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Diaz D, Barcenilla H, Prieto A, Monserrat J, Alvarez-Mon M. Accurate Enumeration of Apoptotic Cancer Cells Using Flow Cytometry. Methods Mol Biol 2022; 2543:35-44. [PMID: 36087257 DOI: 10.1007/978-1-0716-2553-8_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The frequency of apoptotic cells in a given phenotypically defined population is usually calculated the apoptotic index (AI), i.e., the percentage of apoptotic cells displaying a specific linage antigen (LAg) within a population of cells that remain unfragmented and retain the expression of the LAg. However, this approach has two major limitations. Firstly, apoptotic cells fragment into apoptotic bodies that later disintegrate. Secondly, apoptotic cells frequently lose, partially or even completely, the cell surface expression of the LAg used for the identification of specific cell subsets. The present chapter will describe a flow cytometry method to calculate the apoptotic rate (AR) that takes into account both cell fragmentation and loss of lineage antigen expression on measurement of apoptosis using flow cytometry ratiometric cell enumeration that emerges as a more accurate method of measurement of the occurrence of apoptosis in normal and tumoral cell cultures.
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Affiliation(s)
- David Diaz
- Department of Medicine, University of Alcalá, Madrid, Spain.
| | - Hugo Barcenilla
- Department of Biomedical and Clinical sciences, Division of Children's and Women's Health, Faculty of Health Sciences, Linköping University, Linköping, Sweden
| | - Alfredo Prieto
- Department of Medicine, University of Alcalá, Madrid, Spain
| | | | - Melchor Alvarez-Mon
- Department of Medicine, University of Alcalá, Madrid, Spain
- Immune System Diseases and Oncology Service, University Hospital "Príncipe de Asturias", Alcalá de Henares, Madrid, Spain
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2
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Maeda FY, van Haaren JJ, Langley DB, Christ D, Andrews NW, Song W. Surface-associated antigen induces permeabilization of primary mouse B-cells and lysosome exocytosis facilitating antigen uptake and presentation to T-cells. eLife 2021; 10:66984. [PMID: 34704555 PMCID: PMC8589448 DOI: 10.7554/elife.66984] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 10/26/2021] [Indexed: 12/13/2022] Open
Abstract
B-cell receptor (BCR)-mediated antigen internalization and presentation are essential for humoral memory immune responses. Antigen encountered by B-cells is often tightly associated with the surface of pathogens and/or antigen-presenting cells. Internalization of such antigens requires myosin-mediated traction forces and extracellular release of lysosomal enzymes, but the mechanism triggering lysosomal exocytosis is unknown. Here, we show that BCR-mediated recognition of antigen tethered to beads, to planar lipid-bilayers or expressed on cell surfaces causes localized plasma membrane (PM) permeabilization, a process that requires BCR signaling and non-muscle myosin II activity. B-cell permeabilization triggers PM repair responses involving lysosomal exocytosis, and B-cells permeabilized by surface-associated antigen internalize more antigen than cells that remain intact. Higher affinity antigens cause more B-cell permeabilization and lysosomal exocytosis and are more efficiently presented to T-cells. Thus, PM permeabilization by surface-associated antigen triggers a lysosome-mediated B-cell resealing response, providing the extracellular hydrolases that facilitate antigen internalization and presentation.
