Allogeneic Antigen Composition for Preparing Universal Cancer Vaccines

Recently it was demonstrated that tumors induce specific changes to the surface of human endothelial cells thereby providing the basis for designing endothelial cell-based vaccines that directly target antigens expressed by the tumor endothelium. The present report extends these studiesin vitroby investigating the efficacy of allogeneic antigens with regard to their ability to target immune responses against the tumor vasculature since alloantigens simplify vaccine development and implementation in clinical practice. We demonstrated that allogeneic SANTAVAC (Set of All Natural Target Antigens for Vaccination Against Cancer), which presents a specifically prepared composition of cell surface antigens from tumor-stimulated endothelial cells, allows targeting of the tumor vasculature with efficacy of 17, where efficacy represents the killing rate of target cells before normal cells are adversely affected, and efficacy of 60, where efficacy represents the fold decrease in the number of target cells and directly relates to tumor growth arrest. These data suggest that allogeneic SANTAVAC may be considered an antigenic composition that following administration in the presence of respective adjuvants may be clinically tested as a therapeutic or prophylactic universal cancer vaccine without adverse side effects to the normal vasculature.

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Incorporation of Tumor Vasculature Targeting Motifs into Moloney Murine Leukemia Virus Env Escort Proteins Enhances Retrovirus Binding and Transduction of Human Endothelial Cells

Journal of Virology ◽

10.1128/jvi.74.11.5320-5328.2000 ◽

2000 ◽

Vol 74 (11) ◽

pp. 5320-5328 ◽

Cited By ~ 30

Author(s):

Liqiong Liu ◽

Ling Liu ◽

W. French Anderson ◽

Robert W. Beart ◽

Erlinda M. Gordon ◽

...

Keyword(s):

Endothelial Cells ◽

Endothelial Cell ◽

Tumor Vasculature ◽

Retroviral Vectors ◽

Transduction Efficiency ◽

Target Cells ◽

Binding Motif ◽

Cell Binding ◽

Human Endothelial Cells ◽

Murine Leukemia

ABSTRACT Adhesion receptors expressed on the surfaces of tumor-activated endothelial cells provide an advantageous locus for targeting gene therapy vectors to angiogenic tissues and/or tumor vasculature. In this study, we engineered a series of Asn-Gly-Arg (NGR)-containing congeners of the presumptive cell binding motif contained within the ninth type III repeat of fibronectin and displayed these tumor vasculature targeting motifs (TVTMs) within the context of Moloney murine leukemia envelope “escort” proteins. Comparative studies of envelope incorporation into viral particles and evaluation of the cell binding properties of the targeted vectors revealed critical structural features, thus identifying a subset of optimal TVTMs. Utilizing a modified ELISA to evaluate viral binding to target cells, we observed a significant down-regulation of TVTM-virion binding to human endothelial cells following sustained (48-h) exposure to VEGF. Normalized for equivalent titers (106 CFU/ml), as assayed on NIH 3T3 cells, vectors displaying TVTM escort proteins significantly enhanced the transduction efficiency from 12.2 to 37.4% in human KSY-1 endothelial cell cultures (P < 0.001) and from 0.4 to 4.1% in human umbilical vein endothelial cell (HUVEC) cultures (P < 0.001). In summary, these studies utilized an engineering approach to identify a subset of TVTMs that are stably incorporated as envelope “escort” proteins into retroviral vectors and that, by functioning to improve the binding efficiency and transduction of both HUVEC and KSY1 endothelial cells, may have therapeutic potential for targeting gene delivery to the tumor-associated vasculature.

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Serum Derived Extracellular Vesicles Mediated Delivery of Synthetic miRNAs in Human Endothelial Cells

Frontiers in Molecular Biosciences ◽

10.3389/fmolb.2021.636587 ◽

2021 ◽

Vol 8 ◽

Author(s):

Marta Tapparo ◽

Margherita Alba Carlotta Pomatto ◽

Maria Chiara Deregibus ◽

Elli Papadimitriou ◽

Claudia Cavallari ◽

...

Keyword(s):

Endothelial Cells ◽

Extracellular Vesicles ◽

Rna Binding ◽

Cell Communication ◽

Bioactive Molecules ◽

Target Cells ◽

Human Endothelial Cells ◽

Synthetic Mirnas

Extracellular vesicles (EVs) have emerged in the last decades as a cell-to-cell communication mechanism. One of their mechanism of action is the direct delivery of their cargo, composed of bioactive molecules to target cells. Different methods (direct electroporation, cell transfection, chemical transfection) were developed to vehicle therapeutic molecules through EVs. However, most of these techniques presented some limitations such as EV disruption and aggregation. In the present study, we demonstrated that a direct temperature-controlled co-incubation of EVs with defined miRNAs is a stable method to deliver information to target cells without affecting EV constitutive content. We chose serum as an easy and abundant source of EVs applicable to autologous treatment after EV modification. Exogenous cel-miR-39 loaded on serum EVs (SEVs) was taken up by human endothelial cells, demonstrating an adequate miRNA loading efficacy based on the co-incubation method. Moreover, SEVs co-incubation with the angiomiRNA-126 (miR-126) enhanced their angiogenic properties in vitro and in vivo by increasing the capacity to induce capillary-like structure formation of human endothelial cells. MiR-126 loaded EVs were also shown to stimulate mouse endothelial cells to invade Matrigel plugs and create more vessels with respect to the EV naive counterpart. When SEVs were loaded with miR-19b, an anti-angiogenic miRNA, they were able to reduce Vascular endothelial growth factors (VEGF) pro-angiogenic capacity, supporting the selective biological effect mediated by the carried miRNA. Lastly, we identified Annexin A2 (ANXA2) as one of the molecules involved in the exogenous RNA binding to serum EV surface, favoring miRNA delivery to target endothelial cells for potential therapeutic application.

