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Judge SJ, Murphy WJ, Canter RJ. Characterizing the Dysfunctional NK Cell: Assessing the Clinical Relevance of Exhaustion, Anergy, and Senescence. Front Cell Infect Microbiol 2020; 10:49. [PMID: 32117816 PMCID: PMC7031155 DOI: 10.3389/fcimb.2020.00049] [Citation(s) in RCA: 110] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 01/24/2020] [Indexed: 12/24/2022] Open
Abstract
There is a growing body of literature demonstrating the importance of T cell exhaustion in regulating and shaping immune responses to pathogens and cancer. Simultaneously, the parallel development of therapeutic antibodies targeting inhibitory molecules associated with immune exhaustion (such as PD-1, but also TIGIT, and LAG-3) has led to a revolution in oncology with dramatic benefits in a growing list of solid and hematologic malignancies. Given this success in reinvigorating exhausted T cells and the related anti-tumor effects, there are increasing efforts to apply immune checkpoint blockade to other exhausted immune cells beyond T cells. One approach involves the reinvigoration of “exhausted” NK cells, a non-T, non-B lymphoid cell of the innate immune system. However, in contrast to the more well-defined and established molecular, genetic, and immunophenotypic characteristics of T cell exhaustion, a consensus on the defining functional and phenotypic features of NK “exhaustion” is less clear. As is well-known from T cell biology, separate and distinct molecular and cellular processes including senescence, anergy and exhaustion can lead to diminished immune effector function with different implications for immune regulation and recovery. For NK cells, it is unclear if exhaustion, anergy, and senescence entail separate and distinct entities of dysfunction, though all are typically characterized by decreased effector function or proliferation. In this review, we seek to define these distinct spheres of NK cell dysfunction, analyzing how they have been shown to impact NK biology and clinical applications, and ultimately highlight key characteristics in NK cell function, particularly in relation to the role of “exhaustion.”
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Affiliation(s)
- Sean J Judge
- Division of Surgical Oncology, Department of Surgery, University of California, Davis, Sacramento, CA, United States
| | - William J Murphy
- Department of Dermatology, University of California, Davis, Sacramento, CA, United States.,Department of Medicine, University of California, Davis, Sacramento, CA, United States
| | - Robert J Canter
- Division of Surgical Oncology, Department of Surgery, University of California, Davis, Sacramento, CA, United States
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Fenzl L, Göbel TW, Neulen ML. γδ T cells represent a major spontaneously cytotoxic cell population in the chicken. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2017; 73:175-183. [PMID: 28377199 DOI: 10.1016/j.dci.2017.03.028] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 03/31/2017] [Accepted: 03/31/2017] [Indexed: 06/07/2023]
Abstract
Natural killer cells in the chicken are mainly confined to the intestine, while only small frequencies are detectable in spleen, lung and blood. Here, we compared the spontaneous cytotoxicity of lymphocytes isolated from blood, spleen and intestine using a flow cytometric based cytotoxicity assay. There was no spontaneous cytotoxicity detected in chicken blood preparations. In contrast, freshly prepared splenocytes exhibited a spontaneous cytotoxicity of up to 50% and intestinal epithelial lymphocytes of up to 85%. This cytotoxicity was observed against the RP9 but not against the chicken CU24 target cell line. The observed cytotoxicity was MHC unrestricted since B2B2 derived effector cells killed RP9 target cells (B2B15) equally well compared to MHC mismatched 2D8 targets (B19B19). The cytotoxicity of splenocytes was enhanced by preincubation with IL-2 or strongly increased with IL-2 plus IL-12. By cell sorting, we identified the CD8+γδ T cell subset as the major effectors, whereas both CD8-γδ T cells and CD8+αβ T cells had only low cytolytic potential. Within intestinal lymphocyte CD45+cells displayed cytotoxicity as well as sorted γδ T cells and NK cell. In conclusion, the chicken γδ T cells represent a major cytotoxic lymphocyte subset that can lyse target cells in a MHC unrestricted manner.