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Affiliation(s)
- Fernando Y Maeda
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, United States
| | - Jurriaan Jh van Haaren
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, United States
| | - David B Langley
- Immunology Division, Garvan Institute of Medical Research, Darlinghurst, Australia
| | - Daniel Christ
- Immunology, Garvan Institute of Medical Research, Darlinghurst/Sydney, Australia
| | - Norma W Andrews
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, United States
| | - Wenxia Song
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, United States
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3
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Manfrini N, Ricciardi S, Miluzio A, Fedeli M, Scagliola A, Gallo S, Brina D, Adler T, Busch DH, Gailus-Durner V, Fuchs H, Hrabě de Angelis M, Biffo S. High levels of eukaryotic Initiation Factor 6 (eIF6) are required for immune system homeostasis and for steering the glycolytic flux of TCR-stimulated CD4 + T cells in both mice and humans. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2017; 77:69-76. [PMID: 28743432 DOI: 10.1016/j.dci.2017.07.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 07/21/2017] [Accepted: 07/21/2017] [Indexed: 06/07/2023]
Abstract
Eukaryotic Initiation Factor 6 (eIF6) is required for 60S ribosomal subunit biogenesis and efficient initiation of translation. Intriguingly, in both mice and humans, endogenous levels of eIF6 are detrimental as they act as tumor and obesity facilitators, raising the question on the evolutionary pressure that maintains high eIF6 levels. Here we show that, in mice and humans, high levels of eIF6 are required for proper immune functions. First, eIF6 heterozygous (het) mice show an increased mortality during viral infection and a reduction of peripheral blood CD4+ Effector Memory T cells. In human CD4+ T cells, eIF6 levels rapidly increase upon T-cell receptor activation and drive the glycolytic switch and the acquisition of effector functions. Importantly, in CD4+ T cells, eIF6 levels control interferon-γ (IFN-γ) secretion without affecting proliferation. In conclusion, the immune system has a high evolutionary pressure for the maintenance of a dynamic and powerful regulation of the translational machinery.
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Affiliation(s)
- Nicola Manfrini
- National Institute of Molecular Genetics "Romeo ed Enrica Invernizzi" - INGM, Via F. Sforza 35, 20122 Milan, Italy.
| | - Sara Ricciardi
- National Institute of Molecular Genetics "Romeo ed Enrica Invernizzi" - INGM, Via F. Sforza 35, 20122 Milan, Italy
| | - Annarita Miluzio
- National Institute of Molecular Genetics "Romeo ed Enrica Invernizzi" - INGM, Via F. Sforza 35, 20122 Milan, Italy
| | - Maya Fedeli
- Experimental Immunology Unit, Division of Immunology, Transplantation and Infectious Diseases, DIBIT, H. San Raffaele Scientific Institute, Via Olgettina 58, 20132 Milan, Italy
| | - Alessandra Scagliola
- National Institute of Molecular Genetics "Romeo ed Enrica Invernizzi" - INGM, Via F. Sforza 35, 20122 Milan, Italy; Department of Biosciences, University of Milan, Via Celoria 26, 20133 Milan, Italy
| | - Simone Gallo
- National Institute of Molecular Genetics "Romeo ed Enrica Invernizzi" - INGM, Via F. Sforza 35, 20122 Milan, Italy; Department of Biosciences, University of Milan, Via Celoria 26, 20133 Milan, Italy
| | - Daniela Brina
- Molecular Oncology Group, Institute of Oncology Research (IOR), Oncology Institute of Southern Switzerland (IOSI), Via Mirasole 22A, Bellinzona, Switzerland
| | - Thure Adler
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764 Neuherberg, Germany
| | - Dirk H Busch
- Institute for Medical Microbiology, Immunology and Hygiene, Technische Universität München, Trogerstrasse 30, 81675 Munich, Germany
| | - Valerie Gailus-Durner
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764 Neuherberg, Germany
| | - Helmut Fuchs
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764 Neuherberg, Germany
| | - Martin Hrabě de Angelis
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764 Neuherberg, Germany; Center of Life and Food Sciences Weihenstephan, Technische Universität München, 85354 Freising, Germany; German Center for Diabetes Research, 85764 Neuherberg, Germany
| | - Stefano Biffo
- National Institute of Molecular Genetics "Romeo ed Enrica Invernizzi" - INGM, Via F. Sforza 35, 20122 Milan, Italy; Department of Biosciences, University of Milan, Via Celoria 26, 20133 Milan, Italy.
