Inhibition of Murine Pulmonary Microvascular Endothelial Cell Apoptosis Promotes Recovery of Barrier Function under Septic Conditions

Table 1

Review of literature on relationship of endothelial cell apoptosis and barrier dysfunction in vitro.

Citation	Species	EC type	EC identification method	Septic treatment	Markers of apoptosis	Measure of trans-EC leak	Leak-apoptosis relationship	Comments
Bannerman et al. 1998 [27]	Bovine	Commercial; PAEC cell line	—	LPS	DNA laddering; TUNEL	14C-albumin	+/−	Similar time course of leak and apoptosis; apoptosis inhibition (zVAD) did not affect leak
Petrache et al. 2003 [28]	Bovine	Commercial; PAEC cell line	—	TNFα	Annexin V; DNA laddering; cleaved caspase 8	TEER	+/−	Apoptosis inhibition (zVAD) treatment inhibited leak; MLCK inhibition reduced apoptosis but did not affect leak
Petrache et al. 2001 [29]	Human	Commercial PAEC	—	TNFα	Nucleosome ELISA	TEER	No	No apoptosis observed
Liu et al. 2005 [30]	Human	Commercial HUVEC	—	LPS	DNA fragmentation; Annexin V	EB-albumin	+/−	Time-dependent relationship: leak at all time points, apoptosis only at later time points
Seynhaeve et al. 2006 [31]	Human	Primary HUVEC	Morphology; CD31	TNFα, IL1β, IFNγ	Annexin V; YO-PRO-1	FITC-albumin	+/−	Variable leak-apoptosis relationship depending on combinations of different cytokines
Cardoso et al. 2012 [32]	Rat	Primary; brain MVEC	None	LPS	Nuclear morphology; caspase 3 activity	TEER; fluorescein	+/−	Leak-apoptosis correlation following LPS + other inflammatory stimuli, not LPS alone
Lopez-Ramirez et al. 2012 [33]	Human	Commercial brain MVEC	—	TNFα, IFNγ	Annexin V; caspase 3/7 activity; TUNEL	TEER, FITC-dextran	+/−	Apoptosis inhibition (specific caspase inhibitors) only partially rescued leak; apoptosis only assessed at single time point
Abdullah and Bayraktutan 2014 [34]	Human	Commercial; brain MVEC	—	TNFα	TUNEL; caspase 3/7 activity	TEER; EB-albumin	+/−	Leak and apoptosis early; leak recovers at later time points but apoptosis increases
Bechelli et al. 2015 [35]	Human	Commercial dermal MVEC cell line	—	Rickettsia conorii	Annexin V	TEER	No	Leak occurs before apoptosis; markers of other types of cell death present
Yang et al. 2015 [36]	Human	Commercial pulmonary MVEC	—	LPS	Annexin V	FITC-dextran; FITC-albumin	+/−	Association at a single time point; some conditions had different effects on apoptosis and leak
Wagner et al. 2016 [37]	Human	Commercial HUVEC	—	TNFα; procalcitonin	Annexin V	FITC-dextran	+/−	Leak early at low dose; apoptosis present later at high dose
McDonnell et al. 2016 [38]	Human	Primary AoEC	None	Staphylococcus aureus	Annexin V	FITC-dextran	Yes	Association at only a single time point
Zhu et al. 2016 [39]	Human	Commercial HUVEC	—	TNFα and CXCL10	Cleaved caspase 3	TEER	Yes	Association at only a single time point
Wang et al. 2017 (present study)	Mouse	Primary; pulmonary MVEC	CD31, CD34, CD176, CD202b	TNFα, IL1β, IFNγ	Annexin V; FLICA (pan-caspase activity); TUNEL	TEER, EB-albumin	Yes	Time-dependent relationship: early leak apoptosis-independent; delayed leak apoptosis-dependent

Aortic endothelial cells, AoEC; C-X-C motif chemokine 10, CXCL10; Evans blue dye, EB; endothelial cell, EC; enzyme-linked immunosorbent assay, ELISA; fluorescein isothiocyanate, FITC; human umbilical vein endothelial cell, HUVEC; interferon gamma, IFNγ; interleukin 1 beta, IL1β; lipopolysaccharide, LPS; microvascular endothelial cell, MVEC; myosin light-chain kinase, MLCK; pulmonary artery endothelial cells, PAEC; transendothelial electrical resistance, TEER; tumour necrosis factor alpha, TNFα; terminal deoxynucleotidyl transferase dUTP nick end labeling, TUNEL; carbobenzoxy-valyl-alanyl-aspartyl-O-methyl, zVAD; +/−, inconsistent/variable association.