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Affiliation(s)
- Lisa Fenzl
- Institute for Animal Physiology, Department of Veterinary Sciences, University of Munich, Veterinärstrasse 13, 80539 Munich, Germany
| | - Thomas W Göbel
- Institute for Animal Physiology, Department of Veterinary Sciences, University of Munich, Veterinärstrasse 13, 80539 Munich, Germany.
| | - Marie-Luise Neulen
- Institute for Animal Physiology, Department of Veterinary Sciences, University of Munich, Veterinärstrasse 13, 80539 Munich, Germany
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Effects of surgery, general anesthesia, and perioperative epidural analgesia on the immune function of patients with non-small cell lung cancer. J Clin Anesth 2013; 25:255-62. [PMID: 23659826 DOI: 10.1016/j.jclinane.2012.12.007] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2012] [Revised: 12/04/2012] [Accepted: 12/07/2012] [Indexed: 02/03/2023]
Abstract
STUDY OBJECTIVE To assess preoperative and postoperative immune function in patients undergoing surgical resection of non-small cell lung cancer during general anesthesia and postoperative epidural analgesia. DESIGN Observational single-center study. SETTING University-affiliated academic center. PATIENTS 24 adult, ASA physical status 3 and 4 patients with stage 1, 2, or 3 non-small cell lung cancer. No study patient received preoperative chemotherapy or radiation. INTERVENTIONS Patients underwent thoracotomy with general anesthesia and postoperative epidural analgesia. MEASUREMENTS Bispectral index monitoring, sevoflurane requirements, and intraoperative transfusions were recorded. Total fentanyl consumption and pain (verbal numeric rating scale) were recorded 24 hours after surgery. Preoperative and 24-hour postoperative natural killer cell percentage and function and percentages of natural killer T cells, T helper cells (CD4+), and cytotoxic T lymphocytes (CD8+) were measured. Plasma concentrations of the TH1 cytokine interleukin-2 and interferon-gamma and the TH2 cytokines interleukin-4 were measured at the same time points. RESULTS The percentage (preoperative, 13.07 ± 9.81% vs postoperative, 9.6 ± 6.57%, P < 0.001) and function (preoperative, 31.61 ± 21.96%; postoperative, 13.61 ± 9.36%; P < 0.001) of natural killer cells was significantly decreased after surgery, but the percentage of natural killer T cells, T helper cells (CD4+), and cytotoxic T lymphocytes (CD8+) remained unchanged postoperatively; thus, the CD4/CD8 ratio remained unchanged. Postoperative plasma concentrations of the three cytokines were similar to preoperative levels; therefore, the TH1/TH2 ratio also remained unchanged. CONCLUSIONS Innate immunity is depressed in patients with non-small cell lung cancer after surgical resection, and immunity is not preserved by the use of postoperative epidural analgesia.
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Paillard C, Halle P, Tchirkov A, Confland C, Veyrat-Masson R, Quainon F, Perreira B, Rochette E, Pfeiffer M, Lang P, Deméocq F, Kanold J. NK cytotoxicity and alloreactivity against neuroblastoma cell lines in vitro: Comparison of Europium fluorometry assay and quantification by RT-PCR. J Immunol Methods 2012; 380:56-64. [DOI: 10.1016/j.jim.2012.03.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 02/13/2012] [Accepted: 03/29/2012] [Indexed: 10/28/2022]
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Hopkinson K, Williams EA, Fairburn B, Forster S, Flower DJ, Saxton JM, Pockley AG. A MitoTracker Green-based flow cytometric assay for natural killer cell activity: variability, the influence of platelets and a comparison of analytical approaches. Exp Hematol 2007; 35:350-7. [PMID: 17309815 DOI: 10.1016/j.exphem.2006.12.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2006] [Revised: 12/01/2006] [Accepted: 12/07/2006] [Indexed: 11/21/2022]
Abstract
OBJECTIVE A number of flow cytometric assays for natural killer (NK) cell cytotoxicity have been described, however, the relative merits of analytical approaches and the influence of platelets on measured responses have not been systematically evaluated. Information on the time-dependent variability in measured responses is also limited. MATERIALS AND METHODS Human peripheral blood mononuclear cells were obtained using Nycoprep 1.077, or Nycoprep 1.077 followed by Nycoprep 1.068 (to remove platelets), and incubated for 3 hours with MitoTracker Green (MTG)-labeled K562 cells. Cells were stained with propidium iodide (PI) and the proportions of viable and nonviable target cells (MTG(+)PI(-), MTG(+)PI(+)) were determined by flow cytometry using quadrant and polygonal region analysis. RESULTS Platelets inhibited NK cell cytotoxicity and the response was underestimated when the nonviable target cell population was not entirely enclosed within the nonviable target cell (upper right) flow cytometric quadrant. The variability in measured NK cell cytotoxic responses in samples obtained from five individuals on three occasions over a 3-week period was 28%, 24%, 26%, and 37%, and 19%, 23%, 27%, and 32% for the quadrant and region analyses (mean coefficient of variation at effector-to-target cell ratios of 100:1, 50:1, 25:1, and 12.5:1, respectively), and 24% and 20% when data were calculated as the area under the cytotoxic curve (AUCC). CONCLUSION Polygonal regions and the calculation of data as the AUCC appear to be the best approach. This study will be of value to investigators that are wishing to incorporate an NK cell cytotoxicity assay into their portfolio of experimental techniques.
