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Montanari M, Burattini S, Ciacci C, Ambrogini P, Carloni S, Balduini W, Lopez D, Panza G, Papa S, Canonico B. Automated–Mechanical Procedure Compared to Gentle Enzymatic Tissue Dissociation in Cell Function Studies. Biomolecules 2022; 12:biom12050701. [PMID: 35625628 PMCID: PMC9138555 DOI: 10.3390/biom12050701] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/11/2022] [Accepted: 05/12/2022] [Indexed: 02/04/2023] Open
Abstract
The first step to obtain a cellular suspension from tissues is the disaggregation procedure. The cell suspension method has to provide a representative sample of the different cellular subpopulations and to maximize the number of viable functional cells. Here, we analyzed specific cell functions in cell suspensions from several rat tissues obtained by two different methods, automated–mechanical and enzymatic disaggregation. Flow cytometric, confocal, and ultrastructural (TEM) analyses were applied to the spleen, testis, liver and other tissues. Samples were treated by an enzymatic trypsin solution or processed by the Medimachine II (MMII). The automated–mechanical and enzymatic disaggregation procedures have shown to work similarly in some tissues, which displayed comparable amounts of apoptotic/necrotic cells. However, cells obtained by the enzyme-free Medimachine II protocols show a better preservation lysosome and mitochondria labeling, whereas the enzymatic gentle dissociation appears to constantly induce a lower amount of intracellular ROS; nevertheless, lightly increased ROS can be recognized as a complimentary signal to promote cell survival. Therefore, MMII represents a simple, fast, and standardized method for tissue processing, which allows to minimize bias arising from the operator’s ability. Our study points out technical issues to be adopted for specific organs and tissues to obtain functional cells.
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Affiliation(s)
- Mariele Montanari
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, Italy; (M.M.); (S.B.); (C.C.); (P.A.); (S.C.); (W.B.); (D.L.); (G.P.); (S.P.)
| | - Sabrina Burattini
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, Italy; (M.M.); (S.B.); (C.C.); (P.A.); (S.C.); (W.B.); (D.L.); (G.P.); (S.P.)
| | - Caterina Ciacci
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, Italy; (M.M.); (S.B.); (C.C.); (P.A.); (S.C.); (W.B.); (D.L.); (G.P.); (S.P.)
| | - Patrizia Ambrogini
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, Italy; (M.M.); (S.B.); (C.C.); (P.A.); (S.C.); (W.B.); (D.L.); (G.P.); (S.P.)
| | - Silvia Carloni
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, Italy; (M.M.); (S.B.); (C.C.); (P.A.); (S.C.); (W.B.); (D.L.); (G.P.); (S.P.)
| | - Walter Balduini
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, Italy; (M.M.); (S.B.); (C.C.); (P.A.); (S.C.); (W.B.); (D.L.); (G.P.); (S.P.)
| | - Daniele Lopez
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, Italy; (M.M.); (S.B.); (C.C.); (P.A.); (S.C.); (W.B.); (D.L.); (G.P.); (S.P.)
- Department of Pure and Applied Sciences (DiSPeA), University of Urbino Carlo Bo, 61029 Urbino, Italy
| | - Giovanna Panza
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, Italy; (M.M.); (S.B.); (C.C.); (P.A.); (S.C.); (W.B.); (D.L.); (G.P.); (S.P.)
| | - Stefano Papa
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, Italy; (M.M.); (S.B.); (C.C.); (P.A.); (S.C.); (W.B.); (D.L.); (G.P.); (S.P.)
| | - Barbara Canonico
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, Italy; (M.M.); (S.B.); (C.C.); (P.A.); (S.C.); (W.B.); (D.L.); (G.P.); (S.P.)
