scholarly journals Endothelial Claudin

1999 ◽  
Vol 147 (1) ◽  
pp. 185-194 ◽  
Author(s):  
Kazumasa Morita ◽  
Hiroyuki Sasaki ◽  
Mikio Furuse ◽  
Shoichiro Tsukita
Keyword(s):  
Endothelial Cells ◽  
Epithelial Cells ◽  
Blood Vessels ◽  
Polyclonal Antibody ◽  
Polyclonal Antibodies ◽  
Transmembrane Protein ◽  
Velo Cardio Facial Syndrome ◽  
The Brain ◽  
Specific Polyclonal Antibody

Tight junctions (TJs) in endothelial cells are thought to determine vascular permeability. Recently, claudin-1 to -15 were identified as major components of TJ strands. Among these, claudin-5 (also called transmembrane protein deleted in velo-cardio-facial syndrome [TMVCF]) was expressed ubiquitously, even in organs lacking epithelial tissues, suggesting the possible involvement of this claudin species in endothelial TJs. We then obtained a claudin-6–specific polyclonal antibody and a polyclonal antibody that recognized both claudin-5/TMVCF and claudin-6. In the brain and lung, immunofluorescence microscopy with these polyclonal antibodies showed that claudin-5/TMVCF was exclusively concentrated at cell–cell borders of endothelial cells of all segments of blood vessels, but not at those of epithelial cells. Immunoreplica electron microscopy revealed that claudin-5/TMVCF was a component of TJ strands. In contrast, in the kidney, the claudin-5/TMVCF signal was restricted to endothelial cells of arteries, but was undetectable in those of veins and capillaries. In addition, in all other tissues we examined, claudin-5/TMVCF was specifically detected in endothelial cells of some segments of blood vessels, but not in epithelial cells. Furthermore, when claudin-5/TMVCF cDNA was introduced into mouse L fibroblasts, TJ strands were reconstituted that resembled those in endothelial cells in vivo, i.e., the extracellular face–associated TJs. These findings indicated that claudin-5/TMVCF is an endothelial cell–specific component of TJ strands.

scholarly journals The Ability of Zika virus Intravenous Immunoglobulin to Protect From or Enhance Zika Virus Disease

2021 ◽  
Vol 12 ◽  
Author(s):  
Amelia K. Pinto ◽  
Mariah Hassert ◽  
Xiaobing Han ◽  
Douglas Barker ◽  
Trevor Carnelley ◽  
...  
Keyword(s):  
Virus Infection ◽  
Polyclonal Antibody ◽  
Zika Virus ◽  
Virus Disease ◽  
Polyclonal Antibodies ◽  
Antibody Therapeutics ◽  
The World ◽  
Flavivirus Infection

The closely related flaviviruses, dengue and Zika, cause significant human disease throughout the world. While cross-reactive antibodies have been demonstrated to have the capacity to potentiate disease or mediate protection during flavivirus infection, the mechanisms responsible for this dichotomy are still poorly understood. To understand how the human polyclonal antibody response can protect against, and potentiate the disease in the context of dengue and Zika virus infection we used intravenous hyperimmunoglobulin (IVIG) preparations in a mouse model of the disease. Three IVIGs (ZIKV-IG, Control-Ig and Gamunex®) were evaluated for their ability to neutralize and/or enhance Zika, dengue 2 and 3 viruses in vitro. The balance between virus neutralization and enhancement provided by the in vitro neutralization data was used to predict the IVIG concentrations which could protect or enhance Zika, and dengue 2 disease in vivo. Using this approach, we were able to define the unique in vivo dynamics of complex polyclonal antibodies, allowing for both enhancement and protection from flavivirus infection. Our results provide a novel understanding of how polyclonal antibodies interact with viruses with implications for the use of polyclonal antibody therapeutics and the development and evaluation of the next generation flavivirus vaccines.

scholarly journals Human Cytomegalovirus Cell Tropism and Host Cell Receptors

Vaccines ◽  
2019 ◽  
Vol 7 (3) ◽  
pp. 70 ◽  
Author(s):  
Gerna ◽  
Kabanova ◽  
Lilleri
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Epithelial Cells ◽  
Human Cytomegalovirus ◽  
Current Data ◽  
Immunosuppressed Patient ◽  
Cell Tropism ◽  
Virus Envelope

