scholarly journals A Novel High-Throughput Technique for Identifying Monoclonal Antibodies capable of Death Receptor Induced Apoptosis

2009 ◽  
Vol 2 ◽  
pp. JCD.S3660
Author(s):  
Hang Fai Kwok ◽  
Julie A. Gormley ◽  
Christopher J. Scott ◽  
James A. Johnston ◽  
Shane A. Olwill

The study of death receptor family induced apoptosis has gained momentum in recent years with the knowledge that therapeutic antibodies targeting DR4 and DR5 (death receptor's 4 and 5) have proved efficacious in multiple clinical trials. The therapeutic rationale is based on targeting and amplifying a tumour tissues normal cell death programme (apoptosis). While advances in the targeting of DR4 and DR5 have been successful the search for an agonistic antibody to another family member, the Fas receptor, has proven more elusive. This is partly due to the differing in vitro and in vivo characteristics of individual antibodies. In order to induce Fas targeted cell death an antibody must be capable of binding to and trimerising the receptor. It has been shown that antibodies capable of performing this function in vivo, with the assistance of tumour associated cells, do not always induce apoptosis in vitro. As a result the use of current methodologies to detect functional antibodies in vitro may have dismissed potential therapeutic candidates ('false negative'). Here we report a novel high throughput screening technique which artificially cross-links antibodies bound to the Fas receptor. By combining this process with Annexin-V and Prodidium Iodide (PI) staining we can select for antibodies which have the potential to induce apoptosis in vivo.

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Zhou Fang ◽  
Junjian Chen ◽  
Ye Zhu ◽  
Guansong Hu ◽  
Haoqian Xin ◽  
...  

AbstractPeptides are widely used for surface modification to develop improved implants, such as cell adhesion RGD peptide and antimicrobial peptide (AMP). However, it is a daunting challenge to identify an optimized condition with the two peptides showing their intended activities and the parameters for reaching such a condition. Herein, we develop a high-throughput strategy, preparing titanium (Ti) surfaces with a gradient in peptide density by click reaction as a platform, to screen the positions with desired functions. Such positions are corresponding to optimized molecular parameters (peptide densities/ratios) and associated preparation parameters (reaction times/reactant concentrations). These parameters are then extracted to prepare nongradient mono- and dual-peptide functionalized Ti surfaces with desired biocompatibility or/and antimicrobial activity in vitro and in vivo. We also demonstrate this strategy could be extended to other materials. Here, we show that the high-throughput versatile strategy holds great promise for rational design and preparation of functional biomaterial surfaces.


Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1446
Author(s):  
Tingting Jin ◽  
Jun Lin ◽  
Yingchao Gong ◽  
Xukun Bi ◽  
Shasha Hu ◽  
...  

Both calcium-independent phospholipase A2 beta (iPLA2β) and endoplasmic reticulum (ER) stress regulate important pathophysiological processes including inflammation, calcium homeostasis and apoptosis. However, their roles in ischemic heart disease are poorly understood. Here, we show that the expression of iPLA2β is increased during myocardial ischemia/reperfusion (I/R) injury, concomitant with the induction of ER stress and the upregulation of cell death. We further show that the levels of iPLA2β in serum collected from acute myocardial infarction (AMI) patients and in samples collected from both in vivo and in vitro I/R injury models are significantly elevated. Further, iPLA2β knockout mice and siRNA mediated iPLA2β knockdown are employed to evaluate the ER stress and cell apoptosis during I/R injury. Additionally, cell surface protein biotinylation and immunofluorescence assays are used to trace and locate iPLA2β. Our data demonstrate the increase of iPLA2β augments ER stress and enhances cardiomyocyte apoptosis during I/R injury in vitro and in vivo. Inhibition of iPLA2β ameliorates ER stress and decreases cell death. Mechanistically, iPLA2β promotes ER stress and apoptosis by translocating to ER upon myocardial I/R injury. Together, our study suggests iPLA2β contributes to ER stress-induced apoptosis during myocardial I/R injury, which may serve as a potential therapeutic target against ischemic heart disease.


