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Biology subjects

See, M.

Publications and source records attributed to See, M..

2 recordsLinked to original sources

Parallel use of pluripotent human stem cell lung and heart models provide new insights for treatment of SARS-CoV-2

SARS-CoV-2 primarily infects the respiratory tract, but pulmonary and cardiac complications occur in severe COVID-19. To elucidate molecular mechanisms in the lung and heart, we conducted paired experiments in human stem cell-derived lung alveolar type II (AT2) epithelial cell and cardiac cultures infected with SARS-CoV-2. With CRISPR- Cas9 mediated knock-out of ACE2, we demonstrated that angiotensin converting enzyme 2 (ACE2) was essential for SARS-CoV-2 infection of both cell types but further processing in lung cells required TMPRSS2 while cardiac cells required the endosomal pathway. Host responses were significantly different; transcriptome profiling and phosphoproteomics responses depended strongly on the cell type. We identified several antiviral compounds with distinct antiviral and toxicity profiles in lung AT2 and cardiac cells, highlighting the importance of using several relevant cell types for evaluation of antiviral drugs. Our data provide new insights into rational drug combinations for effective treatment of a virus that affects multiple organ systems. One-sentence summaryRational treatment strategies for SARS-CoV-2 derived from human PSC models

microbiology↗

The human FLT1 regulatory element directs vascular expression and modulates angiogenesis pathways in vitro and in vivo

There is growing evidence that mutations in non-coding cis-regulatory elements (CREs) disrupt proper development. However, little is known about human CREs that are crucial for cardiovascular development. To address this, we bioinformatically identified cardiovascular CREs based on the occupancy of the CRE by the homeodomain protein NKX2-5 and cardiac chromatin histone modifications. This search defined a highly conserved CRE within the FLT1 locus termed enFLT1. We show that the human enFLT1 is an enhancer capable of driving reporter transgene expression in vivo throughout the developing cardiovascular system of medaka. Deletion of the human enFLT1 enhancer ({Delta}enFLT1) triggered molecular perturbations in extracellular matrix organisation and blood vessel morphogenesis in vitro in endothelial cells derived from human embryonic stem cells and vascular defects in vivo in medaka. These findings highlight the crucial role of the human FLT1 enhancer and its function as a regulator and buffer of transcriptional regulation in cardiovascular development.

genomics↗