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Affiliation(s)
- Kay Hopkinson
- Immunobiology Research Unit, University of Sheffield, Sheffield, UK
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Godoy-Ramirez K, Mäkitalo B, Thorstensson R, Sandström E, Biberfeld G, Gaines H. A novel assay for assessment of HIV-specific cytotoxicity by multiparameter flow cytometry. Cytometry A 2006; 68:71-80. [PMID: 16228974 DOI: 10.1002/cyto.a.20189] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND Assessment of CD8(+) T-cell activity is of significant importance for the evaluation of cellular immune responses to viral infections, especially in HIV. We present a new assay for the assessment of HIV-specific cytotoxicity by multiparameter flow cytometry. METHODS Target cells, pulsed with peptide pools (Gag or Nef), were stained with 5- (and -6)-carboxyfluorescein diacetate succinimidyl ester (CFSE), cultured with specific or nonspecific effector cells, and finally stained with propidium iodide (PI). Determination of cytolysis is based on the enumeration of viable target cells (CFSE(hi)PI(-)) in the test sample (target and specific effector cells) as compared with that of the viable target cells in the control sample (target and nonspecific effector cells). The (51)Cr-release assay and IFN-gamma ELISpot were performed by standard procedures. RESULTS A comparison with the Cr-release showed that the two assays were strongly correlated (r = 0.67; P < 0.001) but the sensitivity of the flow cytometric assay was significantly higher (P < 0.05), and the reproducibility good (CV, 7.7%). Good correlation was also found with the ELISpot assay (r = 0.66; P < 0.01). CONCLUSION This new assay provides both specific and sensitive results when employed for the detection of HIV-specific CTL and can be a valuable tool for the evaluation of cytolytic activity in vaccine trials or in HIV-infected subjects, especially if such responses are present at low levels.
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Affiliation(s)
- Karina Godoy-Ramirez
- Department of Immunology and Vaccinology, Swedish Institute for Infectious Disease Control, Sweden.
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Kasatori N, Ishikawa F, Ueyama M, Urayama T. A differential assay of NK-cell-mediated cytotoxicity in K562 cells revealing three sequential membrane impairment steps using three-color flow-cytometry. J Immunol Methods 2005; 307:41-53. [PMID: 16246359 DOI: 10.1016/j.jim.2005.09.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2004] [Revised: 07/05/2005] [Accepted: 09/06/2005] [Indexed: 11/25/2022]
Abstract
Annexin V and propidium iodide (PI) staining is a general technique for detecting apoptosis by flow-cytometry (FCM). The release of 2',7'-bis-(2-carboxyethyl)-5- (and-6)-carboxyfluorescein (BCECF), a non-lipophilic membrane-impermeable labeling dye, from the cytoplasm of target cells is an indicator of increased membrane permeability. This study aimed to devise a three-color FCM technique involving the BCECF-release parameter in addition to conventional Annexin V and PI staining for the analysis of target K562 cells undergoing cytotoxic/apoptotic processes mediated by natural killer (NK) cells. The results demonstrated the following step-wise process of membrane impairment: (1) initiation of Annexin V staining accompanied by increasing forward scatter (FSC) before BCECF-release, indicating membrane impairment without permeabilization by necrosis; (2) BCECF-release with decreasing FSC before PI influx; and (3) PI staining with the lowest FSC state. Therefore, the early stage of cytotoxicity/apoptosis conventionally defined by the flow-cytometric criteria of Annexin V staining before PI staining could be sub-divided into two stages before and after BCECF-release. Annexin-V staining in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis was also initiated without BCECF-release. Although the underlying mechanism of the transition process from stage 1 to stage 2 is still unknown, this FCM technique should be a useful tool for differential assays of target cells regarding the sequential processes of NK-induced cytotoxicity.
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Affiliation(s)
- Noriko Kasatori
- Department of Laboratory Medicine, Toho University School of Medicine, Ota-ku, Tokyo, Japan.