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4
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Manfrini N, Ricciardi S, Miluzio A, Fedeli M, Scagliola A, Gallo S, Adler T, Busch DH, Gailus-Durner V, Fuchs H, de Angelis MH, Biffo S. Data on the effects of eIF6 downmodulation on the proportions of innate and adaptive immune system cell subpopulations and on thymocyte maturation. Data Brief 2017; 14:653-658. [PMID: 28924581 PMCID: PMC5591389 DOI: 10.1016/j.dib.2017.08.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 08/02/2017] [Accepted: 08/24/2017] [Indexed: 11/28/2022] Open
Abstract
The data described in this article are related to “High levels of eukaryotic Initiation Factor 6 (eIF6) are required for immune system homeostasis and for steering the glycolytic flux of TCR-stimulated CD4+ T cells in both mice and humans” (Manfrini et al., in press) [1]. eIF6 is a translation initiation factor required for ribosomal biogenesis (Sanvito et al., 1999) [2] and for proper translational initiation (Gallo and Manfrini, 2015; Miluzio et al., 2016) [3], [4] whose protein abundance requires tight regulation. Here we analyze by flow cytometry the effects of eIF6 depletion on proportions of specific innate and adaptive immune system subpopulations and on thymocyte maturation in mice.
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Affiliation(s)
- Nicola Manfrini
- National Institute of Molecular Genetics "Romeo ed Enrica Invernizzi" - INGM, via F. Sforza 35, 20122 Milan, Italy
| | - Sara Ricciardi
- National Institute of Molecular Genetics "Romeo ed Enrica Invernizzi" - INGM, via F. Sforza 35, 20122 Milan, Italy
| | - Annarita Miluzio
- National Institute of Molecular Genetics "Romeo ed Enrica Invernizzi" - INGM, via F. Sforza 35, 20122 Milan, Italy
| | - Maya Fedeli
- Experimental Immunology Unit, Division of Immunology, Transplantation and Infectious Diseases, DIBIT, H. San Raffaele Scientific Institute, via Olgettina 58, 20132 Milan, Italy
| | - Alessandra Scagliola
- National Institute of Molecular Genetics "Romeo ed Enrica Invernizzi" - INGM, via F. Sforza 35, 20122 Milan, Italy.,Department of Biosciences, University of Milan, Via Celoria 26, 20133 Milan, Italy
| | - Simone Gallo
- National Institute of Molecular Genetics "Romeo ed Enrica Invernizzi" - INGM, via F. Sforza 35, 20122 Milan, Italy.,Department of Biosciences, University of Milan, Via Celoria 26, 20133 Milan, Italy
| | - Thure Adler
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764 Neuherberg, Germany
| | - Dirk H Busch
- Institute for Medical Microbiology, Immunology and Hygiene, Technische Universität München, Trogerstrasse 30, 81675 Munich, Germany
| | - Valerie Gailus-Durner
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764 Neuherberg, Germany
| | - Helmut Fuchs
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764 Neuherberg, Germany
| | - Martin Hrabě de Angelis
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764 Neuherberg, Germany.,Center of Life and Food Sciences Weihenstephan, Technische Universität München, 85354 Freising, Germany.,German Center for Diabetes Research, 85764 Neuherberg, Germany
| | - Stefano Biffo
- National Institute of Molecular Genetics "Romeo ed Enrica Invernizzi" - INGM, via F. Sforza 35, 20122 Milan, Italy.,Department of Biosciences, University of Milan, Via Celoria 26, 20133 Milan, Italy
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Wang W, Gao L, Li Y, Li ZL, Gong M, Huang FZ, Chen YR, Zhang CX, Gao YY, Ma YG. The application of CD73 in minimal residual disease monitoring using flow cytometry in B-cell acute lymphoblastic leukemia. Leuk Lymphoma 2015; 57:1174-81. [PMID: 26436205 DOI: 10.3109/10428194.2015.1070153] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The expression of CD73 by flow cytometry (FC) in bone marrow (BM) specimens of B-cell acute lymphoblastic leukemia (B-ALL) with or without minimal residual disease (MRD) was studied, and its advantages were evaluated using the MRD assay. This study also detected the expression profile of CD73 in hematogones and mature B cells in BM specimens of 18 healthy donors. Results showed that the mean value of CD73 expression in MRD-positive B cells was 6-fold greater than that in the MRD negative ones. Also, 41.82% MRD-positive B-ALL cases expressed high CD73 and the sensitivity of CD73-based MRD detection reached 10(-4). Since the expression of CD73 increases with the maturation of normal B cells, it is better to mix it with CD34, CD10 and CD20 in one tube to prevent the disturbance of mature B cells. CD73 is recommended as an optional MRD marker for B-ALL patients by using FC.
