id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-310124-3bc8zeww	Ratajczak, Mariusz Z.	SARS-CoV-2 Entry Receptor ACE2 Is Expressed on Very Small CD45(−) Precursors of Hematopoietic and Endothelial Cells and in Response to Virus Spike Protein Activates the Nlrp3 Inflammasome	2020-07-20		.txt	text/plain	5165	281	52	We demonstrate for the first time that ACE2 and the entry-facilitating transmembrane protease TMPRSS2 are expressed on very small CD133(+)CD34(+)Lin(−)CD45(−) cells in human umbilical cord blood (UCB), which can be specified into functional HSCs and EPCs. The existence of these cells known as very small embryonic-like stem cells (VSELs) has been confirmed by several laboratories, and some of them may correspond to putative postnatal hemangioblasts. Moreover, we demonstrate for the first time that, in human VSELs and HSCs, the interaction of the ACE2 receptor with the SARS-CoV-2 spike protein activates the Nlrp3 inflammasome, which if hyperactivated may lead to cell death by pyroptosis. We sorted very small CD34 + Lin − CD45 − cells (VSELs) and CD34 + Lin − CD45 + cells (HSCs) from UCB by FACS (Fig. 1) and phenotyped them by real-time PCR for expression of mRNAs for the ACE2 entry receptor for SARS-CoV-2, the spike protein-processing enzyme TIMPRSS2, the receptors for Ang II (AT 1 R and AT 2 R), and the Ang (1-7) receptor (MasR, Fig. 2) .	./cache/cord-310124-3bc8zeww.txt	./txt/cord-310124-3bc8zeww.txt