference group: without maladaptive remodeling. Total lymphocyte and T cells values are divided by 1000, and B cells are divided by 100. All analysis adjusted for LVEF and cardiac output.

*p < 0.05 shows statistical significance.

Discussion

The results of the present study both support and extend previous studies suggesting that T and B lymphocytes play an important role in modulating cardiac remodeling following MI. In our study, on the first day post-MI, T and B lymphocyte levels were higher in the maladaptive remodeling group. At 2 weeks post-MI, T lymphocyte levels did not differ between the groups, while B lymphocyte levels were higher in the maladaptive remodeling group. At 6 weeks post-MI, T and B lymphocyte levels were similar between the groups. Multivariable regression analysis revealed that an increase in B lymphocytes on the first day post-MI was related to increased odds of maladaptive remodeling. The temporal change in T and B lymphocytes may be guiding for human studies, consistent with the therapeutic targets demonstrated in experimental studies.

The inflammatory response following acute MI triggers a complex activation of molecular, cellular, and physiological events.¹⁹ In the subacute phase of MI, inflammatory cells migrate to the damaged area to remove necrotic tissue and promote scar formation. On the other hand, lymphocyte response may regulate the transition of inflammation from the acute to chronic phase.²⁰ This follows a healing process initiated by the immune system that causes pathological and structural changes in the heart.²¹ High CRP and cTn-I levels reflect a higher inflammatory response. Lymphocytes play a role in the immune response to inflammation and are involved in the healing process by inducing pro- and anti-inflammatory cytokines.^22,23 Evaluation of changes in serial measurements of myocardial immune cell accumulations post-MI by cell-specific transcriptome or proteome analyses may be instrumental in elucidating the mechanisms of inflammation after cardiac tissue injury, including cytokine storms.

To date, most of the data on lymphocyte subsets have been based on mouse MI models, and B and T lymphocyte levels have been reported to increase 5- to 10-fold after MI and peak at 7 days.²⁴ The current findings show that T lymphocytes reach peak levels 6 weeks post-MI in patients with and without maladaptive remodeling, while B lymphocytes reach peak levels on the first day post-MI in patients with maladaptive remodeling. Reperfusion may affect leukocyte migration into the myocardium due to a reduction in infarct volume, thus causing an earlier peak of leukocytes, including lymphocytes.²⁵ T cells are activated as a result of the interaction of damage-associated molecular patterns released from damaged cardiac cells with B cells, and contribute to the pro-inflammatory environment.²⁶ This suggests that in an excessive inflammatory response the activation of T cells may increase due to B cell response. This may explain the higher T and B cells on the first day post-MI in patients with maladaptive remodeling. On the other hand, induced Treg cells developed by CD4+ T cells can suppress the functions of B cells and modulate the monocyte/macrophage interaction, thereby affecting cardiac healing.

In our previous study, we showed that interleukin (IL)-10, IL-19, and IL-26 expression were higher on the first day post-MI in patients who developed adverse remodeling, and we suggested that it might have been due to an excessive inflammatory response.²⁷ A disruption in T cell activation in the excessive inflammatory response may determine the outcome of cardiac remodeling post-MI, and may cause susceptibility to heart failure in the long term. Therefore, T lymphocytes may be a therapeutic target. Anti-CD3 antibody treatment in the rat model of acute MI resulted in reduced scar size, and cardio-protective and pro-angiogenetic pathways were not affected by the treatment. However, anti-CD3 antibody treatment caused qualitative changes in miRNA expression.⁸

Previous limited studies showed that MI can trigger infiltration of mature circulating B cells and an increase in myocardial CD19+ cell count post-MI and is reported to contribute to cardiac remodeling.^21,28 The proposed mechanism involves the infiltration of CD19 + IgD + IgMlo B lymphocytes into the infarcted myocardium and regulating of the migration of Ly6C+ monocytes from the bone marrow via CCL7.²⁸ On the other hand, Horckmans et al.²⁹ showed that the presence of minimal CD19+ cells in the myocardium post-MI suggests that CD19+ cells aggregate in lymphoid clusters in pericardial adipose tissue. They also found that B-cell depletion inhibited T-cell expansion in pericardial adipose tissue.²⁹ In an experimental study, Cordero-Reyes et al.³⁰ showed in the absence of B cells reduced hypertrophy, collagen deposition, and cytokine release and preserved LV function in a non-surgical mouse model of ischemic cardiomyopathy. Thus, they showed that maladaptive remodeling was attenuated by antibody-bound depletion of B cells.³⁰ These findings are consistent with lower B cells in the without maladaptive remodeling group. Activated B lymphocytes can increase monocyte migration and release of collagen-I, cytokines, and chemokines, which may adversely affect cardiac repair. However, there are limited studies evaluating the role of B lymphocytes in cardiac remodeling after MI and their mechanisms are still unclear. Therefore, more human and animal studies are required.

