scholarly journals Vasculotide, an Angiopoietin-1 mimetic, reduces acute skin ionizing radiation damage in a preclinical mouse model

2021 ◽  
Author(s):  
Elina Korpela ◽  
Darren Yohan ◽  
Lee CL Chin ◽  
Anthony Kim ◽  
Xiaoyong Huang ◽  
...  

Background Most cancer patients are treated with radiotherapy, but the treatment can also damage the surrounding normal tissue. Acute skin damage from cancer radiotherapy diminishes patients’ quality of life, yet effective biological interventions for this damage are lacking. Protecting microvascular endothelial cells from irradiation-induced perturbations is emerging as a targeted damage-reduction strategy. Since Angiopoetin-1 signaling through the Tie2 receptor on endothelial cells opposes microvascular perturbations in other disease contexts, we used a preclinical Angiopoietin-1 mimic called Vasculotide to investigate its effect on skin radiation toxicity using a preclinical model. Methods Athymic mice were treated intraperitoneally with saline or Vasculotide and their flank skin was irradiated with a single large dose of ionizing radiation. Acute cutaneous damage and wound healing were evaluated by clinical skin grading, histology and immunostaining. Diffuse reflectance optical spectroscopy, myeloperoxidase-dependent bioluminescence imaging of neutrophils and a serum cytokine array were used to assess inflammation. Microvascular endothelial cell response to radiation was tested with in vitro clonogenic and Matrigel tubule formation assays. Tumour xenograft growth delay experiments were also performed. Appreciable differences between treatment groups were assessed mainly using parametric and non-parametric statistical tests comparing areas under curves, followed by post-hoc comparisons. Results In vivo, different schedules of Vasculotide treatment reduced the size of the irradiation-induced wound. Although skin damage scores remained similar on individual days, Vasculotide administered post irradiation resulted in less skin damage overall. Vasculotide alleviated irradiation-induced inflammation in the form of reduced levels of oxygenated hemoglobin, myeloperoxidase bioluminescence and chemokine MIP-2. Surprisingly, Vasculotide-treated animals also had higher microvascular endothelial cell density in wound granulation tissue. In vitro, Vasculotide enhanced the survival and function of irradiated endothelial cells. Conclusions Vasculotide administration reduces acute skin radiation damage in mice, and may do so by affecting several biological processes. This radiation protection approach may have clinical impact for cancer radiotherapy patients by reducing the severity of their acute skin radiation damage.

2021 ◽  
Author(s):  
Elina Korpela ◽  
Darren Yohan ◽  
Lee CL Chin ◽  
Anthony Kim ◽  
Xiaoyong Huang ◽  
...  

Background Most cancer patients are treated with radiotherapy, but the treatment can also damage the surrounding normal tissue. Acute skin damage from cancer radiotherapy diminishes patients’ quality of life, yet effective biological interventions for this damage are lacking. Protecting microvascular endothelial cells from irradiation-induced perturbations is emerging as a targeted damage-reduction strategy. Since Angiopoetin-1 signaling through the Tie2 receptor on endothelial cells opposes microvascular perturbations in other disease contexts, we used a preclinical Angiopoietin-1 mimic called Vasculotide to investigate its effect on skin radiation toxicity using a preclinical model. Methods Athymic mice were treated intraperitoneally with saline or Vasculotide and their flank skin was irradiated with a single large dose of ionizing radiation. Acute cutaneous damage and wound healing were evaluated by clinical skin grading, histology and immunostaining. Diffuse reflectance optical spectroscopy, myeloperoxidase-dependent bioluminescence imaging of neutrophils and a serum cytokine array were used to assess inflammation. Microvascular endothelial cell response to radiation was tested with in vitro clonogenic and Matrigel tubule formation assays. Tumour xenograft growth delay experiments were also performed. Appreciable differences between treatment groups were assessed mainly using parametric and non-parametric statistical tests comparing areas under curves, followed by post-hoc comparisons. Results In vivo, different schedules of Vasculotide treatment reduced the size of the irradiation-induced wound. Although skin damage scores remained similar on individual days, Vasculotide administered post irradiation resulted in less skin damage overall. Vasculotide alleviated irradiation-induced inflammation in the form of reduced levels of oxygenated hemoglobin, myeloperoxidase bioluminescence and chemokine MIP-2. Surprisingly, Vasculotide-treated animals also had higher microvascular endothelial cell density in wound granulation tissue. In vitro, Vasculotide enhanced the survival and function of irradiated endothelial cells. Conclusions Vasculotide administration reduces acute skin radiation damage in mice, and may do so by affecting several biological processes. This radiation protection approach may have clinical impact for cancer radiotherapy patients by reducing the severity of their acute skin radiation damage.


