Single cell sequencing reveals endothelial plasticity with transient mesenchymal activation after myocardial infarction

Lukas Tombor ,David John,Richard P Harvey,Guillermo Luxán,Kathrin Klee,Mario Looso,Yosif Manavski,Sofia-Iris Bibli,Elvira Forte,Janina Wittig,Nadia Rosenthal,Ralph Patrick,Till Acker,Nina Baumgarten,Marcel H Schulz,Marion Muhly-Reinholz,Carmen Selignow,Simone F Glaser,Ariane Fischer,Milena B Furtado ,Wesley Abplanalp ,Eva-Maria Rogg,Ingrid Fleming,Stefanie Dimmeler

doi:10.1038/s41467-021-20905-1

Abstract

Endothelial cells play a critical role in the adaptation of tissues to injury. Tissue ischemia induced by infarction leads to profound changes in endothelial cell functions and can induce transition to a mesenchymal state. Here we explore the kinetics and individual cellular responses of endothelial cells after myocardial infarction by using single cell RNA sequencing. This study demonstrates a time dependent switch in endothelial cell proliferation and inflammation associated with transient changes in metabolic gene signatures. Trajectory analysis reveals that the majority of endothelial cells 3 to 7 days after myocardial infarction acquire a transient state, characterized by mesenchymal gene expression, which returns to baseline 14 days after injury. Lineage tracing, using the Cdh5-CreERT2;mT/mG mice followed by single cell RNA sequencing, confirms the transient mesenchymal transition and reveals additional hypoxic and inflammatory signatures of endothelial cells during early and late states after injury. These data suggest that endothelial cells undergo a transient mes-enchymal activation concomitant with a metabolic adaptation within the first days after myocardial infarction but do not acquire a long-term mesenchymal fate. This mesenchymal activation may facilitate endothelial cell migration and clonal expansion to regenerate the vascular network.

Highlights

Endothelial cells play a critical role in the adaptation of tissues to injury
The increase in Endothelial cells (ECs) proliferation was confirmed by bioinformatic analysis of cell cycle phases showing an increase in expression of cell cycle genes and number of ECs in S-phase at day 3, which is returned to homeostatic levels at day 14 after myocardial infarction (MI) (Fig. 1f, g)
We demonstrate that ECs undergo a transient mesenchymal activation that is associated with profound metabolic adaptations (Supplementary Fig. 18)

Summary

Introduction

Endothelial cells play a critical role in the adaptation of tissues to injury. Tissue ischemia induced by infarction leads to profound changes in endothelial cell functions and can induce transition to a mesenchymal state. Lineage tracing, using the Cdh5-CreERT2;mT/mG mice followed by single cell RNA sequencing, confirms the transient mesenchymal transition and reveals additional hypoxic and inflammatory signatures of endothelial cells during early and late states after injury. These data suggest that endothelial cells undergo a transient mesenchymal activation concomitant with a metabolic adaptation within the first days after myocardial infarction but do not acquire a long-term mesenchymal fate. Phenotypic changes are facilitated by high low-density lipoprotein (LDL) cholesterol, a pro-inflammatory state and turbulent flow patterns leading to endothelial activation This contributes to the impairment of the vasodilatory activity (so called “endothelial dysfunction”), which plays a key role in the development of atherosclerotic lesions[7]. We show the adaptive responses of ECs to cardiac ischemia by using single-cell technology, a powerful tool capable of deciphering individual cellular responses and transcriptional signatures within tissue

Methods

Results

Conclusion