Author(s):  
I.V. Leshkova ◽  
◽  
O.V. Dolgih ◽  
O.YU. Ustinova

Abstract. Introduction. The protection of the reproductive health of the working-age population is the most important direction of State policy. In 5-15% of cases, the causes of reproductive dysfunction are immunological disorders. Benzene belongs to the group of industrial reprotoxicants, however, its effect of benzene on the reproductive system has not been sufficiently studied. Objective: to study the immunological aspects of the effect of benzene on the reproductive system. Methods. We examined 50 men exposed to benzene with reproductive disorders (26-49 years old), as well as 4 workers with normal sexual function aged 53-60 years. Spontaneous and induced changes in the cellular expression of apoptosis markers were studied. For the study, the ANNEXIN V-FITC/7-AAD kit was used for the detection of cells that have undergone apoptosis. The experiment was conducted in vitro using a biological medium (ejaculate). A factor of the chemical nature was benzene. Results. According to the results of the comparative analysis, there were no significant deviations of pathogenetic tests of immunological markers in comparison with the reference level in the spontaneous expression samples, but there was an excess of expression of the CD95 + cell death receptor (p<0.05) in 30% of the samples examined, and a decrease in the number of Annexin V-FITC+7AAD negative cells (without reaching the significance level) in samples with a load of (15%). There was a difference in the expression levels of CD95+ and CD25+ CD-reception indicators by 20% and 10% in relation to the spontaneous level (p<0.05). Representatives of the chemical group of aromatic hydrocarbons realize reprotoxicity, using the mechanism of excessive induction of the membrane signaling of the cell death receptor, accelerate the natural program of cell death by approximately 20% compared to the state of reproductive cells that were not stimulated. Conclusion. At the present stage, one of the tasks of occupational medicine is to study the effect of chemicals on the processes of reproduction, to develop new approaches to assessing the risk of their impact on the reproductive health of workers.


Molecules ◽  
2020 ◽  
Vol 25 (8) ◽  
pp. 1780 ◽  
Author(s):  
Zaira Tavarez-Santamaría ◽  
Nadia J. Jacobo-Herrera ◽  
Leticia Rocha-Zavaleta ◽  
Alejandro Zentella-Dehesa ◽  
Beatriz del Carmen Couder-García ◽  
...  

Parthenium argentatum (Gray), commonly known as guayule, has been used to obtain natural rubber since the beginning of the 20th century. Additionally, the so called “resin” is a waste product derived from the industrial process. The cycloartane-type triterpene Argentatin A (AA) is one of the main constituents of the industrial waste resin. In this study we evaluated the AA anticancer activity both in vitro and in vivo in the HCT116 colon cancer cells. The apoptosis promotion of AA was assessed by the annexin V/propidium iodide (PI) assay. The senescence was evaluated for SA-β-galactosidase, and PCNA was used as a marker of proliferation. Its antitumor activity was evaluated using a xenograft mouse model. The results indicated that AA-induced apoptosis in HCT-116 cells and was positively stained for SA-β-galactosidase. In the xenografted mice test, the administration of AA at the dose of 250 mg/kg three times a week for 21 days reduced tumor growth by 78.1%. A comparable tumor reduction was achieved with cisplatin at the dose of 2 mg/kg administered three times a week for 21 days. However, nude mice treated with AA did not lose weight, as they did remarkably when treated with cisplatin. Furthermore, the animals treated with AA showed similar blood profiles as the healthy control group. These data indicate the low toxicity of AA compared to that shown by cisplatin.


2002 ◽  
Vol 22 (15) ◽  
pp. 5419-5433 ◽  
Author(s):  
Susanne M. A. Lens ◽  
Takao Kataoka ◽  
Karen A. Fortner ◽  
Antoine Tinel ◽  
Isabel Ferrero ◽  
...  

ABSTRACT The caspase 8 inhibitor c-FLIPL can act in vitro as a molecular switch between cell death and growth signals transmitted by the death receptor Fas (CD95). To elucidate its function in vivo, transgenic mice were generated that overexpress c-FLIPL in the T-cell compartment (c-FLIPL Tg mice). As anticipated, FasL-induced apoptosis was inhibited in T cells from the c-FLIPL Tg mice. In contrast, activation-induced cell death of T cells in c-FLIPL Tg mice was unaffected, suggesting that this deletion process can proceed in the absence of active caspase 8. Accordingly, c-FLIPL Tg mice differed from Fas-deficient mice by showing no accumulation of B220+ CD4− CD8− T cells. However, stimulation of T lymphocytes with suboptimal doses of anti-CD3 or antigen revealed increased proliferative responses in T cells from c-FLIPL Tg mice. Thus, a major role of c-FLIPL in vivo is the modulation of T-cell proliferation by decreasing the T-cell receptor signaling threshold.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3842-3842
Author(s):  
Dharminder Chauhan ◽  
Ajita V. Singh ◽  
Madhavi Bandi ◽  
Noopur Raje ◽  
Robert L Schlossman ◽  
...  