In the 1970s–1980s, a striking increase in the number of disseminated human cytomegalovirus (HCMV) infections occurred in immunosuppressed patient populations. Autopsy findings documented the in vivo disseminated infection (besides fibroblasts) of epithelial cells, endothelial cells, and polymorphonuclear leukocytes. As a result, multiple diagnostic assays, such as quantification of HCMV antigenemia (pp65), viremia (infectious virus), and DNAemia (HCMV DNA) in patient blood, were developed. In vitro experiments showed that only low passage or endothelial cell-passaged clinical isolates, and not laboratory-adapted strains, could reproduce both HCMV leuko- and endothelial cell-tropism, which were found through genetic analysis to require the three viral genes UL128, UL130, and UL131 of the HCMV UL128 locus (UL128L). Products of this locus, together with gH/gL, were shown to form the gH/gL/pUL128L pentamer complex (PC) required for infection of epithelial cells/endothelial cells, whereas gH/gL and gO form the gH/gL/gO trimer complex (TC) required for infection of all cell types. In 2016, following previous work, a receptor for the TC that mediates entry into fibroblasts was identified as PDGFRα, while in 2018, a receptor for the PC that mediates entry into endothelial/epithelial cells was identified as neuropilin2 (Nrp2). Furthermore, the olfactory receptor family member OR14I1 was recently identified as a possible additional receptor for the PC in epithelial cells. Thus, current data support two models of viral entry: (i) in fibroblasts, following interaction of PDGFRα with TC, the latter activates gB to fuse the virus envelope with the cell membrane, whereas (ii) in epithelial cells/endothelial cells, interaction of Nrp2 (and OR14I1) with PC promotes endocytosis of virus particles, followed by gB activation by gH/gL/gO (or gH/gL) and final low-pH entry into the cell.

Human duodenal mucosal brush border Na+/H+ exchangers NHE2 and NHE3 alter net bicarbonate movement

2001 ◽  
Vol 281 (1) ◽  
pp. G159-G163 ◽  
Author(s):  
Maltin Repishti ◽  
Daniel L. Hogan ◽  
Vijaya Pratha ◽  
Laura Davydova ◽  
Mark Donowitz ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Brush Border ◽  
Polyclonal Antibodies ◽  
Duodenal Mucosa ◽  
Transport Processes ◽  
Apical Surface ◽  
Luminal Perfusion ◽  
Significant Step

The proximal duodenal mucosa secretes HCO[Formula: see text] that serves to protect the epithelium from injury. In isolated human duodenal enterocytes in vitro, multiple luminal membrane proteins are involved in acid/base transport. We postulated that one or more isoforms of the Na+/H+ exchanger (NHE) family is located on the apical surface of human duodenal mucosal epithelial cells and thereby contributes to duodenal mucosal HCO[Formula: see text] transport. Duodenal biopsies were obtained from human volunteers, and the presence of NHE2 and NHE3 was determined by using previously characterized polyclonal antibodies (Ab 597 for NHE2 and Ab 1381 for NHE3). In addition, proximal duodenal mucosal HCO[Formula: see text] transport was measured in humans in vivo in response to luminal perfusion of graded doses of amiloride; 10−5–10−4 M amiloride was used to inhibit NHE2 and 10−3 M amiloride to inhibit NHE3. Both NHE2 and NHE3 were localized principally to the brush border of duodenal villus cells. Sequential doses of amiloride resulted in significant, step-wise increases in net duodenal HCO[Formula: see text] output. Inhibition of NHE2 with 10−5 M and 10−4 M amiloride significantly increased net HCO[Formula: see text] output. Moreover, there was an additional, equivalent increase ( P < 0.05) in duodenal HCO[Formula: see text] output with 10−3 M amiloride, which inhibited NHE3. We conclude that 1) NHE2 and NHE3 are localized principally to the brush border of human duodenal villus epithelial cells; 2) sequential inhibition of NHE2 and NHE3 isoforms resulted in step-wise increases in net HCO[Formula: see text]output; 3) NHE2 and NHE3 participate in human duodenal villus cell HCO[Formula: see text] transport; and 4) the contribution of NHE-related transport events should be considered when studying duodenal HCO[Formula: see text] transport processes.