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Affiliation(s)
- Wei Wang
- a Department of Hematology , China-Japan Friendship Hospital , Beijing , PR China
| | - Li Gao
- a Department of Hematology , China-Japan Friendship Hospital , Beijing , PR China
| | - Yan Li
- a Department of Hematology , China-Japan Friendship Hospital , Beijing , PR China
| | - Zhen-Ling Li
- a Department of Hematology , China-Japan Friendship Hospital , Beijing , PR China
| | - Ming Gong
- a Department of Hematology , China-Japan Friendship Hospital , Beijing , PR China
| | - Fan-Zhou Huang
- a Department of Hematology , China-Japan Friendship Hospital , Beijing , PR China
| | - Yan-Rong Chen
- a Department of Hematology , China-Japan Friendship Hospital , Beijing , PR China
| | - Chun-Xia Zhang
- a Department of Hematology , China-Japan Friendship Hospital , Beijing , PR China
| | - Ya-Yue Gao
- a Department of Hematology , China-Japan Friendship Hospital , Beijing , PR China
| | - Yi-Gai Ma
- a Department of Hematology , China-Japan Friendship Hospital , Beijing , PR China
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Diaz D, Prieto A, Reyes E, Barcenilla H, Monserrat J, Alvarez-Mon M. Flow cytometry enumeration of apoptotic cancer cells by apoptotic rate. Methods Mol Biol 2015; 1219:11-20. [PMID: 25308258 DOI: 10.1007/978-1-4939-1661-0_2] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Most authors currently quantify the frequency of apoptotic cells in a given phenotypically defined population after calculating the apoptotic index (AI), i.e., the percentage of apoptotic cells displaying a specific linage antigen (LAg) within a population of cells that remain unfragmented and retain the expression of the LAg. However, this approach has two major limitations. Firstly, apoptotic cells fragment into apoptotic bodies that later disintegrate. Secondly, apoptotic cells frequently lose, partially or even completely, the cell surface expression of the LAg used for the identification of specific cell subsets. This chapter describes a flow cytometry method to calculate the apoptotic rate (AR) that takes into account both cell fragmentation and loss of lineage antigen expression on measurement of apoptosis using flow cytometry ratiometric cell enumeration that emerges as a more accurate method of measurement of the occurrence of apoptosis in normal and tumoral cell cultures.
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Affiliation(s)
- David Diaz
- CNB-CSIC R&D Associated Unit, Department of Medicine, University of Alcalá, Carretera Madrid-Barcelona, Km 33.600, 28871, Alcalá de Henares, Madrid, Spain,
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7
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Diaz D, Chara L, Chevarria J, Ubeda M, Muñoz L, Barcenilla H, Sánchez MA, Moreno Z, Monserrat J, Albillos A, Prieto A, Alvarez-Mon M. Loss of surface antigens is a conserved feature of apoptotic lymphocytes from several mammalian species. Cell Immunol 2011; 271:163-72. [PMID: 21745657 DOI: 10.1016/j.cellimm.2011.06.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 05/20/2011] [Accepted: 06/15/2011] [Indexed: 01/13/2023]
Abstract
Human lymphocytes lose the expression of lineage antigens (LAgs) along apoptosis. Our aim was to extent our previous studies of LAg loss to rodent species, quantifying LAg expression on apoptotic murine lymphocytes using flow cytometry to measure alterations in cell permeability, phosphatidylserine exposure and caspase activation of CD3, CD5, CD4, CD8, CD19 and CD28 LAgs in highly purified lymphocyte populations. We found loss of expression by apoptotic cells of all LAgs studied in the three species analyzed except for CD3 antigen in mouse. We also found an early, rapid and dramatic reduction in the expression of CD28 by early apoptotic cells. We found several homologies across the three species in the kinetic of loss of several LAgs such as CD5, CD4 and CD28. These data suggest that the loss of expression of LAgs by apoptotic lymphocytes is a common and conserved feature of lymphocytes undergoing apoptosis in several mammalian species.
