Search results for "Flow cytometry"
showing 10 items of 814 documents
Flow cytometry diagnosis in myelodysplastic syndrome: Current practice in Latin America and comparison with other regions of the world
2019
Background: Flow cytometry (FC) is a valuable tool for the diagnosis of myelodysplastic syndromes (MDS). We present results of a survey carried out to evaluate FC current practice for MDS diagnosis in Latin America (LA), focusing on markers used and characteristics of the clinical diagnostic report. Compliance to IMDSflow recommendations was also evaluated. These practices were then compared with those used in other countries. Methods: An online survey was sent through the Grupo Latino-Americano de Mielodisplasia to LA cytometrists and other international scientific societies. Results: 91 responses from 15 LA countries were received. The median of the number of markers used was 20 +/- 4.5, …
Laurus nobilis L. Seed Extract Reveals Collateral Sensitivity in Multidrug-Resistant P-Glycoprotein-Expressing Tumor Cells.
2015
The frequent failure of standard cancer chemotherapy requires the development of novel drugs capable of killing otherwise drug-resistant tumors. Here, we have investigated a chloroform extract of Laurus nobilis seeds. Fatty acids and 23 constituents of the volatile fraction were identified by gas chromotography/flame ionization detection (GC/FID) and gas chromatography/mass spectrometry (GC/MS), in good agreement with (1)H NMR (nuclear magnetic resonance) spectrum. Multidrug-resistant P-glycoprotein-expressing CEM/ADR5000 leukemia cells were hypersensitive (collaterally sensitive) toward this extract compared to drug-sensitive CCRF-CEM cells, whereas CEM/ADR5000 cells were 2586-fold resista…
Allorestricted T lymphocytes with a high avidity T-cell receptor towards NY-ESO-1 have potent anti-tumor activity.
2009
The cancer-testis antigen NY-ESO-1 has been targeted as a tumor-associated antigen by immunotherapeutical strategies, such as cancer vaccines. The prerequisite for a T-cell-based therapy is the induction of T cells capable of recognizing the NY-ESO-1-expressing tumor cells. In this study, we generated human T lymphocytes directed against the immunodominant NY-ESO-1(157-165) epitope known to be naturally presented with HLA-A*0201. We succeeded to isolate autorestricted and allorestricted T lymphocytes with low, intermediate or high avidity TCRs against the NY-ESO-1 peptide. The avidity of the established CTL populations correlated with their capacity of lysing HLA-A2-positive, NY-ESO-1-expre…
Comparative activity of idarubicin and idarubicinol in combination with cyclosporin A in multidrug-resistant leukemia cells
1996
4-Demethoxydaunorubicin (idarubicin, IDA) is an anthracycline that has shown good cytotoxic activity in vitro against tumor cell lines displaying the multidrug-resistant (MDR) phenotype. IDA is converted in the liver into idarubicinol (2HIDA) and, in this form, seems to exert its antitumoral activity in vivo. Recent studies have shown that 2HIDA has tumoricidal activity similar to that of the parent drug when tested in vitro in sensitive neoplastic cells. In this work we compared in vitro the effects of IDA and 2HIDA used alone and in combination with 2 microM cyclosporin A (CyA) in the MDR leukemic cell lines FLCR and K562R and in their sensitive parent cell lines FLC and K562. IDA and 2HI…
Selective induction of apoptosis in multidrug resistant HL60R cells by the thiazolobenzoimidazole derivative 1-(2,6-difluorophenyl)-1H,3H-thiazolo [3…
1999
We investigated the antitumour effects of 1-(2,6-difluorophenyl)-1H,3H-thiazolo [3,4-a]benzimidazole (TBZ) a new anti-HIV-1 agent, on human promyelocytic HL60 leukaemia, both a parental and a multidrug resistant form (HL60R). HL60R overexpresses P-glycoprotein and, like HL60, lacks p53 protein expression. HL60 and HL60R show similar levels of Bcl-2 protein. In contrast to the conventional chemotherapeutic agents daunorubicin, etoposide and mitoxantrone, TBZ caused equal or even greater cytotoxicity in HL60R than in HL60, and this result was associated with a more marked induction of apoptosis in the drug resistant cells. The antitumour activity of TBZ occurred in the range of concentrations…
Managing Multi-center Flow Cytometry Data for Immune Monitoring.