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Hassan ZM, Feyzi R, Sheikhian A, Bargahi A, Mostafaie A, Mansouri K, Shahrokhi S, Ghazanfari T, Shahabi S. Low molecular weight fraction of shark cartilage can modulate immune responses and abolish angiogenesis. Int Immunopharmacol 2005; 5:961-70. [PMID: 15829412 DOI: 10.1016/j.intimp.2005.01.006] [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: 10/05/2004] [Revised: 10/28/2004] [Accepted: 01/04/2005] [Indexed: 11/25/2022]
Abstract
Shark cartilage has proven to have inhibitory effects on angiogenesis. In this research, we studied the effects of shark cartilage on the immune system. Firstly, we isolated and purified a shark cartilage protein fraction with the most immunostimulatory effects. Our fraction was composed of two proteins with molecular weights of about 14 and 15 kDa. This fraction highly augments delayed-type hypersensitivity response against sRBC in mice, and decreases the cytotoxic activity of Natural Killer cells. Furthermore, intraperitoneal injection of this fraction to tumor-bearing mice could increase T-cell infiltration into the tumor, and decrease the tumor lesion size. Also, this fraction has strong inhibitory effect on HBMEC proliferation and migration in fibrin matrix. According to these results, we suppose that this fraction is a good candidate for further studies in cancer therapy.
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Affiliation(s)
- Zuhair M Hassan
- Department of Immunology, School of Medical Sciences, Tarbiat Modarres University, P.O. Box: 14115-111, Tehran, IR Iran.
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Hirsh M, Kaplan V, Dyugovskaya L, Krausz MM. Response of lung NK1.1-positive natural killer cells to experimental sepsis in mice. Shock 2005; 22:40-5. [PMID: 15201700 DOI: 10.1097/01.shk.0000129758.81361.45] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Natural killer cells (NKC) participate in the initiation of the immune response and coordination between innate and adaptive immune mechanisms. Their role in systemic inflammation induced by trauma or infection (sepsis) is still controversial. In the present study, lung NKC and their response to experimental sepsis were investigated. Mice were subjected to cecal ligation and puncture (CLP) to induce sepsis and acute lung injury (ALI). Animals were sacrificed 1, 4, and 7 days postoperatively, and lung histopathology, pulmonary vascular permeability, and inflammatory cells accumulation were assessed. On day 4, parameters of ALI were most prominent, and lung NK1.1+CD3- cells were isolated and studied by flow cytometry. Although CLP did not change the absolute number of lung NKC (2.47 +/- 0.52 x 10(5)/lung compared with 2.97 +/- 0.27 x 10(5)/lung in the sham group), the peak of the CLP-induced ALI was associated with severe dysfunction of lung NKC. Cell cytotoxicity decreased to 25.1 +/- 2.4% (P = 0.002), and percentage of perforin-positive NKC to 2.7 +/- 0.5% (P = 0.03). Cytokine profile of lung NK1.1+CD3- cells was prominently changed. The percentage of IFN-gamma-positive cells decreased to 19.7 +/- 5.7% (P = 0.047), but TNF-alpha-positive cells grew to 26.7 +/- 3.3% (P = 0.02). In summary, severe CLP-induced dysfunction of lung NK1.1+CD-3 cells was demonstrated. This may influence the outcome of the animals during sepsis and acute lung damage.
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Affiliation(s)
- Mark Hirsh
- Department of Surgery A and Laboratory for Shock and Trauma Research, Rambam Medical Center, Haifa, Israel.
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Olin MR, Hwa Choi K, Lee J, Molitor TW. γδ T-lymphocyte cytotoxic activity against Mycobacterium bovis analyzed by flow cytometry. J Immunol Methods 2005; 297:1-11. [PMID: 15777926 DOI: 10.1016/j.jim.2004.10.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2004] [Revised: 10/08/2004] [Accepted: 10/12/2004] [Indexed: 11/22/2022]
Abstract
Gamma Delta (gammadelta) T lymphocytes contain the unique capability of responding to pathogens in both an innate and acquired immune response. Previously, gammadelta lymphocytes have been reported to respond to Mycobacteria tuberculosis determined by proliferation and IFN-gamma production. Unlike alpha beta (alphabeta) lymphocytes, gammadelta lymphocytes constitutively express a natural killer receptor providing gammadelta lymphocytes the capability for innate cytolytic functions. A new cytolytic assay by flow cytometry was reported capable of determining natural killer activity using K562 cells as targets without the need for radioactive materials. The objectives of this study were to first apply the flow cytometer-based assay to assess gammadelta lymphocytes natural killer activity following animal vaccination with Mycobacterium bovis Bacillus Calmette-Guerin (BCG). Secondly, to optimize the flow cytometer assay in order to detect antigen specific cytolytic activity to mycobacterium and to compare the cytolytic activity of gammadelta lymphocytes to CD-8 lymphocytes. gammadelta lymphocytes increased in NK activity (P=0.012) following animal vaccination with M. bovis BCG. Both innate (P=0.02) and acquired antigen-specific cytolytic activity (P=0.04) increased following incubation with M. bovis-infected monocytes. In conclusion, flow cytometric-based assay is a sensitive and reliable tool to determine cytolytic activity of gammadelta T-lymphocytes against mycobacterium.
