739 research outputs found
Targeting fibroblast activation protein in tumor stroma with chimeric antigen receptor T cells can inhibit tumor growth and augment host immunity without severe toxicity.
The majority of chimeric antigen receptor (CAR) T-cell research has focused on attacking cancer cells. Here, we show that targeting the tumor-promoting, nontransformed stromal cells using CAR T cells may offer several advantages. We developed a retroviral CAR construct specific for the mouse fibroblast activation protein (FAP), comprising a single-chain Fv FAP [monoclonal antibody (mAb) 73.3] with the CD8α hinge and transmembrane regions, and the human CD3ζ and 4-1BB activation domains. The transduced muFAP-CAR mouse T cells secreted IFN-γ and killed FAP-expressing 3T3 target cells specifically. Adoptively transferred 73.3-FAP-CAR mouse T cells selectively reduced FAP(hi) stromal cells and inhibited the growth of multiple types of subcutaneously transplanted tumors in wild-type, but not FAP-null immune-competent syngeneic mice. The antitumor effects could be augmented by multiple injections of the CAR T cells, by using CAR T cells with a deficiency in diacylglycerol kinase, or by combination with a vaccine. A major mechanism of action of the muFAP-CAR T cells was the augmentation of the endogenous CD8(+) T-cell antitumor responses. Off-tumor toxicity in our models was minimal following muFAP-CAR T-cell therapy. In summary, inhibiting tumor growth by targeting tumor stroma with adoptively transferred CAR T cells directed to FAP can be safe and effective, suggesting that further clinical development of anti-human FAP-CAR is warranted
An anti-platelet-endothelial cell adhesion molecule-1 antibody inhibits leukocyte extravasation from mesenteric microvessels in vivo by blocking the passage through the basement membrane
Openings and closings in Spanish email conversations
Despite the increasing interest scholarly research has shown in the study of computer-mediated communication, there is still a need to investigate the empirical validity of assumed homogeneity of language usage over the net and focus on the social diversity and variation that characterizes any communication. With this in mind, the present paper is an investigation into the stylistic choices that a particular group of email users made when engaged in a specific activity type. More specifically, it explores the variation in the discourse practices employed to open and close emails in conversation alongside the institutional power of participants and the interactional position of each email contributing to the conversation. To carry out this study a corpus of short email conversations in Peninsular Spanish was collected (n = 240). The analysis focused on the opening and closing sequences of the emails that made up the conversations and considered opening and closing linguistic conventions as discursive practices that members of a community may use strategically. The findings revealed that the discursive practices under scrutiny were subject not only to technological but also to social and interactional constraints and thus highlighted contextual variability. Further, the high degree of sociability in the electronic episodes studied was interpreted as reflecting a ¿people first, business second¿ communicative style
The effect of starch-based biomaterials on leukocyte adhesion and activation in vitro
Leukocyte adhesion to biomaterials has long been recognised as a key element to
determine their inflammatory potential. Results regarding leukocyte adhesion and
activation are contradictory in some aspects of the material’s effect in determining these
events. It is clear that together with the wettability or hydrophilicity/hydrophobicity, the
roughness of a substrate has a major effect on leukocyte adhesion. Both the chemical and
physical properties of a material influence the adsorbed proteins layer which in turn
determines the adhesion of cells.
In this work polymorphonuclear (PMN) cells and a mixed population of
monocytes/macrophages and lymphocytes (mononuclear cells) were cultured separately
with a range of starch-based materials and composites with hydroxyapatite (HA). A
combination of both reflected light microscopy and scanning electron microscopy (SEM)
was used in order to study the leukocyte morphology. The quantification of the enzyme
lactate dehydrogenase (LDH) was used to determine the number of viable cells adhered to
the polymers. Cell adhesion and activation was characterised by immunocytochemistry
based on the expression of several adhesion molecules, crucial in the progress of an
inflammatory response.
This work supports previous in vitro studies with PMN and monocytes/macrophages,
which demonstrated that there are several properties of the materials that can influence
and determine their biological response. From our study, monocytes/macrophages and
lymphocytes adhere in similar amounts to more hydrophobic (SPCL) and to moderately
hydrophilic (SEVA-C) surfaces and do not preferentially adhere to rougher substrates
(SCA). Contrarily, more hydrophilic surfaces (SCA) induced higher PMN adhesion and
lower activation. In addition, the hydroxyapatite reinforcement induces changes in cell
behaviour for some materials but not for others.
