Peculiarities of dissection of rat pericardium and study of its lymphoid           component

Oksana  Kushch; Danyil  Kucherov

doi:10.32345/SUPPLEMENT.2.2025.314-319

Oksana Kushch Zaporizhzhia National University, Zaporizhzhia, Ukraine https://orcid.org/0000-0003-3827-3752
Danyil Kucherov Zaporizhzhia National University, Zaporizhzhia, Ukraine

DOI: https://doi.org/10.32345/SUPPLEMENT.2.2025.314-319

Keywords: Cardiovascular system; rat; pericardium; pericardium; fibrous layer; histology; morphology; mesothelium; lymphocyte

Abstract

Today, the structure of the medulla remains an important open question in immunomorphology: the morphological equivalents of the three main functional groups of lymphocytes of innate immunity have not yet been identified. The lack of clear morphological markers of these lymphocytes complicates the study of their localization, differentiation and functional activity within the medulla tissues. This issue creates a significant gap in modern ideas about the immune microorganism of the heart. It has been proven that representatives of nonspecific immunity play a certain physiological role in the functions of the parietal pericardium: γδ-T lymphocytes and B1 lymphocytes. However, their topography, morphology and dynamics of the number in the experiment and in pathology remain poorly studied. The aim of the study was: to develop and optimize the method of preparing the medulla of rats in order to provide access to the medulla without tissue damage; determination of the morphological characteristics of the lymphoid component of the medulla in laboratory rats; assessment of the localization and structure of lymphoid elements in the fibrous leaf of the medulla; study of the functional features of the lymphoid apparatus of the medulla under normal conditions as a basis for further comparisons in experimental models of heart pathologies, which can be used as reference values in the study of experimental models of cardiovascular diseases. Research results. The following cellular composition was found in the medulla of white rats in the norm: macrophages, small lymphocytes, medium lymphocytes, broad-plasma lymphocytes, fibroblasts. The lymphoid tissue of the medulla is represented by diffuse lymphoid tissue and clusters of 5-8 lymphocytes forming clusters. The results obtained can serve as a morphological reference point for further experimental studies in the field of immunocardiology, in particular for the assessment of pathological changes in the medulla. Despite the presence of morphologically verified immunocompetent cells in the structure of the pericardium, the question of their functional activity, phenotypic diversity and role in maintaining immune balance both in physiological conditions and in pathology remains insufficiently studied.

References

Horckmans M, Bianchini M, Santovito D, et al. Pericardial adipose tissue regulates granulopoiesis, fibrosis, and cardiac function after myocardial infarction. Circulation. 2018;137(9):948–60.

Benhaiem-Sigaux N, Mina E, Sigaux F, et al. Characterization of human pericardial macrophages. J Leukoc Biol. 1985;38:709–21.

Gordon S, Plüddemann A. Tissue macrophages: heterogeneity and functions. BMC Biol. 2017;15:53.

Wang J, Kubes P. A reservoir of mature cavity macrophages that can rapidly invade visceral organs to affect tissue repair. Cell. 2016;165:668–78.

Okabe Y, Medzhitov R. Tissue-specific signals control reversible program of localization and functional polarization of macrophages. Cell. 2014;157:832–44.

Toor IS, Rückerl D, Mair I, et al. Eosinophil deficiency promotes aberrant repair and adverse remodeling following acute myocardial infarction. JACC Basic Transl Sci. 2020;5:665–81.

Benezech C, Luu NT, Walker JA, et al. Inflammation-induced formation of fat-associated lymphoid clusters. Nat Immunol. 2015;16:819–28.

Jackson-Jones LH, Duncan SM, Magalhaes MS, et al. Fat-associated lymphoid clusters control local IgM secretion during pleural infection and lung inflammation. Nat Commun. 2016;7:12651.

Isidoro CA, Deniset JF. Pericardial immune cells and their evolving role in cardiovascular pathophysiology. Trends Immunol. 2023;39(8):1078–89.

Choi HS, Won T, Hou X, Chen G, Bracamonte-Baran W, Talor MV, et al. Innate lymphoid cells play a pathogenic role in pericarditis. Cell Rep. 2020;30(9):2989–3003.e6.

Кущ ОГ, Пайдаркіна АП. Усучаснений погляд на морфологію очеревини та її ремоделювання за спайкової хвороби. Наук Вісник Ужгород ун-ту (Сер Біол). 2023;55:50–61.

Jackson-Jones LH, Mylonas KJ, Andrews JPM, et al. Pericardium promotes cardiac repair and remodelling post-myocardial infarction [preprint]. bioRxiv. 2019. Available from: https://www.biorxiv.org/content/10.1101/771154v1.

Bentkowska K, Hardgrave A, Iqbal N, Gresty L, Marsden B, Macharia S, Jackson-Jones L. Pericardial and mediastinal fat-associated lymphoid clusters are rapidly activated in an alkane-induced model of systemic lupus erythematosus. Discov Immunol. 2023;2:1–9.

Пайдаркіна АП, Кущ ОГ. Особливості топографії і кількості SBA+-В-лімфоцитів в брижі кишківника в нормі та при формуванні спайкового процесу. Біологія та екологія. 2024;1:125–30.

Кущ ОГ, Пайдаркіна АП. Ремоделювання очеревини і зміни її лімфоїдного компоненту при експериментальному моделюванні спайкової хвороби у щурів. Sci J ScienceRise Biol Sci. 2024;1(38):10–16.

Bruno KA, Mathews JE, Yang AL, et al. BPA alters estrogen receptor expression in the heart after viral infection activating cardiac mast cells and T cells leading to perimyocarditis and fibrosis. Front Endocrinol (Lausanne). 2019;10:598.

Buechler MB, Kim KW, Onufer EJ, et al. A stromal niche defined by expression of the transcription factor WT1 mediates programming and homeostasis of cavity-resident macrophages. Immunity. 2019;51(1):119–130.e5.

Choi HS, Won T, Hou X, Chen G, Bracamonte-Baran W, Talor MV, et al. Innate lymphoid cells play a pathogenic role in pericarditis. Cell Rep. 2020;30(9):2989–3003.e6.

Domínguez Conde C, Xu C, Jarvis LB, et al. Cross-tissue immune cell analysis reveals tissue-specific features in humans. Science. 2022;376:eabl5197.

Isidoro CA, Deniset JF. The role of macrophage subsets in and around the heart in modulating cardiac homeostasis and pathophysiology. Front Immunol. 2023;14:1111819.

Leuschner F, Nahrendorf M. Novel functions of macrophages in the heart: insights into electrical conduction, stress, and diastolic dysfunction. Eur Heart J. 2020;41:989–94.

Meher AK, McNamara CA. B1-lymphocytes in adipose tissue as innate modulators of inflammation linked to cardiometabolic disease. Immunol Rev. 2024;324(1):95–103.

Yu X, Newland SA, Zhao TX, et al. Innate lymphoid cells promote recovery of ventricular function after myocardial infarction. J Am Coll Cardiol. 2021;78:1127.

Zaman R, Epelman S. Resident cardiac macrophages: heterogeneity and function in health and disease. Immunity. 2022;55:1549–63.

Кущ ОГ, Пайдаркіна АП. Ремоделювання очеревини і зміни її лімфоїдного компоненту при експериментальному моделюванні спайкової хвороби у щурів. Sci J ScienceRise Biol Sci. 2024;1(38):10–16.

Peculiarities of dissection of rat pericardium and study of its lymphoid component

Abstract

References

Most read articles by the same author(s)