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Affiliation(s)
- Michael R Olin
- Clinical and Population Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA
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Zimmermann SY, Esser R, Rohrbach E, Klingebiel T, Koehl U. A novel four-colour flow cytometric assay to determine natural killer cell or T-cell-mediated cellular cytotoxicity against leukaemic cells in peripheral or bone marrow specimens containing greater than 20% of normal cells. J Immunol Methods 2005; 296:63-76. [PMID: 15680151 DOI: 10.1016/j.jim.2004.10.014] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2004] [Revised: 09/15/2004] [Accepted: 10/25/2004] [Indexed: 11/25/2022]
Abstract
To be able to determine the cytotoxic activity of NK cells or T cells against leukaemic cells in patient samples containing >20% of normal peripheral blood cells, we have developed a four-colour flow cytometric cytotoxicity assay. The assay is based on differential immunostaining of both leukaemic cells and effector cells in combination with propidium iodide (PI). The cytometer is set for measuring the fluorescence of the monoclonal antibody (mAb) bound fluorochromes, with moderate overcompensation of the third and fourth fluorescence signals. PI-positive events were excluded from analysis by their characteristic uncompensated signal on these two detectors. Thus, all four fluorescence ranges can be used for detection of mAb-derived signals and this allows discrimination between various populations contained in effector and target cell samples. The cytotoxic activity in our assay is calculated by the absolute loss of vital leukaemic cells. For this purpose, fluorescent beads are included as an internal standard. When calculating the effector concentrations after coculture, characteristic changes can be seen which yield additional information about the presence of cytotoxic activity and the active effector cell subset. With this assay, we present a versatile tool that combines minimum cell manipulation before coculture with maximum information from a sample. The assay is suitable for the analysis of complex samples with regard to different cell subsets, their decrease or increase, and conjugate formation.
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Affiliation(s)
- Stefanie-Yvonne Zimmermann
- Laboratory for Stem Cell Transplantation and Immunotherapy, Paediatric Haematology, Oncology and Haemostaseology, Johann Wolfgang Goethe-Universität, Theodor-Stern-Kai 7, Frankfurt am Main, Germany.
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Kastrukoff LF, Lau A, Wee R, Zecchini D, White R, Paty DW. Clinical relapses of multiple sclerosis are associated with 'novel' valleys in natural killer cell functional activity. J Neuroimmunol 2004; 145:103-14. [PMID: 14644036 DOI: 10.1016/j.jneuroim.2003.10.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Natural killer (NK) cells are implicated in the pathogenesis of multiple sclerosis (MS). Nine relapsing-remitting MS (RRMS) patients along with age, sex, and NK responder status matched controls were studied serially. Although the average NK cell functional activity (FA) was not significantly different between both groups, four clinical relapses in RRMS patients were associated with the development of 'novel' valleys in FA. These valleys are of greater depth and duration than cyclical valleys observed in both RRMS and controls, precede the onset of clinical attacks, and are observed in RRMS but not controls. In both RRMS and controls, cyclical peaks and valleys in FA are determined by the number of CD33+, CD3-CD56+, and to a lesser extent CD3+CD56+ cells capable of binding targets and inducing cell-mediated cytotoxicity (CMC). In contrast, 'novel' valleys in FA result from a reduction in the ability of CD3-CD56+ bound to targets to induce CMC. The results suggest that RRMS patients are at greater risk for clinical relapses during 'novel' valleys in FA. Furthermore, these valleys are the result of cells with a NK cell phenotype being unable to deliver a 'lethal' hit to targets.