scholarly journals Hypoxia-Inducible Factor 1–Dependent Induction of Intestinal Trefoil Factor Protects Barrier Function during Hypoxia

2001 ◽  
Vol 193 (9) ◽  
pp. 1027-1034 ◽  
Author(s):  
Glenn T. Furuta ◽  
Jerrold R. Turner ◽  
Cormac T. Taylor ◽  
Robert M. Hershberg ◽  
Katrina Comerford ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Epithelial Cells ◽  
Barrier Function ◽  
Vascular Endothelial Cells ◽  
Hypoxia Inducible Factor ◽  
Trefoil Factor ◽  
Intestinal Trefoil Factor ◽  
Compensatory Mechanisms ◽  
Mobility Shift

Mucosal organs such as the intestine are supported by a rich and complex underlying vasculature. For this reason, the intestine, and particularly barrier-protective epithelial cells, are susceptible to damage related to diminished blood flow and concomitant tissue hypoxia. We sought to identify compensatory mechanisms that protect epithelial barrier during episodes of intestinal hypoxia. Initial studies examining T84 colonic epithelial cells revealed that barrier function is uniquely resistant to changes elicited by hypoxia. A search for intestinal-specific, barrier-protective factors revealed that the human intestinal trefoil factor (ITF) gene promoter bears a previously unappreciated binding site for hypoxia-inducible factor (HIF)-1. Hypoxia resulted in parallel induction of ITF mRNA and protein. Electrophoretic mobility shift assay analysis using ITF-specific, HIF-1 consensus motifs resulted in a hypoxia-inducible DNA binding activity, and loading cells with antisense oligonucleotides directed against the α chain of HIF-1 resulted in a loss of ITF hypoxia inducibility. Moreover, addition of anti-ITF antibody resulted in a loss of barrier function in epithelial cells exposed to hypoxia, and the addition of recombinant human ITF to vascular endothelial cells partially protected endothelial cells from hypoxia-elicited barrier disruption. Extensions of these studies in vivo revealed prominent hypoxia-elicited increases in intestinal permeability in ITF null mice. HIF-1–dependent induction of ITF may provide an adaptive link for maintenance of barrier function during hypoxia.

In vivo exposure to hyperoxia induces DNA damage in a population of alveolar type II epithelial cells

2004 ◽  
Vol 286 (5) ◽  
pp. L1045-L1054 ◽  
Author(s):  
Jason M. Roper ◽  
Dawn J. Mazzatti ◽  
Richard H. Watkins ◽  
William M. Maniscalco ◽  
Peter C. Keng ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Transmembrane Protein ◽  
Dna Integrity ◽  
Alveolar Type ◽  
Type I ◽  
Type Ii Cells ◽  
Type Ii ◽  
Alveolar Cells ◽  
Endogenous Expression

It is well established that hyperoxia injures and kills alveolar endothelial and type I epithelial cells of the lung. Although type II epithelial cells remain morphologically intact, it remains unclear whether they are also damaged. DNA integrity was investigated in adult mice whose type II cells were identified by their endogenous expression of pro-surfactant protein C or transgenic expression of enhanced green fluorescent protein. In mice exposed to room air, punctate perinuclear 8-oxoguanine staining was detected in ∼4% of all alveolar cells and in 30% of type II cells. After 48 or 72 h of hyperoxia, 8-oxoguanine was detected in 11% of all alveolar cells and in >60% of type II cells. 8-Oxoguanine colocalized by confocal microscopy with the mitochondrial transmembrane protein cytochrome oxidase subunit 1. Type II cells isolated from hyperoxic lungs exhibited nuclear DNA strand breaks by comet assay even though they were viable and morphologically indistinguishable from cells isolated from lungs exposed to room air. These data reveal that type II cells exposed to in vivo hyperoxia have oxidized and fragmented DNA. Because type II cells are essential for lung remodeling, our findings raise the possibility that they are proficient in DNA repair.