The main limitation of this study was that it did not include a detailed inflammatory panel. Due to the complex nature of inflammatory and immune responses, a detailed panel of biomarkers may be required for residual inflammatory risk assessment. In addition, evaluation of T and B lymphocyte subunits could better explain the effect of immune and adaptive immunity on cardiac remodeling. Finally, cytokines induced by T and B lymphocytes may have greater effects on cardiac remodeling.

Conclusion

The outcome of cardiac remodeling after STEMI depends on the innate and adaptive immune system involved in the inflammatory response. In the maladaptive remodeling group, both inflammation markers and T and B lymphocyte levels were higher in the initial phase of MI. The number of B cells at first day post-MI was approximately two-fold higher in those who developed maladaptive remodeling compared to those who did not, and they were identified as an independent predictor of maladaptive remodeling. Therefore, our study strongly supports the idea of developing immunotherapies or treatments that target B cells in cardiac remodeling.

Footnotes

ORCID iDs

Ferhat Eyyupkoca

Huseyin Oren

Ajar Kocak

Musa Baran Akbaba

Muhammed Emre Onder

Omer Faruk Ates

Ethical considerations

The study was performed in accordance with the Declaration of Helsinki, and approved by The Faculty of Medicine Non-Drug Clinical Research Ethics Committee of the Ankara Yildirim Beyazit University, on June 24, 2013, under Decision No. 2013/106.

Consent to participate

Written informed consent was obtained from all patients.

Consent for publication

Informed consent for publication was provided by the participant(s) or a legally authorized representative.

Author contributions

Concept – FE; design – FE; supervision – FE; materials – FE, HO, OY, AK, MBA, MEO, and OFA; data collection and/or processing – FE, HO, OY, AK, MBA, MEO, and OFA; analysis and/or interpretation – FE, HO, OY, AK, MBA, MEO, and OFA; literature search – FE, HO, OY, AK, MBA, MEO, and OFA; writing – FE and HO; critical review – FE and HO. All authors read and approved the final manuscript.

Funding

The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The authors declared that this research received financial support from the Ministry of Health of the Republic of Turkey (Department of Research, Development and Health Technology Evaluation) 2015/SAGEM-2/001 project.

Declaration of conflicting interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Data availability statement

The data that support the findings of this study are available on request from the corresponding author.

Guarantor

Ferhat Eyyupkoca is the guarantor for the work. The guarantor accepts full responsibility for the work and/or the conduct of the study, had access to the data, and controlled the decision to publish.

References

Kologrivova

Shtatolkina

Suslova

, et al. Cells of the immune system in cardiac remodeling: main players in resolution of inflammation and repair after myocardial infarction. Front Immunol 2021; 12: 664457.

Ong

Hernandez-Resendiz

Crespo-Avilan

, et al. Inflammation following acute myocardial infarction: multiple players, dynamic roles, and novel therapeutic opportunities. Pharmacol Ther 2018; 186: 73–87.

Santos-Zas

Lemarie

Tedgui

, et al. Adaptive immune responses contribute to post-ischemic cardiac remodeling. Front Cardiovasc Med 2018; 5: 198.

Hofmann

Beyersdorf

Weirather

, et al. Activation of CD4+ T lymphocytes improves wound healing and survival after experimental myocardial infarction in mice. Circulation 2012; 125: 1652–1663.

Ramos

Dalbo

Leite

, et al. The autoimmune nature of post-infarct myocardial healing: oral tolerance to cardiac antigens as a novel strategy to improve cardiac healing. Autoimmunity 2012; 45: 233–244.

Bansal

Ismahil

Goel

, et al. Activated T lymphocytes are essential drivers of pathological remodeling in ischemic heart failure. Circ Heart Fail 2017; 10: e003688.

Boag

Das

Shmeleva

, et al. T lymphocytes and fractalkine contribute to myocardial ischemia/reperfusion injury in patients. J Clin Invest 2015; 125: 3063–3076.

Wernly

Paar

Aigner

, et al. Anti-CD3 antibody treatment reduces scar formation in a rat model of myocardial infarction. Cells 2020; 9: 295.

Wagner

Khan

Mohsin

. Healing the broken heart; the immunomodulatory effects of stem cell therapy. Front Immunol 2020; 11: 639.

10.