- Correspondence:
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The influence of fixation of biological samples on cell count and marker expression stability in flow cytometric analyses. Cent Eur J Immunol 2021; 45:206-213. [PMID: 33456333 PMCID: PMC7792444 DOI: 10.5114/ceji.2020.95858] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 10/11/2019] [Indexed: 11/24/2022] Open
Abstract
The most common applications of flow cytometry (FC) include diagnostics of haemato-oncological disorders, based on analysis of bone marrow, peripheral blood (PB), or cerebrospinal fluid (CSF) samples. A proper diagnostic process requires standardisation in setting the optimal time frame between material collection and the assay. Unfortunately, this might be difficult to achieve in daily practice due to unintended shipment delays, which might compromise large-scale multicentre studies. Thus, material fixation should be considered as a solution. The most widely used fixative agents are: paraformaldehyde, TransFix®, Cyto-Chex®, and serum-containing media. In this review, we attempted to summarise the literature data on the influence of sample storage under different temperatures and times combined with different fixation conditions on the cell count and marker expression levels. Based on the findings of several extensive studies employing fixed PB samples, it can be concluded that the performance of particular fixative greatly depends on the analysed marker and specific PB cell population expressing a given antigen. Preservation of absolute cell count was usually better in Cyto-Chex®-fixed PB samples, whereas TransFix® tended to better stabilise marker expression levels. CSF-based studies reveal that both serum-containing media and TransFix® can prevent cellular loss and enhance FC-based detection of leptomeningeal localisations of haematological malignancies, the latter being more available and having longer shelf-life. As both cell count and marker expression level are the main determinants of quality of biological samples dedicated to FC analyses, it remains to be addressed by the investigators which is the fixative of choice for their specific research aims.
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Harrison D, Ward R, Bastow S, Parr A, Macro S, Wallace PK. Interlaboratory comparison of the TransFix®/EDTA Vacuum Blood Collection tube with the 5 mL Cyto-Chex® BCT. CYTOMETRY PART B-CLINICAL CYTOMETRY 2018; 96:496-507. [PMID: 30353647 DOI: 10.1002/cyto.b.21731] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 07/13/2018] [Accepted: 07/27/2018] [Indexed: 11/12/2022]
Abstract
BACKGROUND An interlaboratory study was performed to compare the performance of the 3 mL TransFix®/EDTA Vacuum Blood Collection Tube (TVT), with the 5 mL Cyto-Chex® BCT tube (BCT). Both devices are intended for collection and storage of whole blood specimens for immunophenotyping of leukocytes by flow cytometry for up to 14 days. METHODS One site in the United States and two in the United Kingdom tested samples from 10 HIV positive patients and four healthy subjects for a total of 42 samples. From each subject, three blood samples were collected: a BD 4 mL K3 EDTA Vacutainer (Vacutainer), a TVT, and a BCT. At all sites, samples were analyzed on a BD FACS Canto II flow cytometer for a full lymphocyte subset count within 6 h of collection (all devices) and on Day 11 and Day 15 (TVT and BCT only). Data obtained from the Vacutainer were used as the control data set with which TVT and BCT data were statistically compared. RESULTS AND CONCLUSIONS Statistical concordance was demonstrated for both devices in relation to cell absolute count recovery. For cell marker signal, both devices exhibited a significant decrease in mean fluorescence intensity (MFI) for the detection of lymphocyte subsets and their target markers. There was a marked increase in autofluorescence observed for BCT stabilized lymphocytes whereas values for the TVTs were comparable to the control. There were eight instances of statistical equivalence between the level of antibody autofluorescence observed in the control tube and the TVT across both patient cohorts, versus two for the BCT. © 2018 International Clinical Cytometry Society.