scholarly journals Humans surviving cholera develop antibodies against Vibrio cholerae O-specific polysaccharide that inhibit pathogen motility

2020 ◽  
Author(s):  
Richelle C. Charles ◽  
Meagan Kelly ◽  
Jenny M. Tam ◽  
Aklima Akter ◽  
Motaher Hossain ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Vibrio Cholerae ◽  
Polyclonal Antibody ◽  
High Speed ◽  
Polyclonal Antibodies ◽  
Intestinal Lumen ◽  
Dependent Manner ◽  
Specific Antibodies ◽  
Specific Polysaccharide

ABSTRACTThe mechanism of protection against cholera afforded by previous illness or vaccination is currently unknown. We have recently shown that antibodies targeting O-specific polysaccharide (OSP) of Vibrio cholerae correlate highly with protection against cholera. V. cholerae is highly motile and possesses a flagellum sheathed in O-specific polysaccharide (OSP), and motility of V. cholerae correlates with virulence. Using high speed video microscopy, and building upon previous animal-related work, we demonstrate that sera, polyclonal antibody fractions, and OSP-specific monoclonal antibodies recovered from humans surviving cholera block V. cholerae motility at both subagglutinating and agglutinating concentrations. This anti-motility effect is reversed by pre-adsorbing sera and polyclonal antibody fractions with purified OSP; and is associated with OSP-specific but not flagellin-specific monoclonal antibodies. F[ab] fragments of OSP-specific polyclonal antibodies do not inhibit motility, suggesting a requirement for antibody-mediated crosslinking in motility inhibition. We show that OSP-specific antibodies do not directly affect V. cholerae viability, but that OSP-specific monoclonal antibody highly protects against death in the murine cholera model. We used in vivo competitive index studies to demonstrate that OSP-specific antibodies impede colonization and survival of V. cholerae in intestinal tissues, and that this impact is motility-dependent. Our findings suggest that the impedance of motility by antibodies targeting V. cholerae OSP contributes to protection against cholera.IMPORTANCECholera is a severe dehydrating illness of humans caused by Vibrio cholerae. V. cholerae is a highly motile bacterium that has a single flagellum covered in lipopolysaccharide (LPS) displaying O-specific polysaccharide (OSP), and V. cholerae motility correlates with its ability to cause disease. The mechanisms of protection against cholera are not well understood; however, since V. cholerae is a non-invasive intestinal pathogen, it is likely that antibodies that bind the pathogen or its products in the intestinal lumen contribute to protection from infection. Here, we demonstrate that OSP-specific antibodies isolated from humans surviving cholera in Bangladesh inhibit V. cholerae motility and are associated with protection against challenge in a motility-dependent manner.

scholarly journals Brain Endothelial Cell TRPA1 Channels Initiate Neurovascular Coupling

2020 ◽  
Author(s):  
Pratish Thakore ◽  
Michael G. Alvarado ◽  
Sher Ali ◽  
Amreen Mughal ◽  
Paulo W. Pires ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Neuronal Activity ◽  
Transient Receptor Potential ◽  
Neurovascular Coupling ◽  
Laser Scanning Microscopy ◽  
K Channel ◽  
Transitional Region ◽  
Capillary Endothelial Cells ◽  
The Brain