Casarotti

ACA

Teixeira

Longo-Maugeri

, et al. Role of B lymphocytes in the infarcted mass in patients with acute myocardial infarction. Biosci Rep 2021; 41: BSR20203413.

11.

Bulluck

Carberry

Carrick

, et al. Redefining adverse and reverse left ventricular remodeling by cardiovascular magnetic resonance following ST-segment-elevation myocardial infarction and their implications on long-term prognosis. Circ Cardiovasc Imaging 2020; 13: e009937.

12.

Thygesen

Alpert

Jaffe

, et al. Third universal definition of myocardial infarction. J Am Coll Cardiol 2012; 60: 1581–1598.

13.

Ibanez

James

Agewall

, et al. 2017 ESC guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation: the task force for the management of acute myocardial infarction in patients presenting with ST-segment elevation of the European Society of Cardiology (ESC). Eur Heart J 2018; 39: 119–177.

14.

Bulluck

Crimi

, et al. Defining left ventricular remodeling following acute ST-segment elevation myocardial infarction using cardiovascular magnetic resonance. J Cardiovasc Magn Reson 2017; 19: 26.

15.

Friedewald

Levy

Fredrickson

. Estimation of the concentration of low-density lipoprotein cholesterol in plasma, without use of the preparative ultracentrifuge. Clin Chem 1972; 18: 499–502.

16.

Uziębło-Życzkowska

Krzesiński

Maciorowska

, et al. Antithrombotic therapy in patients with atrial fibrillation undergoing percutaneous coronary intervention, including compliance with current guidelines—data from the Polish Atrial Fibrillation (POL-AF) Registry. Cardiovasc Diagn Ther 2021; 11: 14–27.

17.

Tokarek

Dziewierz

Plens

, et al. Radial approach reduces mortality in patients with ST-segment elevation myocardial infarction and cardiogenic shock. Pol Arch Intern Med 2021; 131: 421–428.

18.

Rzeszutko

Tokarek

Siudak

, et al. Patient profile and periprocedural outcomes of bioresorbable vascular scaffold implantation in comparison with drug-eluting and bare-metal stent implantation. Experience from ORPKI Polish National Registry 2014–2015. Postepy Kardiol Interwencyjnej 2016; 12: 321–328.

19.

Naresh

Klibanov

, et al. Monocyte and/or macrophage infiltration of heart after myocardial infarction: MR imaging by using T1-shortening liposomes. Radiology 2012; 264: 428–435.

20.

Kino

Khan

Mohsin

. The regulatory role of T cell responses in cardiac remodeling following myocardial infarction. Int J Mol Sci 2020; 21: 5013.

21.

Westman

Lipinski

Luger

, et al. Inflammation as a driver of adverse left ventricular remodeling after acute myocardial infarction. J Am Coll Cardiol 2016; 67: 2050–2060.

22.

Khan

Ghazanfar

. T lymphocytes and autoimmunity. Int Rev Cell Mol Biol 2018; 341: 125–168.

23.

Chung

Lee

Choi

, et al. Blood neutrophil/lymphocyte ratio is associated with cerebral large-artery atherosclerosis but not with cerebral small-vessel disease. Front Neurol 2020; 11: 1022.

24.

Yan

Anzai

Katsumata

, et al. Temporal dynamics of cardiac immune cell accumulation following acute myocardial infarction. J Mol Cell Cardiol 2013; 62: 24–35.

25.

Hofmann

Frantz

. Role of lymphocytes in myocardial injury, healing, and remodeling after myocardial infarction. Circ Res 2015; 116: 354–367.

26.

Garcia-Rivas

Castillo

Gonzalez-Gil

, et al. The role of B cells in heart failure and implications for future immunomodulatory treatment strategies. ESC Heart Fail 2020; 7: 1387–1399.

27.

Ferhat

Karabekir

Gultekin

, et al. Evaluation of the relationship between anti-inflammatory cytokines and adverse cardiac remodeling after myocardial infarction. Kardiologiia 2021; 61: 61–70.

28.

Zouggari

Ait-Oufella

Bonnin

, et al. B lymphocytes trigger monocyte mobilization and impair heart function after acute myocardial infarction. Nat Med 2013; 19: 1273–1280.

29.

Horckmans

Bianchini

Santovito

, et al. Pericardial adipose tissue regulates granulopoiesis, fibrosis, and cardiac function after myocardial infarction. Circulation 2018; 137: 948–960.

30.

Cordero-Reyes

Youker

Trevino

, et al. Full expression of cardiomyopathy is partly dependent on B-cells: a pathway that involves cytokine activation, immunoglobulin deposition, and activation of apoptosis. J Am Heart Assoc 2016; 5: e002484.