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Acute damage to human endothelial cells by brief exposure to contrast media in vitro.

Radiology ◽

10.1148/radiology.147.3.6844604 ◽

1983 ◽

Vol 147 (3) ◽

pp. 681-684 ◽

Cited By ~ 50

Author(s):

F Laerum

Keyword(s):

Endothelial Cells ◽

Contrast Media ◽

Human Endothelial Cells

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Vascular repair utilising immobilised heparin conjugate for protection against early activation of inflammation and coagulation

Thrombosis and Haemostasis ◽

10.1160/th14-09-0724 ◽

2015 ◽

Vol 113 (06) ◽

pp. 1312-1322 ◽

Cited By ~ 18

Author(s):

Sofia Nordling ◽

Jaan Hong ◽

Karin Fromell ◽

Fredrik Edin ◽

Johan Brännström ◽

...

Keyword(s):

Endothelial Cells ◽

Thrombus Formation ◽

Innate Immune ◽

Human Endothelial Cells ◽

Coagulation Activation ◽

Ischaemia Reperfusion Injury ◽

Novel Approach ◽

One Step ◽

Chamber Model

SummaryIschaemia-reperfusion injury (IRI) poses a major challenge in many thrombotic conditions and in whole organ transplantation. Activation of the endothelial cells and shedding of the protective vascular glycocalyx during IRI increase the risk of innate immune activation, cell infiltration and severe thrombus formation, promoting damage to the tissue. Here, we present a novel one-step strategy to protect the vasculature by immobilisation of a unique multi-arm heparin conjugate to the endothelium. Applying a new in vitro blood endothelial cell chamber model, the heparin conjugate was found to bind not only to primary human endothelial cells but also directly to the collagen to which the cells adhered. Incubation of hypoxic endothelial cells with freshly drawn human blood in the blood chambers elicited coagulation activation reflected by thrombin anti-thrombin formation and binding of platelets and neutrophils. Immobilisation of the heparin conjugate to the hypoxic endothelial cells created a protective coating, leading to a significant reduction of the recruitment of blood cells and coagulation activation compared to untreated hypoxic endothelial cells. This novel approach of immobilising multi-arm heparin conjugates on the endothelial cells and collagen of the basement membrane ensures to protect the endothelium against IRI in thrombotic disorders and in transplantation.

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Centrifugal enhancement of Kaposi's sarcoma-associated virus infection of human endothelial cells in vitro

Journal of Virological Methods ◽

10.1016/j.jviromet.2008.07.026 ◽

2008 ◽

Vol 154 (1-2) ◽

pp. 160-166 ◽

Cited By ~ 24

Author(s):

Seung-Min Yoo ◽

Ae-Kyung Ahn ◽

Taegun Seo ◽

Hyo Bong Hong ◽

Myung-Ae Chung ◽

...

Keyword(s):

Endothelial Cells ◽

Virus Infection ◽

Kaposi's Sarcoma ◽

Kaposi’S Sarcoma ◽

Human Endothelial Cells

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Caspase Activation Is Required for Nitric Oxide–Mediated, CD95(APO-1/Fas)–Dependent and Independent Apoptosis in Human Neoplastic Lymphoid Cells

Blood ◽

10.1182/blood.v91.11.4311 ◽

1998 ◽

Vol 91 (11) ◽

pp. 4311-4320 ◽

Cited By ~ 57

Author(s):

Katerina Chlichlia ◽

Marcus E. Peter ◽

Marian Rocha ◽

Carsten Scaffidi ◽

Mariana Bucur ◽

...

Keyword(s):

Nitric Oxide ◽

Present Report ◽

Lymphoid Cells ◽

Jurkat Cells ◽

Target Cells ◽

No Production ◽

No Donor ◽

Synthase Inhibitor ◽

Inhibitor Of Protein Synthesis

Abstract Nitric oxide (NO), an important effector molecule involved in immune regulation and host defense, was shown to induce apoptosis in lymphoma cells. In the present report the NO donor glycerol trinitrate was found to induce apoptosis in Jurkat cells that are sensitive to CD95-mediated kill. In contrast, a CD95-resistant Jurkat subclone showed substantial protection from apoptosis after exposure to NO. NO induced mRNA expression of CD95 (APO-1/Fas) and TRAIL/APO-2 ligands. Moreover, NO triggered apoptosis in freshly isolated human leukemic lymphocytes which were also sensitive to anti-CD95 treatment. The ability of NO to induce apoptosis was completely blocked by a broad-spectrum ICE (interleukin-1β converting enzyme)-protease/caspase inhibitor and correlated with FLICE/caspase-8 activation. This activation was abrogated in some neoplastic lymphoid cells but not in others by the inhibitor of protein synthesis cycloheximide. Our results were confirmed using an in vitro experimental model of coculture of human lymphoid target cells with activated bovine endothelial cells generating NO as effectors. Furthermore, the inhibition of endogenous NO production with the inducible NO synthase inhibitor NG-monomethyl-L-arginine caused a complete abrogation of the apoptotic effect. Our data provide evidence that NO-induced apoptosis in human neoplastic lymphoid cells strictly requires activation of caspases, in particular FLICE, the most CD95 receptor-proximal caspase. Depending on the cell line tested this activation required or was independent of the CD95 receptor/ligand system.

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