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Affiliation(s)
- David Diaz
- Department of Medicine, University of Alcalá, Madrid, Spain.
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Stemberger J, Witt V, Printz D, Geyeregger R, Fritsch G. Novel single-platform multiparameter FCM analysis of apoptosis: Significant differences between wash and no-wash procedure. Cytometry A 2011; 77:1075-81. [PMID: 20872888 DOI: 10.1002/cyto.a.20976] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
FCM is a generally accepted tool to analyze apoptosis. Unfortunately, the cell preparation of all commercial kits available includes cell washing known to cause cell loss which is most likely to affect apoptotic cells in particular. To address this, we developed a seven-color single-platform no-wash analysis technique and compared the results with those from an analogous procedure including cell washing. A five-color mAb cocktail was employed to address target cells by surface labeling, Yo-PRO-1® and DAPI were used to discriminate apoptotic and necrotic from viable cells. Cells were quantified on the basis of internal-standard fluorescent beads. Jurkat cells ACC 282 treated with camptothecin were employed to establish the staining procedure, which was then applied to blood cells collected by extracorporeal apheresis and treated with UV irradiation. Data evaluation showed that although each method by itself was highly reproducible (R(2) = 0.973), the numbers of apoptotic cells detected with the no-wash procedure were significantly higher than those obtained after cell washing (P = 6.6 E(-5), Wilcoxon Test). In addition, the observed differences increased with higher cell numbers (Bland and Altmann). We conclude that the described test is a feasible and reliable tool for apoptosis measurement and it provides results that are definitely closer to the truth than those obtained from kits that require cell washing.
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Affiliation(s)
- Julia Stemberger
- Children's Cancer Research Institute, St. Anna Kinderkrebsforschung, Vienna, Austria
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9
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Dworzak MN, Gaipa G, Schumich A, Maglia O, Ratei R, Veltroni M, Husak Z, Basso G, Karawajew L, Gadner H, Biondi A. Modulation of antigen expression in B-cell precursor acute lymphoblastic leukemia during induction therapy is partly transient: evidence for a drug-induced regulatory phenomenon. Results of the AIEOP-BFM-ALL-FLOW-MRD-Study Group. CYTOMETRY PART B-CLINICAL CYTOMETRY 2010; 78:147-53. [PMID: 20201055 DOI: 10.1002/cyto.b.20516] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Changes of antigen expression on residual blast cells of acute lymphoblastic leukemia (ALL) occur during induction treatment. Many markers used for phenotyping and minimal residual disease (MRD) monitoring are affected. Glucocorticoid (GC)-induced expression modulation has been causally suspected, however, subclone selection may also cause the phenomenon. METHODS We investigated this by following the phenotypic evolution of leukemic cells with flow cytometry from diagnosis to four time points during and after GC containing chemotherapy in the 20 (of 360 consecutive) B-cell precursor patients with ALL who had persistent MRD throughout. RESULTS The early expression changes of CD10 and CD34 were reversible after stop of GC containing chemotherapy. Modulation of CD20 and CD45 occurred mostly during the GC phase, whereas CD11a also changed later on. Blast cells at diagnosis falling into gates designed according to "shifted" phenotypes from follow-up did not form clusters and were frequently less numerous than later on. CONCLUSIONS Our data support the idea that drug-induced modulation rather than selection causes the phenomenon. The good message for MRD assessment is that modulation is transient in at least two (CD10 and CD34) of the five prominent antigens investigated and reverts to initial aberrant patterns after stop of GC therapy, whereas CD20 expression gains new aberrations exploitable for MRD detection.