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Affiliation(s)
| | - Rosalie Ward
- Haematology Department, Royal Hallamshire Hospital, Sheffield, UK
| | - Sarah Bastow
- Pathology Department, Royal Sussex County Hospital, Brighton, UK
| | - Andrew Parr
- Pathology Department, Royal Sussex County Hospital, Brighton, UK
| | - Susan Macro
- Department of Flow and Image Cytometry, Roswell Park Cancer Institute, Buffalo, New York
| | - Paul K Wallace
- Department of Flow and Image Cytometry, Roswell Park Cancer Institute, Buffalo, New York
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Sympathoadrenal Activation is Associated with Acute Traumatic Coagulopathy and Endotheliopathy in Isolated Brain Injury. Shock 2018; 46:96-103. [PMID: 27206278 PMCID: PMC4978599 DOI: 10.1097/shk.0000000000000642] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Background: Acute coagulopathy after traumatic brain injury (TBI) involves a complex multifactorial hemostatic response that is poorly characterized. Objectives: To examine early posttraumatic alterations in coagulofibrinolytic, endothelial, and inflammatory blood biomarkers in relation to sympathetic nervous system (SNS) activation and 6-month patient outcomes, using multivariate partial least-squares (PLS) analysis. Patients and Methods: A multicenter observational study of 159 adult isolated TBI patients admitted to the emergency department at an urban level I trauma center, was performed. Plasma concentrations of 6 coagulofibrinolytic, 10 vascular endothelial, 19 inflammatory, and 2 catecholamine biomarkers were measured by immunoassay on admission and 24 h postinjury. Neurological outcome at 6 months was assessed using the Extended Glasgow Outcome Scale. PLS-discriminant analysis was used to identify salient biomarker contributions to unfavorable outcome, whereas PLS regression analysis was used to evaluate the covariance between SNS correlates (catecholamines) and biomarkers of coagulopathy, endotheliopathy, and inflammation. Results: Biomarker profiles in patients with an unfavorable outcome displayed procoagulation, hyperfibrinolysis, glycocalyx and endothelial damage, vasculature activation, and inflammation. A strong covariant relationship was evident between catecholamines and biomarkers of coagulopathy, endotheliopathy, and inflammation at both admission and 24 h postinjury. Conclusions: Biomarkers of coagulopathy and endotheliopathy are associated with poor outcome after TBI. Catecholamine levels were highly correlated with endotheliopathy and coagulopathy markers within the first 24 h after injury. Further research is warranted to characterize the pathogenic role of SNS-mediated hemostatic alterations in isolated TBI.
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González C, Esteban R, Canals C, Muñiz-Díaz E, Nogués N. Stabilization of Transfected Cells Expressing Low-Incidence Blood Group Antigens: Novel Methods Facilitating Their Use as Reagent-Cells. PLoS One 2016; 11:e0161968. [PMID: 27603310 PMCID: PMC5014343 DOI: 10.1371/journal.pone.0161968] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 08/15/2016] [Indexed: 11/27/2022] Open
Abstract
Background The identification of erythrocyte antibodies in the serum of patients rely on panels of human red blood cells (RBCs), which coexpress many antigens and are not easily available for low-incidence blood group phenotypes. These problems have been addressed by generating cell lines expressing unique blood group antigens, which may be used as an alternative to human RBCs. However, the use of cell lines implies several drawbacks, like the requirement of cell culture facilities and the high cost of cryopreservation. The application of cell stabilization methods could facilitate their use as reagent cells in clinical laboratories. Methods We generated stably-transfected cells expressing low-incidence blood group antigens (Dia and Lua). High-expresser clones were used to assess the effect of TransFix® treatment and lyophilization as cell preservation methods. Cells were kept at 4°C and cell morphology, membrane permeability and antigenic properties were evaluated at several time-points after treatment. Results TransFix® addition to cell suspensions allows cell stabilization and proper antigen detection for at least 120 days, despite an increase in membrane permeability and a reduction in antigen expression levels. Lyophilized cells showed minor morphological changes and antigen expression levels were rather conserved at days 1, 15 and 120, indicating a high stability of the freeze-dried product. These stabilized cells have been proved to react specifically with human sera containing alloantibodies. Conclusions Both stabilization methods allow long-term preservation of the transfected cells antigenic properties and may facilitate their distribution and use as reagent-cells expressing low-incidence antigens, overcoming the limited availability of such rare RBCs.