2020 ◽  
Vol 21 (15) ◽  
pp. 5249 ◽  
Author(s):  
Anne-Claire Lagrée ◽  
Fabienne Fasani ◽  
Clotilde Rouxel ◽  
Marine Pivet ◽  
Marie Pourcelot ◽  
...  

Microvascular endothelial cells constitute potential targets for exogenous microorganisms, in particular for vector-borne pathogens. Their phenotypic and functional variations according to the organs they are coming from provide an explanation of the organ selectivity expressed in vivo by pathogens. In order to make available relevant tools for in vitro studies of infection mechanisms, our aim was to immortalize bovine organospecific endothelial cells but also to assess their permissivity to viral infection. Using transfection with SV40 large T antigen, six bovine microvascular endothelial cell lines from various organs and one macrovascular cell line from an umbilical cord were established. They display their own panel of endothelial progenitor/mature markers, as assessed by flow cytometry and RT-qPCR, as well as the typical angiogenesis capacity. Using both Bluetongue and foot-and-mouth disease viruses, we demonstrate that some cell lines are preferentially infected. In addition, they can be transfected and are able to express viral proteins such as BTV8-NS3. Such microvascular endothelial cell lines bring innovative tools for in vitro studies of infection by viruses or bacteria, allowing for the study of host-pathogen interaction mechanisms with the actual in vivo target cells. They are also suitable for applications linked to microvascularization, such as anti-angiogenic and anti-tumor research, growing fields in veterinary medicine.


Blood ◽  
1991 ◽  
Vol 77 (2) ◽  
pp. 294-305
Author(s):  
DH Robinson ◽  
MK Warren ◽  
LT Liang ◽  
JJ Oprandy ◽  
TB Nielsen ◽  
...  

We report that L-cell-conditioned medium (LCM) transforms porcine cerebral microvascular (PCMV) endothelial cells into cells with macrophage-like properties. LCM is known to contain both cytokine(s) and the L-cell virus, a murine retrovirus found in the L929 cell and LCM. Our evidence suggests that both LCM cytokine(s) and the L-cell virus are involved in this PCMV endothelial cell transformation. Criteria for transformation include focus formation, decreased serum requirements for growth, changes in morphology including nonadherence, propagation in suspension culture, and a decreased growth response to stimulation with a known endothelial cell mitogen. Macrophage-like characteristics of this transformed cell, designated as RVTE, include pinocytosis of low-density lipoprotein, Fc receptor-mediated phagocytosis, phagocytosis of bacteria and zymosan, the expression of macrophage enzyme markers, and constitutive production of colony- stimulating factor 1. However, the transformed cell retains several properties of the nontransformed cell including the expression of FVIII:RAg and in vitro self-organization into capillary-like structures. Cloning of RVTE cells clearly shows that both macrophage- like and cerebral microvascular endothelial cell properties are present in the same cell. During self-organization, nontransformed cells express morphologic and functional characteristics classically associated with the macrophage. These findings suggest that some brain capillary pathophysiologies could involve macrophage-like cerebral microvascular endothelial cells. Furthermore, the “reticuloendothelial” phenotypic repertoire expressed by this transformed cerebral microvascular endothelial cell may show that the cerebral capillary endothelial cell in vivo is derived from a hematopoietic and/or phagocytic precursor.


Blood ◽  
1991 ◽  
Vol 77 (2) ◽  
pp. 294-305 ◽  
Author(s):  
DH Robinson ◽  
MK Warren ◽  
LT Liang ◽  
JJ Oprandy ◽  
TB Nielsen ◽  
...  