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Affiliation(s)
- Lorne F Kastrukoff
- Department of Medicine, Division of Neurology, University of British Columbia, Vancouver Hospital & HSC, 2211 Wesbrook Mall, Vancouver, BC, Canada V6T-1Z3.
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Hassan ZM, Yaraee R, Zare N, Ghazanfari T, Sarraf Nejad AH, Nazori B. Immunomodulatory affect of R10 fraction of garlic extract on natural killer activity. Int Immunopharmacol 2003; 3:1483-9. [PMID: 12946445 DOI: 10.1016/s1567-5769(03)00161-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Naturally occurring modulators of carcinogenesis, including dietary compounds, can either stimulate or inhibit cancer development. Mechanisms responsible for these effects are unknown. Garlics used in this study were freshly prepared, and their effectiveness in augmenting natural killer (NK) activity was evaluated. Administration of 20 mg/kg produced an optimum augmentation of NK activity. A glycoprotein with MW of about 14 kDa was isolated from garlic extract and its activity was assessed. It could induce NK augmentation against K562 tumor cell line. In vivo studies also confirmed that Fraction Residue 10 (R10) of garlic extract partially purified by ultra filtration and further purified by chromatography could induce a resistance to the growth of spontaneous mammary carcinoma in Balb/c mice. NK cytotoxic activities were evaluated by flowcytometry.
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Affiliation(s)
- Zuhair M Hassan
- Department of Immunology, School of Medical Sciences, Tarbiat Modares University, Tehran, I.R., Iran.
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Wang Y, Korkeamäki M, Vainio O. A novel method to analyze viral antigen-specific cytolytic activity in the chicken utilizing flow cytometry. Vet Immunol Immunopathol 2003; 95:1-9. [PMID: 12969631 DOI: 10.1016/s0165-2427(03)00109-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
In order to overcome some of the main drawbacks that have emerged in the conventional assays for cytotoxic T-lymphocytes (CTLs) in the chicken, a novel approach to analyze viral antigen-specific cytolytic activity utilizing flow cytometry was developed. In this method, the target cells were distinguished from the effector cells by pre-labelling them with a fluorescent dye PKH67. Cell death was detected with propidium iodide which labels the DNA of damaged cells. Flow cytometric assay also enables phenotyping of the effector cells by direct or indirect immunofluorescence staining of lymphocyte surface molecules. The results showed that specific cytotoxic T cells were observed in the blood of chickens primed with fixed avian reticuloendotheliosis virus strain T transformed MHC-compatible B cells. Phenotypic analysis of the effector cells from blood demonstrated CTL activity both in CD8+ and CD4+ T cell populations and the majority CTLs were TCR2+ cells.
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Affiliation(s)
- Yongqiang Wang
- Department of Medical Microbiology, Turku Immunology Centre, Turku University, Kiinamyllynkatu 13, FIN-20520 Turku, Finland.
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Dyugovskaya L, Hirsh M, Ginsburg H. Phenotypic profile and functional characterization of rat lymph node-derived gammadelta T cells: implication in the immune response to cytomegalovirus. Immunology 2003; 108:129-36. [PMID: 12562320 PMCID: PMC1782877 DOI: 10.1046/j.1365-2567.2003.01568.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Gammadelta T cells are unique, and their localization at sites of infection is considered critical in immune defence. We demonstrate the accumulation of gammadelta T cells in rat regional popliteal lymph nodes (PLNi) starting 2 days after inoculation of cytomegalovirus (CMV) into the footpad. Early-appearance PLNi gammadelta T cells significantly inhibited plaque development and the spread of CMV infection. These gammadelta T cells were negative for CD4 and CD8beta receptors, proliferated in response to interleukin-2 (IL-2) and contained high levels of interferon-gamma (IFN-gamma), the appearance of which correlated with the curing of fibroblasts from virus infection. The addition of anti-IFN-gamma abolished the ability of fibroblast monolayers to be cured from CMV infection. In contrast, this protection was not abolished by the addition of anti-rat IL-2 or anti-rat TNF-alpha, or by the depletion of NKR-P1-bearing cells within gammadelta T cells. In addition, the present study shows that while gammadelta T cells derived from naive and CMV-infected rats are able to kill both YAC-1 targets and CMV-infected syngeneic fibroblasts in vitro, only the latter are able to clear CMV-infected fibroblast monolayers. Finally, our data suggest that the expression of NKR-P1 by gammadelta T cells is critical for cytotoxicity, but its contribution to the curing from CMV infection was limited.