Blood flow regulation in the brain is dynamically regulated to meet the metabolic demands of active neuronal populations. Recent evidence has demonstrated that capillary endothelial cells are essential mediators of neurovascular coupling that sense neuronal activity and generate a retrograde, propagating, hyperpolarizing signal that dilates upstream arterioles. Here, we tested the hypothesis that transient receptor potential ankyrin 1 (TRPA1) channels in capillary endothelial cells are significant contributors to functional hyperemic responses that underlie neurovascular coupling in the brain. Using an integrative ex vivo and in vivo approach, we demonstrate the functional presence of TRPA1 channels in brain capillary endothelial cells, and show that activation of these channels within the capillary bed, including the post-arteriole transitional region covered by ensheathing mural cells, initiates a retrograde signal that dilates upstream parenchymal arterioles. Notably, this signaling exhibits a unique biphasic mode of propagation that begins within the capillary network as a short-range, Ca2+ signal dependent on endothelial pannexin-1 channel/purinergic P2X receptor communication pathway and then is converted to a rapid, inward-rectifying K+ channel-mediated electrical signal in the post-arteriole transitional region that propagates upstream to parenchymal arterioles. Two-photon laser-scanning microscopy further demonstrated that conductive vasodilation occurs in vivo, and that TRPA1 is necessary for functional hyperemia within the somatosensory cortex of mice. Together, these data establish a role for endothelial TRPA1 channels as sensors of neuronal activity and show that they respond accordingly by initiating a vasodilatory response that redirects blood to regions of metabolic demand.

scholarly journals Endothelial expression of human APP leads to cerebral amyloid angiopathy in mice

2020 ◽  
Author(s):  
Yuriko Tachida ◽  
Saori Miura ◽  
Rie Imamaki ◽  
Naomi Ogasawara ◽  
Hiroyuki Takuwa ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Blood Vessels ◽  
Cerebral Amyloid Angiopathy ◽  
Amyloid Β ◽  
Blood Levels ◽  
Amyloid Angiopathy ◽  
Disease Mechanisms ◽  
Age Dependent ◽  
Cerebral Amyloid ◽  
The Brain

AbstractThe deposition of amyloid β (Aβ) in blood vessels of the brain, known as cerebral amyloid angiopathy (CAA), is observed in more than 90% of Alzheimer’s disease (AD) patients. The presence of such CAA pathology is not as evident, however, in most mouse models of AD, thereby making it difficult to examine the contribution of CAA to the pathogenesis of AD. Since blood levels of soluble amyloid precursor protein (sAPP) in rodents are less than 1% of those in humans, we hypothesized that endothelial APP expression would be markedly lower in rodents, thus providing a reason for the poorly expressed CAA pathology. Here we generated mice that specifically express human APP770 in endothelial cells. These mice exhibited an age-dependent robust deposition of Aβ in brain blood vessels but not in the parenchyma. Crossing these animals with APP knock-in mice led to an expanded CAA pathology as evidenced by increased amounts of amyloid accumulated in the cortical blood vessels. These results show that both neuronal and endothelial APP contribute cooperatively to vascular Aβ deposition, and suggest that this mouse model will be useful for studying disease mechanisms underlying CAA and for developing novel AD therapeutics.

scholarly journals Development and Application of Endothelial Cells Derived From Pluripotent Stem Cells in Microphysiological Systems Models

2021 ◽  
Vol 8 ◽  
Author(s):  
Crystal C. Kennedy ◽  
Erin E. Brown ◽  
Nadia O. Abutaleb ◽  
George A. Truskey
Keyword(s):  
Stem Cells ◽  
Endothelial Cells ◽  
Blood Vessels ◽  
Pluripotent Stem Cells ◽  
The Body ◽  
Organ Systems ◽  
Temporal Waveform ◽  
Induced Pluripotent

The vascular endothelium is present in all organs and blood vessels, facilitates the exchange of nutrients and waste throughout different organ systems in the body, and sets the tone for healthy vessel function. Mechanosensitive in nature, the endothelium responds to the magnitude and temporal waveform of shear stress in the vessels. Endothelial dysfunction can lead to atherosclerosis and other diseases. Modeling endothelial function and dysfunction in organ systems in vitro, such as the blood–brain barrier and tissue-engineered blood vessels, requires sourcing endothelial cells (ECs) for these biomedical engineering applications. It can be difficult to source primary, easily renewable ECs that possess the function or dysfunction in question. In contrast, human pluripotent stem cells (hPSCs) can be sourced from donors of interest and renewed almost indefinitely. In this review, we highlight how knowledge of vascular EC development in vivo is used to differentiate induced pluripotent stem cells (iPSC) into ECs. We then describe how iPSC-derived ECs are being used currently in in vitro models of organ function and disease and in vivo applications.

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