The observed response to starch-based biodegradable polymers was not significantly
different from the control materials. Thus, the results reported herein indicate the low
potential of the starch-based biodegradable polymers to induce inflammation especially
the HA reinforced composite materials
Strategies to inhibit tumour associated integrin receptors: rationale for dual and multi-antagonists
YesThe integrins are a family of 24 heterodimeric transmembrane cell surface receptors. Involvement in cell attachment to the extracellular matrix, motility, and proliferation identifies integrins as therapeutic targets in cancer and associated conditions; thrombosis, angiogenesis and osteoporosis. The most reported strategy for drug development is synthesis of an agent that is highly selective for a single integrin receptor. However, the ability of cancer cells to change their integrin repertoire in response to drug treatment renders this approach vulnerable to the development of resistance and paradoxical promotion of tumor growth. Here, we review progress towards development of antagonists targeting two or more members of the RGD-binding integrins, notably αvβ3, αvβ5, αvβ6, αvβ8, α5β1, and αIIbβ3, as anticancer therapeutics
Photopatterned antibodies for selective cell attachment
We present a phototriggerable system that allows for the spatiotemporal controlled attachment of selected cell types to a biomaterial using immobilized antibodies that specifically target individual cell phenotypes.o-Nitrobenzyl caged biotin was used to functionalize chitosan membranes and mediate site-specific coupling of streptavidin and biotinylated antibodies after light activation. The ability of this system to capture and immobilize specific cells on a surface was tested using endothelial-specific biotinylated antibodies and nonspecific ones as controls. Homogeneous patterned monolayers of human umbilical vein endothelial cells were obtained on CD31-functionalized surfaces. This is a simple and generic approach that is applicable to other ligands, materials, and cell types and shows the flexibility of caged ligands to trigger and control the interaction between cells and biomaterials.We thank Martina Knecht (MPIP) for help with the synthesis of caged biotin and Dr. Ron Unger and Prof. C. J. Kirkpatrick (University Clinic Mainz, RepairLab) for providing HUVECs. C.A.C. acknowledges funding support from the Portuguese Foundation for Science and Technology (FCT) (fellowship SFRH/BD/61390/2009) and from the International Max-Planck Research School in Mainz. The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement no. REGPOT-CT2012-316331-POLARIS
Влияние фосфатных связующих на физико-механические свойства периклазохромитовых огнеупоров
У данній статті наведено та порівняно фізико-механічні властивості периклазо-хромітових матеріалів в залежності від різних типів фосфатних зв’язуючих та введення різних домішок. Визначено, що найбільш раціональним є введення триполіфосфату натрію.In given clause are resulted and the physycal-mechanical properties periclase-cgromite of materials are compared depending on different of types phosphate binding and introduction of the various additives. Is determined, that most rational is the introduction treepolyphosphate sodume
Platelet endothelial cell adhesion molecule-1 in neutrophil emigration during acute bacterial pneumonia in mice and rats
Platelet endothelial cell adhesion molecule-1 (PECAM-1) (CD31) is an adhesion molecule believed to mediate transendothelial migration of neutrophils and other leukocytes after CD11/CD18-mediated adhesion. Our study evaluated the role of PECAM-1 in neutrophil emigration across the pulmonary capillaries and the bronchial microvasculature using blocking anti-PECAM-1 antibodies in mice and rats. Neutrophil emigration was induced by Escherichia coli, a stimulus eliciting CD11/CD18-dependent emigration, or Streptococcus pneumoniae, a stimulus inducing CD11/CD18-independent emigration. Although anti-PECAM-1 antibodies partially inhibited glycogen-induced neutrophil emigration into the peritoneum, neutrophil emigration across either the pulmonary capillaries or the bronchial microvasculature in response to either E. coli or S. pneumoniae was not prevented when the function of PECAM-1 was inhibited in either mice or rats. There was also no increase in the number of intravascular neutrophils within the bronchial vessels after treatment with anti-PECAM-1 antibody. These studies indicate that either CD11/CD18-dependent or -independent adhesion pathways may lead to PECAM-1-independent transendothelial migration through the pulmonary or the bronchial endothelium
The effect of an external magnetic force on cell adhesion and proliferation of magnetically labeled mesenchymal stem cells
<p>Abstract</p> <p>Background</p> <p>As the strategy for tissue regeneration using mesenchymal stem cells (MSCs) for transplantation, it is necessary that MSCs be accumulated and kept in the target area. To accumulate MSCs effectively, we developed a novel technique for a magnetic targeting system with magnetically labeled MSCs and an external magnetic force. In this study, we examined the effect of an external magnetic force on magnetically labeled MSCs in terms of cell adhesion and proliferation.</p> <p>Methods</p> <p>Magnetically labeled MSCs were plated at the bottom of an insert under the influence of an external magnetic force for 1 hour. Then the inserts were turned upside down for between 1 and 24 hours, and the number of MSCs which had fallen from the membrane was counted. The gene expression of MSCs affected magnetic force was analyzed with microarray. In the control group, the same procedure was done without the external magnetic force.</p> <p>Results</p> <p>At 1 hour after the inserts were turned upside down, the average number of fallen MSCs in the magnetic group was significantly smaller than that in the control group, indicating enhanced cell adhesion. At 24 hours, the average number of fallen MSCs in the magnetic group was also significantly smaller than that in control group. In the magnetic group, integrin alpha2, alpha6, beta3 BP, intercellular adhesion molecule-2 (ICAM-2), platelet/endothelial cell adhesion molecule-1 (PECAM-1) were upregulated. At 1, 2 and 3 weeks after incubation, there was no statistical significant difference in the numbers of MSCs in the magnetic group and control group.</p> <p>Conclusions</p> <p>The results indicate that an external magnetic force for 1 hour enhances cell adhesion of MSCs. Moreover, there is no difference in cell proliferation after using an external magnetic force on magnetically labeled MSCs.</p
Involvement of integrin-linked kinase in capillary/tube-like network formation of human vascular endothelial cells
Angiogenesis is a complex process involving an ECM and vascular endothelial cells (EC), and is regulated by various angiogenic factors including VEGF. The ability to form a capillary/tube-like network is a specialized function of EC. Therefore, in vitro angiogenesis was assessed by a capillary/tube-like network formation assay. There are three angiogenic parameters: capillary length, number of capillaries, and relative capillary area per field. We evaluated capillary length per field in the assay. VEGF promoted capillary/tube-like network formation of EC in a type I collagen gel matrix in vitro. Moreover, we demonstrated the involvement of ILK in a VEGF signaling pathway mediating capillary/tube-like network formation of EC using dominant-negative, kinase deficient ILK. This is a straightforward assay to monitor responses of human vascular endothelial cells
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