Abstract Abstract 3842 Poster Board III-778 Background and Rationale Vascular disrupting agents (VDAs) act via selectively disrupting established tumor vasculature and have shown remarkable clinical success as anti-cancer therapies. NPI-2358 is a novel VDA with a distinct structure and mechanism of action from other available VDAs. NPI-2358 binds to the colchicine-binding site of beta-tubulin preventing polymerization and disrupting the cytoplasmic microtubule network, thereby causing loss of vascular endothelial cytoskeletal function, and inducing cytotoxicity in cancer cells. Here, we examined the anti-angiogenic and anti-tumor activity of NPI-2358 in multiple myeloma (MM) cells using both in vitro and in vivo model systems. Material and Methods We utilized MM.1S, MM.1R, RPMI-8226, U266, and INA-6 human MM cell lines, as well as purified tumor cells from MM patients relapsing after prior anti-MM therapies. Cell viability/apoptosis assays were performed using MTT, trypan blue exclusion, and Annexin V/PI staining. Angiogenesis was measured in vitro using Matrigel capillary-like tube structure formation assays: Since human vascular endothelial cells (HUVECs) plated onto Matrigel differentiate and form capillary-like tube structures similar to in vivo neovascularization, this assay measures anti-angiogenic effects of drugs/agents. Migration assays were performed using transwell insert assays. Immunoblot analysis was performed using antibodies to caspase-8, caspase-9, caspase-3, PARP, Bcl-2, Bax, pJNK and GAPDH. Statistical significance was determined using a Student t test. Results Treatment of MM.1S, RPMI-8226, MM.1R, INA-6, and KMS-12BM with NPI-2358 for 24h induces a dose-dependent significant (P < 0.005) decrease in viability of all cell lines (IC50 range: 5-8 nM; n=3). To determine whether NPI-2358-induced decrease in viability is due to apoptosis, MM cell lines were treated with NPI-2358 for 24h; harvested, and analyzed for apoptosis using Annexin V/PI staining. A significant increase in NPI-2358-induced apoptosis was observed in all MM cell lines (% Annexin V+/PI- apoptotic cells: MM.1S, 48 ± 2.3%; MM.1R, 46.6 ± 3.1%; RPMI-8226, 61.7 ± 4.5%; and INA-6, 59.9 ± 3.2%; P < 0.05; n=3). Importantly, NPI-2358 decreased viability of freshly isolated MM cells from patients (IC50 range: 3-7 nM; P < 0.005), without affecting the viability of normal peripheral blood mononuclear cells, suggesting specific anti-MM activity and a favorable therapeutic index for NPI-2358. Examination of in vitro angiogenesis using capillary-like tube structure formation assay showed that even low doses of NPI-2358 (7 nM treatment for 12h; IC50: 20 nM at 24h) significantly decreased tubule formation in HUVECs (70-80% decrease; P < 0.05). Transwell insert assays showed a marked reduction in serum-dependent migration of NPI-2358-treated MM cells (42 ± 2.1% inhibition in NPI-2358-treated vs. control; P < 0.05). NPI-2358 at the concentrations tested (5 nM for 12h) in the migration assays did not affect survival of MM cells (> 95% viable cells). A similar anti-migration activity of NPI-2358 was noted against HUVEC cells (48 ± 1.7% decrease in migration; P < 0.05). Mechanistic studies showed that NPI-2358-induced apoptosis was associated with activation of caspase-8, caspase-9, caspase-3 and PARP. Importantly, treatment of MM.1S cells with NPI-2358 (5 nM) triggered phosphorylation of c-Jun amino-terminal kinase (JNK), a classical stress response protein, without affecting Bcl-2 family members Bax and Bcl-2. Blockade of JNK using dominant negative strategy markedly abrogated NPI-2358-induced apoptosis. Conclusion Our preclinical data provide evidence for remarkable anti-angiogenic and anti-tumor activity of NPI-2358 against MM cells, without significant toxicity in normal cells. Ongoing studies are examining in vivo anti-MM activity of NPI-2358 in animal models. Importantly, a Phase-1 study of NPI-2358 as a single agent in patients with advanced malignancies (lung, prostrate and colon cancer) has already established a favorable pharmacokinetic, pharmacodynamic and safety profile; and, a Phase-2 study of the combination of NPI-2358 and docetaxel in non-small cell lung cancer showed encouraging safety, pharmacokinetic and activity data. These findings, coupled with our preclinical studies, provide the framework for the development of NPI-2358-based novel therapies to improve patient outcome in MM. Disclosures: Chauhan: Nereus Pharmaceuticals, Inc: Consultancy. Lloyd:Nereus Pharmaceuticals, In: Employment. Palladino:Nereus Pharmaceuticals, Inc: Employment. Anderson:Nereus Pharmaceuticals, Inc: Consultancy.