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Affiliation(s)
- Cecilia González
- Immunohematology Laboratory, Banc de Sang i Teixits, Barcelona, Spain
| | - Rosa Esteban
- Immunohematology Laboratory, Banc de Sang i Teixits, Barcelona, Spain
| | - Carme Canals
- Immunohematology Laboratory, Banc de Sang i Teixits, Barcelona, Spain
| | | | - Núria Nogués
- Immunohematology Laboratory, Banc de Sang i Teixits, Barcelona, Spain
- * E-mail:
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Letzkus M, Luesink E, Starck-Schwertz S, Bigaud M, Mirza F, Hartmann N, Gerstmayer B, Janssen U, Scherer A, Schumacher MM, Verles A, Vitaliti A, Nirmala N, Johnson KJ, Staedtler F. Gene expression profiling of immunomagnetically separated cells directly from stabilized whole blood for multicenter clinical trials. Clin Transl Med 2014; 3:36. [PMID: 25984272 PMCID: PMC4424390 DOI: 10.1186/s40169-014-0036-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 10/07/2014] [Indexed: 12/12/2022] Open
Abstract
Background Clinically useful biomarkers for patient stratification and monitoring of disease progression and drug response are in big demand in drug development and for addressing potential safety concerns. Many diseases influence the frequency and phenotype of cells found in the peripheral blood and the transcriptome of blood cells. Changes in cell type composition influence whole blood gene expression analysis results and thus the discovery of true transcript level changes remains a challenge. We propose a robust and reproducible procedure, which includes whole transcriptome gene expression profiling of major subsets of immune cell cells directly sorted from whole blood. Methods Target cells were enriched using magnetic microbeads and an autoMACS® Pro Separator (Miltenyi Biotec). Flow cytometric analysis for purity was performed before and after magnetic cell sorting. Total RNA was hybridized on HGU133 Plus 2.0 expression microarrays (Affymetrix, USA). CEL files signal intensity values were condensed using RMA and a custom CDF file (EntrezGene-based). Results Positive selection by use of MACS® Technology coupled to transcriptomics was assessed for eight different peripheral blood cell types, CD14+ monocytes, CD3+, CD4+, or CD8+ T cells, CD15+ granulocytes, CD19+ B cells, CD56+ NK cells, and CD45+ pan leukocytes. RNA quality from enriched cells was above a RIN of eight. GeneChip analysis confirmed cell type specific transcriptome profiles. Storing whole blood collected in an EDTA Vacutainer® tube at 4°C followed by MACS does not activate sorted cells. Gene expression analysis supports cell enrichment measurements by MACS. Conclusions The proposed workflow generates reproducible cell-type specific transcriptome data which can be translated to clinical settings and used to identify clinically relevant gene expression biomarkers from whole blood samples. This procedure enables the integration of transcriptomics of relevant immune cell subsets sorted directly from whole blood in clinical trial protocols.