2014
With the recent results of promising cancer vaccines and immunotherapy 1 – 5 , immune monitoring has become increasingly relevant for measuring treatment-induced effects on T cells, and an essential tool for shedding light on the mechanisms responsible for a successful treatment. Flow cytometry is the canonical multi-parameter assay for the fine characterization of single cells in solution, and is ubiquitously used in pre-clinical tumor immunology and in cancer immunotherapy trials. Current state-of-the-art polychromatic flow cytometry involves multi-step, multi-reagent assays followed by sample acquisition on sophisticated instruments capable of capturing up to 20 parameters per cell at a…
Effects of resveratrol analogs on cell cycle progression, cell cycle associated proteins and 5fluoro-uracil sensitivity in human derived colon cancer…
2009
International audience; Epidemiological studies suggested that trans-resveratrol, a wine grape component, could prevent malignant tumor development. This compound also demonstrated cytostatic and cytotoxic effects on tumor cells in vitro. To obtain trans-resveratrol derivatives with a better cellular uptake and enhanced antiproliferative effects, we synthesized a triacetate derivative as well as an oligomer, epsilon-viniferin and its acetylated form, epsilon-viniferin penta-acetate. We also obtained vineatrol, a wine grape shoot extract that associates several polyphenols that may act synergistically, including trans-resveratrol and epsilon-viniferin. We show here that resveratrol triacetat…
Abstract 3100: Replacing fetal calf serum by human platelet lysate in cancer research and toxicology
2018
Abstract Experiments with cultured mammalian cells represent a common in vitro alternative to animal experiments. Fetal calf serum (FCS) is the most commonly used medium supplement. FCS contains a mixture of largely undefined growth factors and cytokines. Since FCS is received from unborn calves older than three months, it represents a massive burden for the pregnant cows and their fetuses. A needle is inserted into the heart of the fetus to collect blood. Since the animal is not under anesthesia, it may suffer pain and discomfort. Furthermore, the undefined nature of FCS is a source of experimental variation, undesired immune responses, and possible contaminations. Thus, alternative, defin…
Presence of the Transmembrane Protein Neuropilin in Cytokine-induced Killer Cells
2020
Background/aim Cytokine-induced killer (CIK) cells are a heterogenous population of immune cells showing promising applications in immunotherapeutic cancer treatment. Neuropilin (NRP) proteins have been proven to play an important role in cancer development and prognosis. In this study, CIK cells were tested for expression of NRPs, transmembrane proteins playing a role in the proliferation and survival of cancer cells. Materials and methods CIK cells were analyzed at different time points via flow cytometry and quantitative real-time polymerase chain reaction for neuropilin expression. Results Phenotyping results showed CIK cells having developed properly, and low levels of NRP2 were detect…
Bispecific antibodies targeting tumor-associated antigens and neutralizing complement regulators increase the efficacy of antibody-based immunotherap…
2015
The efficacy of antibody-based immunotherapy is due to the activation of apoptosis, the engagement of antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity (CDC). We developed a novel strategy to enhance CDC using bispecific antibodies (bsAbs) that neutralize the C-regulators CD55 and CD59 to enhance C-mediated functions. Two bsAbs (MB20/55 and MB20/59) were designed to recognize CD20 on one side. The other side neutralizes CD55 or CD59. Analysis of CDC revealed that bsAbs could kill 4-25 times more cells than anti-CD20 recombinant antibody in cell lines or cells isolated from patients with chronic lymphocytic leukemia. The pharmacokinetics of the bsAbs was evaluate…