Single-Cell Analysis of Aneurysmal Aortic Tissue in Patients with Marfan Syndrome Reveals Dysfunctional TGF-β Signaling

The molecular and cellular processes leading to aortic aneurysm development in Marfan syndrome (MFS) remain poorly understood. In this study, we examined the changes of aortic cell populations and gene expression in MFS by performing single-cell RNA sequencing (scRNA seq) on ascending aortic aneurysm tissues from patients with MFS (n = 3) and age-matched non-aneurysmal control tissues from cardiac donors and recipients (n = 4). The expression of key molecules was confirmed by immunostaining. We detected diverse populations of smooth muscle cells (SMCs), fibroblasts, and endothelial cells (ECs) in the aortic wall. Aortic tissues from MFS showed alterations of cell populations with increased de-differentiated proliferative SMCs compared to controls. Furthermore, there was a downregulation of MYOCD and MYH11 in SMCs, and an upregulation of COL1A1/2 in fibroblasts in MFS samples compared to controls. We also examined TGF-β signaling, an important pathway in aortic homeostasis. We found that TGFB1 was significantly upregulated in two fibroblast clusters in MFS tissues. However, TGF-β receptor genes (predominantly TGFBR2) and SMAD genes were downregulated in SMCs, fibroblasts, and ECs in MFS, indicating impairment in TGF-β signaling. In conclusion, despite upregulation of TGFB1, the rest of the canonical TGF-β pathway and mature SMCs were consistently downregulated in MFS, indicating a potential compromise of TGF-β signaling and lack of stimulus for SMC differentiation.

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Abstract 15530: Single-cell Analysis in Aortic Aneurysmal Tissue From Patients With Marfan Syndrome Reveals Increased Tgf-beta Production but Downregulation of Downstream Canonical Tgf-beta Signaling Pathways

Circulation ◽

10.1161/circ.142.suppl_3.15530 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Ashley Dawson ◽

Yanming Li ◽

Pingping Ren ◽

Hernan Vasquez ◽

Chen Zhang ◽

...

Keyword(s):

Aortic Aneurysm ◽

Single Cell ◽

Marfan Syndrome ◽

Immune Cells ◽

Single Cell Analysis ◽

Aortic Aneurysms ◽

Differentially Expressed ◽

Aortic Tissue ◽

Cardiac Transplant ◽

Tgf Beta

Background: Marfan syndrome (MFS) is caused by mutations in the gene for fibrillin-1 ( FBN1 ); however, the mechanisms by which these mutations cause aortic aneurysms are poorly understood. Although it was hypothesized previously that dysregulation of the complex TGF-β signaling pathway leads to aortic aneurysm formation, FBN1 mutations appear to have a paradoxical effect on TGF-β signaling in MFS. In this study, we evaluated cell-specific TGF-β expression in non-immune cells in MFS aortic tissue. Methods: We performed single-cell RNA sequencing of ascending aortic aneurysm tissues from MFS patients (n=3) undergoing aneurysm repair and age-matched, non-aneurysmal control tissue from cardiac transplant donors and recipients (n=4). Non-immune cells were separated out from the data and analyzed using the Seurat package in R. Differentially expressed genes were identified using edgeR. Results: Conserved gene expression was used to identify populations of smooth muscle cells (SMCs; n=6), fibroblasts (n=3), and endothelial cells (ECs; n=3). We found that TGFB1 was significantly upregulated in quiescent fibroblasts (identified by increased expression of DCN , LUM , and complement factors) with log2FC of 1.30 and FDR 8.25x10 -8 , as well as in activated fibroblasts (identified by increased expression of genes involved in blood vessel repair and healing including ACTA2 , NOTCH3 , THBS2 , and PDGFRB ) with log2FC of 1.25 and FDR 6.15x10 -22 . Despite this increase in TGFB1 , expression of TGF-β receptor genes (predominately TGFBR2 ) as well as downstream SMAD genes was downregulated significantly in the SMC, fibroblast, and endothelial cell clusters. Finally, genes involved in the non-canonical TGF-β pathway, including ERK , JNK, and p38, were not differentially expressed in non-immune cells in MFS compared with control tissues. Conclusion: Increased expression of TGFB1 in non-immune cells in MFS was driven by two clusters of fibroblasts. Despite this, our data do not support associated upregulation of other genes in the canonical or non-canonical TGF-β pathways and in fact support downregulation of canonical TGF-β signaling in non-immune cells of aneurysmal tissues from MFS patients with advanced aortic disease.