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Affiliation(s)
- Michael N Dworzak
- Laboratory of Immunological Diagnostics, Children's Cancer Research Institute, Vienna, Austria.
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10
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Fuchs H, Gailus-Durner V, Adler T, Aguilar-Pimentel JA, Becker L, Calzada-Wack J, Da Silva-Buttkus P, Neff F, Götz A, Hans W, Hölter SM, Horsch M, Kastenmüller G, Kemter E, Lengger C, Maier H, Matloka M, Möller G, Naton B, Prehn C, Puk O, Rácz I, Rathkolb B, Römisch-Margl W, Rozman J, Wang-Sattler R, Schrewe A, Stöger C, Tost M, Adamski J, Aigner B, Beckers J, Behrendt H, Busch DH, Esposito I, Graw J, Illig T, Ivandic B, Klingenspor M, Klopstock T, Kremmer E, Mempel M, Neschen S, Ollert M, Schulz H, Suhre K, Wolf E, Wurst W, Zimmer A, Hrabě de Angelis M. Mouse phenotyping. Methods 2010; 53:120-35. [PMID: 20708688 DOI: 10.1016/j.ymeth.2010.08.006] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Revised: 08/06/2010] [Accepted: 08/06/2010] [Indexed: 12/13/2022] Open
Abstract
Model organisms like the mouse are important tools to learn more about gene function in man. Within the last 20 years many mutant mouse lines have been generated by different methods such as ENU mutagenesis, constitutive and conditional knock-out approaches, knock-down, introduction of human genes, and knock-in techniques, thus creating models which mimic human conditions. Due to pleiotropic effects, one gene may have different functions in different organ systems or time points during development. Therefore mutant mouse lines have to be phenotyped comprehensively in a highly standardized manner to enable the detection of phenotypes which might otherwise remain hidden. The German Mouse Clinic (GMC) has been established at the Helmholtz Zentrum München as a phenotyping platform with open access to the scientific community (www.mousclinic.de; [1]). The GMC is a member of the EUMODIC consortium which created the European standard workflow EMPReSSslim for the systemic phenotyping of mouse models (http://www.eumodic.org/[2]).
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Affiliation(s)
- Helmut Fuchs
- Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstraße 1, 85764 München/Neuherberg, Germany
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Diaz D, Prieto A, Reyes E, Barcenilla H, Monserrat J, Alvarez-Mon M. Flow cytometry enumeration of apoptotic cancer cells by apoptotic rate. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2008; 414:23-33. [PMID: 18175809 DOI: 10.1007/978-1-59745-339-4_3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Most authors currently quantify the frequency of apoptotic cells in a given phenotypically defined population after calculating the apoptotic index (AI), that is, the percentage of apoptotic cells displaying a specific lineage antigen (LAg) within a population of cells that remain unfragmented and retain the expression of the LAg. However, this approach has two major limitations. First, apoptotic cells fragment into apoptotic bodies that later disintegrate. Second, apoptotic cells frequently lose, partially or even completely, the cell surface expression of the LAg used for the identification of specific cell subsets. This chapter will describe a flow cytometry method to calculate the apoptotic rate (AR) that takes into account both cell fragmentation and loss of LAg expression on measurement of apoptosis using flow cytometry ratiometric cell enumeration that emerges as a more accurate method of measurement of the occurrence of apoptosis in normal and tumoral cell cultures.