Abstract We report that L-cell-conditioned medium (LCM) transforms porcine cerebral microvascular (PCMV) endothelial cells into cells with macrophage-like properties. LCM is known to contain both cytokine(s) and the L-cell virus, a murine retrovirus found in the L929 cell and LCM. Our evidence suggests that both LCM cytokine(s) and the L-cell virus are involved in this PCMV endothelial cell transformation. Criteria for transformation include focus formation, decreased serum requirements for growth, changes in morphology including nonadherence, propagation in suspension culture, and a decreased growth response to stimulation with a known endothelial cell mitogen. Macrophage-like characteristics of this transformed cell, designated as RVTE, include pinocytosis of low-density lipoprotein, Fc receptor-mediated phagocytosis, phagocytosis of bacteria and zymosan, the expression of macrophage enzyme markers, and constitutive production of colony- stimulating factor 1. However, the transformed cell retains several properties of the nontransformed cell including the expression of FVIII:RAg and in vitro self-organization into capillary-like structures. Cloning of RVTE cells clearly shows that both macrophage- like and cerebral microvascular endothelial cell properties are present in the same cell. During self-organization, nontransformed cells express morphologic and functional characteristics classically associated with the macrophage. These findings suggest that some brain capillary pathophysiologies could involve macrophage-like cerebral microvascular endothelial cells. Furthermore, the “reticuloendothelial” phenotypic repertoire expressed by this transformed cerebral microvascular endothelial cell may show that the cerebral capillary endothelial cell in vivo is derived from a hematopoietic and/or phagocytic precursor.


2019 ◽  
Vol 20 (20) ◽  
pp. 5227 ◽  
Author(s):  
Anjana Ajikumar ◽  
Merete B. Long ◽  
Paul R. Heath ◽  
Stephen B. Wharton ◽  
Paul G. Ince ◽  
...  

The blood-brain barrier (BBB), composed of brain microvascular endothelial cells (BMEC) that are tightly linked by tight junction (TJ) proteins, restricts the movement of molecules between the periphery and the central nervous system. Elevated systemic levels of neutrophils have been detected in patients with altered BBB function, but the role of neutrophils in BMEC dysfunction is unknown. Neutrophils are key players of the immune response and, when activated, produce neutrophil-derived microvesicles (NMV). NMV have been shown to impact the integrity of endothelial cells throughout the body and we hypothesize that NMV released from circulating neutrophils interact with BMEC and induce endothelial cell dysfunction. Therefore, the current study investigated the interaction of NMV with human BMEC and determined whether they altered gene expression and function in vitro. Using flow cytometry and confocal imaging, NMV were shown to be internalized by the human cerebral microvascular endothelial cell line hCMEC/D3 via a variety of energy-dependent mechanisms, including endocytosis and macropinocytosis. The internalization of NMV significantly altered the transcriptomic profile of hCMEC/D3, specifically inducing the dysregulation of genes associated with TJ, ubiquitin-mediated proteolysis and vesicular transport. Functional studies confirmed NMV significantly increased permeability and decreased the transendothelial electrical resistance (TEER) of a confluent monolayer of hCMEC/D3. These findings indicate that NMV interact with and affect gene expression of BMEC as well as impacting their integrity. We conclude that NMV may play an important role in modulating the permeability of BBB during an infection.


1992 ◽  
Vol 1 (4) ◽  
pp. 293-298 ◽  
Author(s):  
Carlton Young ◽  
Bruce E. Jarrell ◽  
James B. Hoying ◽  
Stuart K. Williams

The transplantation of endothelial cells represents a technology which has been suggested for applications ranging from improvement in function of implanted vascular devices to genetic therapy. The use of microvascular endothelial cell transplantation has seen increased use both in animal studies as well as clinical use. This report describes our techniques for the isolation and establishment of initial cultures of microvascular endothelial cells derived from porcine fat. A variety of anatomic sites within the pig were evaluated to determine the appropriateness of different sources of fat for endothelial cell isolation. The properitoneal fat was determined to be optimal due to the predominance of endothelium in this tissue and the ease of isolation of microvascular endothelium following collagenase digestion. The study of endothelial cell transplantation in the porcine model is now possible using the methods described for adipose tissue-derived micro vessel endothelial cell isolation.