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Single-Cell Analysis of the Normal Mouse Aorta Reveals Functionally Distinct Endothelial Cell Populations

Circulation ◽

10.1161/circulationaha.118.038362 ◽

2019 ◽

Vol 140 (2) ◽

pp. 147-163 ◽

Cited By ~ 44

Author(s):

Aditya S. Kalluri ◽

Shamsudheen K. Vellarikkal ◽

Elazer R. Edelman ◽

Lan Nguyen ◽

Ayshwarya Subramanian ◽

...

Keyword(s):

Endothelial Cell ◽

Single Cell ◽

Normal Mouse ◽

Single Cell Analysis ◽

Cell Populations ◽

Cell Analysis ◽

Mouse Aorta

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Multi-omic single cell analysis resolves novel stromal cell populations in healthy and diseased human tendon

Scientific Reports ◽

10.1038/s41598-020-70786-5 ◽

2020 ◽

Vol 10 (1) ◽

Cited By ~ 2

Author(s):

Adrian R. Kendal ◽

Thomas Layton ◽

Hussein Al-Mossawi ◽

Louise Appleton ◽

Stephanie Dakin ◽

...

Keyword(s):

Single Cell ◽

Stromal Cell ◽

Single Cell Analysis ◽

Cell Populations ◽

Cell Analysis ◽

Human Tendon

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158 Single cell analysis of emigrating cells from psoriasis lesion identifies distinct IL-17A and IL-17F producing T-cell populations and other novel disease-associated alterations

Journal of Investigative Dermatology ◽

10.1016/j.jid.2020.03.162 ◽

2020 ◽

Vol 140 (7) ◽

pp. S19

Author(s):

J. Kim ◽

J. Lee ◽

H. Kim ◽

N. Kameyama ◽

R. Nazarian ◽

...

Keyword(s):

T Cell ◽

Single Cell ◽

Single Cell Analysis ◽

Cell Populations ◽

Cell Analysis ◽

Psoriasis Lesion

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Single-Cell RNA Sequencing Defines the Regulation of Spermatogenesis by Sertoli-Cell Androgen Signaling

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.763267 ◽

2021 ◽

Vol 9 ◽

Author(s):

Congcong Cao ◽

Qian Ma ◽

Shaomei Mo ◽

Ge Shu ◽

Qunlong Liu ◽

...

Keyword(s):

Single Cell ◽

Sertoli Cells ◽

Molecular Mechanisms ◽

Cell Types ◽

Cellular Heterogeneity ◽

Cell Populations ◽

Wild Type ◽

Cellular Processes ◽

Transcriptomic Sequencing ◽

Transcriptional Changes

Androgen receptor (AR) signaling is essential for maintaining spermatogenesis and male fertility. However, the molecular mechanisms by which AR acts between male germ cells and somatic cells during spermatogenesis have not begun to be revealed until recently. With the advances obtained from the use of transgenic mice lacking AR in Sertoli cells (SCARKO) and single-cell transcriptomic sequencing (scRNA-seq), the cell specific targets of AR action as well as the genes and signaling pathways that are regulated by AR are being identified. In this study, we collected scRNA-seq data from wild-type (WT) and SCARKO mice testes at p20 and identified four somatic cell populations and two male germ cell populations. Further analysis identified that the distribution of Sertoli cells was completely different and uncovered the cellular heterogeneity and transcriptional changes between WT and SCARKO Sertoli cells. In addition, several differentially expressed genes (DEGs) in SCARKO Sertoli cells, many of which have been previously implicated in cell cycle, apoptosis and male infertility, have also been identified. Together, our research explores a novel perspective on the changes in the transcription level of various cell types between WT and SCARKO mice testes, providing new insights for the investigations of the molecular and cellular processes regulated by AR signaling in Sertoli cells.

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