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Affiliation(s)
- Larissa Dyugovskaya
- Department of Immunology, The Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
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Wang YY, Zheng XX. A flow cytometry-based assay for quantitative analysis of cellular proliferation and cytotoxicity in vitro. J Immunol Methods 2002; 268:179-88. [PMID: 12215386 DOI: 10.1016/s0022-1759(02)00190-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A novel method based on flow cytometry (FCM), which can count the number of detected cells, has been developed for the evaluation of cellular proliferation and cytotoxicity in vitro. It provides a tool that directly counts cell number without being influenced by the metabolic state of the cells, discriminates target cells from effector cells in cell-mediated cytotoxicity assay, and with less treatment step and free radioactivity. In this paper, we have prepared the PG cells (a highly metastatic human lung cancer cell line) and peripheral blood lymphocytes (PBL) with various concentrations and ratios of concentration to validate the method. The results were compared with MTT (3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyl tetrazolium bromide) assay and the regression analysis results showed that this method worked very well. We have also used this method to evaluate mitogen-induced proliferation and cytotoxicity. The results indicated that this method might yield high sensitivity and reliability.
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Affiliation(s)
- Yan-Yi Wang
- Department of Biomedical Engineering, Zhejiang University (Yuquan Campus), Hangzhou 310027, PR China
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Höppner M, Luhm J, Schlenke P, Koritke P, Frohn C. A flow-cytometry based cytotoxicity assay using stained effector cells in combination with native target cells. J Immunol Methods 2002; 267:157-63. [PMID: 12165437 DOI: 10.1016/s0022-1759(02)00167-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Flow-cytometry based assays for cellular cytotoxicity have established themselves widely over the last years. Discrimination of target and effector cells is critical for such assays. If scatter properties are not informative, the standard approach until now has been to label the target cells with a suitable fluorescent dye. However, this cannot be applied to a number of experimental settings, e.g. if one effector cell type is tested against several target cells, or if target cells do not incorporate the dye properly. Therefore, our goal was to develop a protocol based on the labelling of effector cells. For this purpose, we came around to using a membrane dye, DIOC18, which is not commonly used for flow-cytometric applications. This dye showed very stable membrane integration properties that allowed long-term coincubation periods (24 h) without leakage to neighbouring cells. The vitality and cytotoxic activity of the effector cells were not altered by staining. For the detection of dead cells, the intercalating DNA-dye 7-AAD was used. The spectral emission wavelengths of this combination also enable the additional use of PE-conjugated antibodies to surface antigens in three-color cytometry devices. Cytotoxicity values obtained by our protocol were highly correlated with values obtained by the chromium release assay at different E/T ratios and using several target cell lines. All in all, we present here an easy to handle protocol, which enables the precise determination of cellular cytotoxicity in various experimental settings.
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Affiliation(s)
- Maike Höppner
- Institute of Immunology and Transfusion Medicine, University of Lübeck School of Medicine, Ratzeburger Allee 160, Germany
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18
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Baker EJ, Ichiki AT, Day NE, Andrews RB, Bamberger EG, Lozzio CB. Simultaneous flow cytometric measurement of K-562 megakaryocytic differentiation and CD56+ large granular lymphocyte cytotoxicity. J Immunol Methods 2001; 253:37-44. [PMID: 11384667 DOI: 10.1016/s0022-1759(01)00373-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
K-562 cells have the capacity to undergo multi-lineage differentiation, which may be crucial to their ability to serve as target reservoirs for CD56+ large granular lymphocytes (LGL). Conventional techniques using chromium release assays to measure lymphocyte-mediated cytotoxicity suffer from disadvantages, including radioactive contamination and the inability to simultaneously determine K-562 and/or CD56+ lymphocyte phenotypes. We illustrate here a three-color flow cytometric method providing for the simultaneous evaluation of K-562-CD56+ LGL binding, K-562 cell viability, and the status of K-562 cell differentiation. Phorbol 12-myristate 13-acetate (PMA) engenders megakaryocytic differentiation in K-562 cell populations, as measured by presentation of the beta(3) integrin (gpIIIa, CD61), while maintaining a negative expression of MHC-I and MHC-II molecules. Using the auto-fluorescence of K-562 cells, flow cytometry can be used to demonstrate a significant decrease in CD56+ LGL activity against K-562 cells in populations pre-incubated with PMA. The capacity of three-color flow cytometry to measure lymphocyte-target cell binding and cell death kinetics, while simultaneously determining target cell phenotype, permits the specific localization of CD61-expressing K-562 cells to areas inconsistent with CD56+ LGL-mediated patterns of lysis.