1993 ◽  
Vol 264 (2) ◽  
pp. H639-H652 ◽  
Author(s):  
M. Nishida ◽  
W. W. Carley ◽  
M. E. Gerritsen ◽  
O. Ellingsen ◽  
R. A. Kelly ◽  
...  

Although reciprocal intercellular signaling may occur between endocardial or microvascular endothelium and cardiac myocytes, suitable in vitro models have not been well characterized. In this report, we describe the isolation and primary culture of cardiac microvascular endothelial cells (CMEC) from both adult rat and human ventricular tissue. Differential uptake of fluorescently labeled acetylated low-density lipoprotein (Ac-LDL) indicated that primary isolates of rat CMEC were quite homogeneous, unlike primary isolates of human ventricular tissue, which required cell sorting based on Ac-LDL uptake to create endothelial cell-enriched primary cultures. The endothelial phenotype of both primary isolates and postsort subcultured CMEC and their microvascular origin were determined by characteristic histochemical staining for a number of endothelial cell-specific markers, by the absence of cells with fibroblast or pericyte-specific cell surface antigens, and by rapid tube formation on purified basement membrane preparations. Importantly, [3H]-thymidine uptake was increased 2.3-fold in subconfluent rat microvascular endothelial cells 3 days after coculture with adult rat ventricular myocytes because of release of an endothelial cell mitogen(s) into the extracellular matrix, resulting in a 68% increase in cell number compared with CMEC in monoculture. Thus biologically relevant cell-to-cell interactions can be modeled with this in vitro system.


1986 ◽  
Vol 250 (6) ◽  
pp. C970-C977 ◽  
Author(s):  
R. M. Rosenbaum ◽  
C. D. Cheli ◽  
M. E. Gerritsen

The effects of dexamethasone on prostaglandin secretion by cultivated rabbit coronary microvascular endothelial (RCME) cells were investigated. Incubation of RCME cells with dexamethasone resulted in a time- and concentration-dependent decrease in prostaglandin accumulation in the culture media and reduced basal and A23187-stimulated prostaglandin (PG) E2 and 6-keto-PGF1 alpha release. The maximal effects of dexamethasone (50-80% inhibition) were achieved after 16-18 h of incubation with the steroid at a final concentration of 10(-7) M. The effects of dexamethasone treatment were partially reversed 24 h after removal of the steroid from the culture media. Dexamethasone treatment did not reduce arachidonic acid-stimulated prostaglandin synthesis, indicating that the level of inhibition was proximal to that of cyclooxygenase. The inhibitory effects of dexamethasone could be prevented by pretreatment of the RCME cells with actinomycin D or cycloheximide, suggesting a requirement for protein synthesis in the inhibitory action of dexamethasone. Conditioned media from dexamethasone-treated cells contained a factor that inhibited porcine pancreatic phospholipase A2 (PLA2) in vitro. Transfer of conditioned media from dexamethasone-treated cells to untreated cells did not reduce basal or stimulated prostaglandin release; in contrast, a stimulatory action was consistently observed. Adherence of rabbit peripheral polymorphonuclear leukocytes (PMN) to RCME cells was reduced when the leukocytes were pretreated with 10(-7) M dexamethasone (4 h). However, dexamethasone pretreatment of the RCME cells did not significantly effect granulocyte adhesion. Thus coronary microvascular endothelial cell prostaglandin production is regulated by glucocorticoids, and glucocorticoid-pretreated microvascular endothelial cell release an inhibitor of PLA2 activity into the culture media.(ABSTRACT TRUNCATED AT 250 WORDS)


2013 ◽  
Vol 183 (2) ◽  
pp. 604-616 ◽  
Author(s):  
Rebecca R. Foster ◽  
Lynne Armstrong ◽  
Siân Baker ◽  
Dickson W.L. Wong ◽  
Emma C. Wylie ◽  
...  

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