Defining cardiac cell populations and relative cellular composition of the early fetal human heart.

While the adult human heart is primarily composed of cardiomyocytes, fibroblasts, endothelial and smooth muscle cells, the cellular composition during early development remains largely unknown. Reliable identification of fetal cardiac cell types using protein markers is critical to understand cardia...

Full description

Bibliographic Details
Main Authors: Jennifer M Dewing, Vinay Saunders, Ita O'Kelly, David I Wilson
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2022-01-01
Series:PLoS ONE
Online Access:https://doi.org/10.1371/journal.pone.0259477
_version_ 1797978116023386112
author Jennifer M Dewing
Vinay Saunders
Ita O'Kelly
David I Wilson
author_facet Jennifer M Dewing
Vinay Saunders
Ita O'Kelly
David I Wilson
author_sort Jennifer M Dewing
collection DOAJ
description While the adult human heart is primarily composed of cardiomyocytes, fibroblasts, endothelial and smooth muscle cells, the cellular composition during early development remains largely unknown. Reliable identification of fetal cardiac cell types using protein markers is critical to understand cardiac development and delineate the cellular composition of the developing human heart. This is the first study to use immunohistochemistry (IHC), flow cytometry and RT-PCR analyses to investigate the expression and specificity of commonly used cardiac cell markers in the early human fetal heart (8-12 post-conception weeks). The expression of previously reported protein markers for the detection of cardiomyocytes (Myosin Heavy Chain (MHC) and cardiac troponin I (cTnI), fibroblasts (DDR2, THY1, Vimentin), endothelial cells (CD31) and smooth muscle cells (α-SMA) were assessed. Two distinct populations of cTnI positive cells were identified through flow cytometry, with MHC positive cardiomyocytes showing high cTnI expression (cTnIHigh) while MHC negative non-myocytes showed lower cTnI expression (cTnILow). cTnI expression in non-myocytes was further confirmed by IHC and RT-PCR analyses, suggesting troponins are not cardiomyocyte-specific and may play distinct roles in non-muscle cells during early development. Vimentin (VIM) was expressed in cultured ventricular fibroblast populations and flow cytometry revealed VIMHigh and VIMLow cell populations in the fetal heart. MHC positive cardiomyocytes were VIMLow whilst CD31 positive endothelial cells were VIMHigh. Using markers investigated within this study, we characterised fetal human cardiac populations and estimate that 75-80% of fetal cardiac cells are cardiomyocytes and are MHC+/cTnIHigh/VIMLow, whilst non-myocytes comprise 20-25% of total cells and are MHC-/cTnILow/VIMHigh, with CD31+ endothelial cells comprising ~9% of this population. These findings show distinct differences from those reported for adult heart.
first_indexed 2024-04-11T05:17:55Z
format Article
id doaj.art-eb68cef7b14047f0a3f3f72c05deb838
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-04-11T05:17:55Z
publishDate 2022-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-eb68cef7b14047f0a3f3f72c05deb8382022-12-24T05:32:31ZengPublic Library of Science (PLoS)PLoS ONE1932-62032022-01-011711e025947710.1371/journal.pone.0259477Defining cardiac cell populations and relative cellular composition of the early fetal human heart.Jennifer M DewingVinay SaundersIta O'KellyDavid I WilsonWhile the adult human heart is primarily composed of cardiomyocytes, fibroblasts, endothelial and smooth muscle cells, the cellular composition during early development remains largely unknown. Reliable identification of fetal cardiac cell types using protein markers is critical to understand cardiac development and delineate the cellular composition of the developing human heart. This is the first study to use immunohistochemistry (IHC), flow cytometry and RT-PCR analyses to investigate the expression and specificity of commonly used cardiac cell markers in the early human fetal heart (8-12 post-conception weeks). The expression of previously reported protein markers for the detection of cardiomyocytes (Myosin Heavy Chain (MHC) and cardiac troponin I (cTnI), fibroblasts (DDR2, THY1, Vimentin), endothelial cells (CD31) and smooth muscle cells (α-SMA) were assessed. Two distinct populations of cTnI positive cells were identified through flow cytometry, with MHC positive cardiomyocytes showing high cTnI expression (cTnIHigh) while MHC negative non-myocytes showed lower cTnI expression (cTnILow). cTnI expression in non-myocytes was further confirmed by IHC and RT-PCR analyses, suggesting troponins are not cardiomyocyte-specific and may play distinct roles in non-muscle cells during early development. Vimentin (VIM) was expressed in cultured ventricular fibroblast populations and flow cytometry revealed VIMHigh and VIMLow cell populations in the fetal heart. MHC positive cardiomyocytes were VIMLow whilst CD31 positive endothelial cells were VIMHigh. Using markers investigated within this study, we characterised fetal human cardiac populations and estimate that 75-80% of fetal cardiac cells are cardiomyocytes and are MHC+/cTnIHigh/VIMLow, whilst non-myocytes comprise 20-25% of total cells and are MHC-/cTnILow/VIMHigh, with CD31+ endothelial cells comprising ~9% of this population. These findings show distinct differences from those reported for adult heart.https://doi.org/10.1371/journal.pone.0259477
spellingShingle Jennifer M Dewing
Vinay Saunders
Ita O'Kelly
David I Wilson
Defining cardiac cell populations and relative cellular composition of the early fetal human heart.
PLoS ONE
title Defining cardiac cell populations and relative cellular composition of the early fetal human heart.
title_full Defining cardiac cell populations and relative cellular composition of the early fetal human heart.
title_fullStr Defining cardiac cell populations and relative cellular composition of the early fetal human heart.
title_full_unstemmed Defining cardiac cell populations and relative cellular composition of the early fetal human heart.
title_short Defining cardiac cell populations and relative cellular composition of the early fetal human heart.
title_sort defining cardiac cell populations and relative cellular composition of the early fetal human heart
url https://doi.org/10.1371/journal.pone.0259477
work_keys_str_mv AT jennifermdewing definingcardiaccellpopulationsandrelativecellularcompositionoftheearlyfetalhumanheart
AT vinaysaunders definingcardiaccellpopulationsandrelativecellularcompositionoftheearlyfetalhumanheart
AT itaokelly definingcardiaccellpopulationsandrelativecellularcompositionoftheearlyfetalhumanheart
AT davidiwilson definingcardiaccellpopulationsandrelativecellularcompositionoftheearlyfetalhumanheart