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Affiliation(s)
- Martin Letzkus
- Biomarker Development, Novartis Institutes for BioMedical Research (NIBR), Basel, Switzerland
| | - Evert Luesink
- Biomarker Development, Novartis Institutes for BioMedical Research (NIBR), Basel, Switzerland
| | | | - Marc Bigaud
- Biomarker Development, Novartis Institutes for BioMedical Research (NIBR), Basel, Switzerland
| | - Fareed Mirza
- Scientific Capability Development, Pharma-Development, Novartis Pharma AG, Basel, Switzerland
| | - Nicole Hartmann
- Biomarker Development, Novartis Institutes for BioMedical Research (NIBR), Basel, Switzerland
| | | | - Uwe Janssen
- Miltenyi Biotec GmbH, Bergisch Gladbach, Germany
| | | | - Martin M Schumacher
- Biomarker Development, Novartis Institutes for BioMedical Research (NIBR), Basel, Switzerland
| | - Aurelie Verles
- Biomarker Development, Novartis Institutes for BioMedical Research (NIBR), Basel, Switzerland
| | - Alessandra Vitaliti
- Biomarker Development, Novartis Institutes for BioMedical Research (NIBR), Basel, Switzerland
| | - Nanguneri Nirmala
- Biomarker Development, Novartis Institutes for BioMedical Research (NIBR), Cambridge, MA, USA
| | - Keith J Johnson
- Biomarker Development, Novartis Institutes for BioMedical Research (NIBR), Cambridge, MA, USA
| | - Frank Staedtler
- Biomarker Development, Novartis Institutes for BioMedical Research (NIBR), Basel, Switzerland
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Enumeration of circulating fibrocytes for clinical use in asthma by an optimized single-platform flow cytometry assay. BBA CLINICAL 2014; 1:52-8. [PMID: 26673636 PMCID: PMC4633918 DOI: 10.1016/j.bbacli.2014.06.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 06/04/2014] [Accepted: 06/09/2014] [Indexed: 11/23/2022]
Abstract
Background Elevated numbers of circulating fibrocytes are associated with inadequately controlled asthma, poor response to available therapies, and increased risk of adverse outcomes. The lack of reliable and clinically-applicable assays precludes a proper evaluation of blood fibrocyte count as a prognostic biomarker in asthma. This report concerns the use of a multiparameter flow cytometry assay for the enumeration of fibrocytes in the whole blood. Methods Consenting fibrocyte donors were 19 patients with asthma well controlled by current treatment, 16 patients with treatment-resistant asthma, 9 patients with transiently uncontrolled asthma and 14 age-matched normal individuals. Blood sampling was performed once in patients with transiently uncontrolled asthma and twice, at an interval of one week, in the other subjects. The assay was performed in 100 μl of whole blood and involved a sequential gating strategy and absolute fibrocyte counting with a single instrument (single-platform assay). Results The quantification of circulating fibrocytes by this assay was analytically and clinically valid. In individuals with stable clinical conditions, the repeatability of blood fibrocyte counts over one week was good. The intraclass correlation coefficient was 0.939 and 96.88% of the total variability reflected on-average differences among the tested subjects. Stabilized blood samples could be stored at 4 °C for up to 96 h before processing. Conclusions The novel assay for the enumeration of fibrocytes in the whole blood is reliable and clinically applicable. General significance This report demonstrates the validity and reliability of the first optimized assay for the enumeration of circulating fibrocytes in multicenter clinical trials. Elevated blood fibrocyte count is an emerging prognostic biomarker in asthma. The lack of reliable, clinically-applicable assays precludes further evaluation. An optimized whole-blood single-platform flow cytometry assay is described here. The assay is analytically and clinically valid and provides reproducible measures. Stabilized blood samples can be stored for 96 h at 4 °C before processing.
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Key Words
- 7-AAD, 7-amino-actinomycin-D
- AF, Alexa Fluor
- Asthma
- BMC, blood mononuclear cell
- Biomarker
- CCC, concordance correlation coefficient
- CI, confidence interval
- COL1, type I collagen
- CT, threshold cycle
- Clinical outcome
- ET-1, endothelin-1
- FSC, forward scatter
- Fibrocyte enumeration
- Flow cytometry
- ICC, intraclass correlation coefficient
- MFI, mean fluorescence intensity
- PB, Pacific Blue
- SD, standard deviation
- SS, sum of squares
- SSC, side scatter
- Single-platform assay
- α-SMA, α-smooth muscle actin
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Ilmarinen P, Moilanen E, Kankaanranta H. Regulation of spontaneous eosinophil apoptosis-a neglected area of importance. J Cell Death 2014; 7:1-9. [PMID: 25278781 PMCID: PMC4167313 DOI: 10.4137/jcd.s13588] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 12/12/2013] [Accepted: 01/05/2013] [Indexed: 12/30/2022] Open
Abstract
Asthma is characterized by the accumulation of eosinophils in the airways in most phenotypes. Eosinophils are inflammatory cells that require an external survival-prolonging stimulus such as granulocyte macrophage-colony-stimulating factor (GM-CSF), interleukin (IL)-5, or IL-3 for survival. In their absence, eosinophils are programmed to die by spontaneous apoptosis in a few days. Eosinophil apoptosis can be accelerated by Fas ligation or by pharmacological agents such as glucocorticoids. Evidence exists for the relevance of these survival-prolonging and pro-apoptotic agents in the regulation of eosinophilic inflammation in inflamed airways. Much less is known about the physiological significance and mechanisms of spontaneous eosinophil apoptosis even though it forms the basis of regulation of eosinophil longevity by pathophysiological factors and pharmacological agents. This review concentrates on discussing the mechanisms of spontaneous eosinophil apoptosis compared to those of glucocorticoid- and Fas-induced apoptosis. We aim to answer the question whether the external apoptotic stimuli only augment the ongoing pathway of spontaneous apoptosis or truly activate a specific pathway.