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Affiliation(s)
- David Diaz
- CNB-CSIC R&D Associated Unit, Department of Medicine, University of Alcalá, Alcalá de Henares, Maddrid, Spain
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12
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Ribeiro E, Matarraz Sudón S, de Santiago M, Lima CSP, Metze K, Giralt M, Saad STO, de Matos AO, Lorand-Metze I. Maturation-associated immunophenotypic abnormalities in bone marrow B-lymphocytes in myelodysplastic syndromes. Leuk Res 2006; 30:9-16. [PMID: 16005514 DOI: 10.1016/j.leukres.2005.05.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2005] [Revised: 05/17/2005] [Accepted: 05/18/2005] [Indexed: 11/27/2022]
Abstract
Recent studies concerning the pathophysiology of myelodysplastic syndromes (MDS) have shown evidences for the existence of complex interactions between hematopoietic stem cells and the bone marrow (BM) microenvironment. We analyzed the B-lymphocyte maturation in BM of patients with MDS. For this purpose, 41 newly-diagnosed patients were analyzed. Enumeration and characterization of CD34+ and CD34- B-cell precursors and mature B-lymphocytes was performed using multiparameter flow cytometry. BM from eight transplant donors and six orthopedic surgery patients were used as controls. CD34+/CD45(lo) B-cells were found in 17/22 patients with RA/RARS and in 5/13 with RAEB. In patients with RAEB-t and CMML no CD34+ B-cell precursors could be detected. A positive correlation was found between CD34+ and CD34- B-cell precursors (r=0.52). CD34+ B-cell precursors presented an inverse correlation with BM percentage of blasts and peripheral leukocytes and a positive one with hemoglobin. Asynchronous antigen expression (CD19+/CD79a- cells) was found in 7/11 cases of RA/RARS and 6/18 cases of RAEB in which this phenotype was examined. Abnormal patterns of expression for at least one antigen was found in 91% of RA/RARS cases and in 74% of RAEB. Underexpression of TdT and CD79a were the most frequent abnormalities. Our results present evidences of an abnormal B-cell maturation in MDS. This may be an evidence that B-lymphocytes are derived of the abnormal clone. But it may also be the consequence of influences of abnormalities of BM microenvironment leading to an impaired commitment and maturation of the B-cell line in MDS. Studies performed with purified well-characterized B-cells may further elucidate these abnormalities.
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Diaz D, Prieto A, Barcenilla H, Monserrat J, Sánchez MA, Reyes E, Hernandez-Fuentes MP, de la Hera A, Orfao A, Alvarez-Mon M. Accurate apoptosis measurement requires quantification of loss of expression of surface antigens and cell fragmentation. Cytometry A 2006; 69:240-8. [PMID: 16528734 DOI: 10.1002/cyto.a.20251] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND The use of ratiometric cell enumeration methods emerges as a more accurate method of measurement of the occurrence of apoptosis in cell cultures. These new flow cytometry methods were used to quantify the impact of cell fragmentation and loss of lineage antigen (LAg) expression on measurement of apoptosis. METHODS Highly purified human lymphocyte populations were negatively sorted and cultured for 24 h. Apoptotic cells were identified using annexin V, 7-amino-actinomycin D and their LAgs were stained with antibodies. A new indicator, the apoptotic rate, was used to determine apoptosis occurrence and its validity compared with the widely accepted percentage of apoptotic cells (apoptotic index, AI). RESULTS Loss of LAg expression and cell fragmentation were observed under all conditions assayed and for all cell populations studied. CONCLUSIONS Current methods for quantifying of apoptosis involving AI systematically underestimate apoptosis occurrence in all populations and conditions, especially among cells undergoing spontaneous apoptosis.
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Affiliation(s)
- David Diaz
- CNB-CSIC R&D Associated Unit, Department of Medicine, University of Alcalá, Alcalá de Henares, Madrid, Spain
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van der Sluijs-Gelling AJ, van der Velden VHJ, Roeffen ETJM, Veerman AJP, van Wering ER. Immunophenotypic modulation in childhood precursor-B-ALL can be mimicked in vitro and is related to the induction of cell death. Leukemia 2005; 19:1845-7. [PMID: 16107891 DOI: 10.1038/sj.leu.2403911] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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van der Sluijs-Gelling AJ, van der Velden VHJ, Roeffen ETJM, Veerman AJP, van Wering ER. Reply to Gaipa et al. Leukemia 2005; 19:1858. [PMID: 16107890 DOI: 10.1038/sj.leu.2403913] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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