2005 ◽  
Vol 25 (5) ◽  
pp. 2000-2013 ◽  
Author(s):  
Niklas Finnberg ◽  
Joshua J. Gruber ◽  
Peiwen Fei ◽  
Dorothea Rudolph ◽  
Anka Bric ◽  
...  

ABSTRACT DR5 (also called TRAIL receptor 2 and KILLER) is an apoptosis-inducing membrane receptor for tumor necrosis factor-related apoptosis-inducing ligand (also called TRAIL and Apo2 ligand). DR5 is a transcriptional target of p53, and its overexpression induces cell death in vitro. However, the in vivo biology of DR5 has remained largely unexplored. To better understand the role of DR5 in development and in adult tissues, we have created a knockout mouse lacking DR5. This mouse is viable and develops normally with the exception of having an enlarged thymus. We show that DR5 is not expressed in developing embryos but is present in the decidua and chorion early in development. DR5-null mouse embryo fibroblasts expressing E1A are resistant to treatment with TRAIL, suggesting that DR5 may be the primary proapoptotic receptor for TRAIL in the mouse. When exposed to ionizing radiation, DR5-null tissues exhibit reduced amounts of apoptosis compared to wild-type thymus, spleen, Peyer's patches, and the white matter of the brain. In the ileum, colon, and stomach, DR5 deficiency was associated with a subtle phenotype of radiation-induced cell death. These results indicate that DR5 has a limited role during embryogenesis and early stages of development but plays an organ-specific role in the response to DNA-damaging stimuli.


2004 ◽  
Vol 9 (8) ◽  
pp. 687-694 ◽  
Author(s):  
Yoonsuk Lee ◽  
Dong-Ku Kang ◽  
Soo-Ik Chang ◽  
Moon Hi Han ◽  
In-Cheol Kang

Protein microarray is an emerging technology that makes high-throughput analysis possible for protein-protein interactions and analysis of proteome and biomarkers in parallel. The authors investigated the application of a novel protein microarray chip, Proteo Chip, in new drug discovery. Integrin αvβ3 microarray immobilized on the Proteo Chip was employed to screen new active peptides against the integrin from multiple hexapeptide sublibraries of a positional scanning synthetic peptide combinatorial library (PS-SPCL). The integrin αvβ3-vitronectin interaction was successfully demonstrated on the integrin microarray in a dose-dependent manner andwas inhibited not only by the syntheticRGDpeptide but also by various integrin antagonists on the integrin microarray chip. Novel peptide ligands with high affinity to the integrin were also identified from the peptide libraries with this chip-based screening system by a competitive inhibition assay in a simultaneous and highthroughput fashion. The authors have confirmed antiangiogenic functions of the novel peptides thus screened through an in vitro and in vivo angiogenesis assay. These results provide evidence that the Proteo Chip is a promising tool for highthroughput screening of lead molecules in new drug development.


2013 ◽  
Vol 06 (04) ◽  
pp. 1350046
Author(s):  
YING-YAO QUAN ◽  
CHAOYANG WANG ◽  
XIAO-PING WANG ◽  
TONG-SHENG CHEN

Recently, we found that high concentration of taxol (70 μM) induced cell death with cytoplasm vacuolization, the typical characteristic of both paraptosis and oncosis, in human lung carcinoma (ASTC-a-1) cells. This report was designed to further determine the form of taxol-induced cell death with cytoplasm vacuolization. It is generally considered that the cytoplasm vacuolization in oncosis due to the swelling of endoplasmic reticulum (ER), mitochondria, lysosomes and nuclei occurs after the loss of mitochondrial membrane potential (ΔΨm). However, flow cytometry (FCM) analysis showed that taxol-induced cytoplasm vacuolization preceded the loss of ΔΨm. Moreover, taxol treatment did not induce the collapse of microtubule, the typical characteristic of oncosis. These data demonstrated that taxol-induced cell death with cytoplasm vacuolization is not oncosis. FCM analysis by Annexin V-FITC/PI apoptosis detection kit further demonstrated that taxol-induced cell death with cytoplasm vacuolization is not apoptosis. In conclusion, in combination with our recent in vitro and in vivo data, this report further demonstrates that high concentration of taxol induces cell death with cytoplasm vacuolization in paraptosis-like but not oncosis fashion.


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