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Affiliation(s)
- Pinja Ilmarinen
- The Immunopharmacology Research Group, School of Medicine University of Tampere and Tampere University Hospital, Tampere, Finland
| | - Eeva Moilanen
- The Immunopharmacology Research Group, School of Medicine University of Tampere and Tampere University Hospital, Tampere, Finland
| | - Hannu Kankaanranta
- The Immunopharmacology Research Group, School of Medicine University of Tampere and Tampere University Hospital, Tampere, Finland. ; Department of Respiratory Medicine, Seinäjoki Central Hospital, Seinäjoki, Finland and University of Tampere, Tampere, Finland
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Luchetti F, Canonico B, Arcangeletti M, Guescini M, Cesarini E, Stocchi V, Degli Esposti M, Papa S. Fas signalling promotes intercellular communication in T cells. PLoS One 2012; 7:e35766. [PMID: 22558220 PMCID: PMC3338457 DOI: 10.1371/journal.pone.0035766] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Accepted: 03/21/2012] [Indexed: 12/20/2022] Open
Abstract
Cell-to-cell communication is a fundamental process for development and maintenance of multicellular organisms. Diverse mechanisms for the exchange of molecular information between cells have been documented, such as the exchange of membrane fragments (trogocytosis), formation of tunneling nanotubes (TNTs) and release of microvesicles (MVs). In this study we assign to Fas signalling a pivotal role for intercellular communication in CD4+ T cells. Binding of membrane-bound FasL to Fas expressing target cells triggers a well-characterized pro-apoptotic signalling cascade. However, our results, pairing up flow cytometric studies with confocal microscopy data, highlight a new social dimension for Fas/FasL interactions between CD4+ T cells. Indeed, FasL enhances the formation of cell conjugates (8 fold of increase) in an early time-frame of stimulation (30 min), and this phenomenon appears to be a crucial step to prime intercellular communication. Our findings show that this communication mainly proceeds along a cytosolic material exchange (ratio of exchange >10, calculated as ratio of stimulated cells signal divided by that recorded in control cells) via TNTs and MVs release. In particular, inhibition of TNTs genesis by pharmacological agents (Latruculin A and Nocodazole) markedly reduced this exchange (inhibition percentage: >40% and >50% respectively), suggesting a key role for TNTs in CD4+ T cells communication. Although MVs are present in supernatants from PHA-activated T cells, Fas treatment also leads to a significant increase in the amount of released MVs. In fact, the co-culture performed between MVs and untreated cells highlights a higher presence of MVs in the medium (1.4 fold of increase) and a significant MVs uptake (6 fold of increase) by untreated T lymphocytes. We conclude that Fas signalling induces intercellular communication in CD4+ T cells by different mechanisms that seem to start concomitantly with the main pathway (programmed cell death) promoted by FasL.
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Affiliation(s)
- Francesca Luchetti
- Department of Earth, Life and Environmental Sciences, University of Urbino Carlo Bo, Urbino, Italy.
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