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Affiliation(s)
- E J Baker
- Department of Medical Biology, Graduate School of Medicine, University of Tennessee Medical Center at Knoxville, 1924 Alcoa Highway, 37920, Knoxville, TN, USA
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19
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Lee-MacAry AE, Ross EL, Davies D, Laylor R, Honeychurch J, Glennie MJ, Snary D, Wilkinson RW. Development of a novel flow cytometric cell-mediated cytotoxicity assay using the fluorophores PKH-26 and TO-PRO-3 iodide. J Immunol Methods 2001; 252:83-92. [PMID: 11334968 DOI: 10.1016/s0022-1759(01)00336-2] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A flow cytometric (FCM) assay has been developed for the determination of cell-mediated cytotoxicity (CMC). In the assay, the target tumour cell population was labelled with a membrane dye, PKH-26, prior to incubation with splenocyte effector cells. Cell death within the target population was assessed by the addition of the viability probe TO-PRO-3 iodide (TP3) and analysed by flow cytometry. The extent of cytotoxicity was determined by the relative number of live target cells labelled with PKH-26 only and dead, permeabilised cells labelled with both PKH-26 and TP3. This CMC method allows the analysis to be conducted on a single cell basis and overcomes the need for radiochemicals. This communication indicates that the FCM assay is an accurate and reproducible experimental system capable of analysing natural killer (NK) cell and antibody-dependent cell-mediated cytotoxicity. The procedure is comparable to the chromium release assay. We believe that this is one of the first demonstrations of an FCM-based antibody-dependent cell-mediated cytotoxicity (ADCC) assay.
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Affiliation(s)
- A E Lee-MacAry
- Applied Development Laboratory, Imperial Cancer Research Technology (ICRT), Dominion House, St. Bartholomew's Hospital, EC1A 7BE, London, UK
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20
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Piriou L, Chilmonczyk S, Genetet N, Albina E. Design of a flow cytometric assay for the determination of natural killer and cytotoxic T-lymphocyte activity in human and in different animal species. CYTOMETRY 2000; 41:289-97. [PMID: 11084614 DOI: 10.1002/1097-0320(20001201)41:4<289::aid-cyto7>3.0.co;2-5] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND The most common assay used to detect natural killer (NK) and cytotoxic T-lymphocyte (CTL) activity is the (51)Cr release assay. The numerous disadvantages of this method led us to evaluate cytotoxicity functions by flow cytometry. We described a flow cytometric assay to assess NK and CTL activity from different species. METHODS This assay is based on a dual fluorescent staining of target cells. The dye, DIOC18((3)) (3, 3'-dioctadecyloxacarbocyanine perchlorate), is used to stain the membrane of different target cells. Propidium iodide (PI) is used to label dead target and effector cells. This labeling allows a clear discrimination between both cell populations. RESULTS A good correlation was observed between the percentage of target lysis and the effector-to-target cell (E/T) ratios with human and porcine peripheral blood mononuclear cells (PBMC) as effector cells. The flow cytometric assay was shown to be as sensitive and as reliable as the (51)Cr release performed with human cells. The assay was also applied successfully to measure NK cell activity in other animal species (pig, rabbit, hen, and mouse) and to measure murine CTL activity against the influenza virus. CONCLUSIONS We provide evidence that the flow cytometric assay using DIOC18((3)) is highly reproducible and is suitable to measure different types of cell cytotoxicity.
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Affiliation(s)
- L Piriou
- Agence Française de Sécurité Sanitaire des Aliments, Unité de Virologie et Immunologie Porcines, Ploufragan, France.
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21
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Abstract
A flow cytometer can quickly perform numerous quantitative, sensitive measurements on each individual cell within a large, heterogeneous population. The modern commercially available analytical instruments, which can be found in most hospitals, pathology laboratories, and cell biology research laboratories in the industrially developed countries, can now routinely measure fluorescence simultaneously at four different wavelengths, in addition to light scatter in two directions, at rates of thousands of cells per second. Thus, flow cytometry provides a powerful and versatile approach to the measurement of cell death and cell killing. However, it is important to stress that the biological nature of the phenomenon under investigation will determine which assay is appropriate, and at what stage in the process of cell killing it should be applied. This consideration is particularly important in the study of drug- or cell-mediated cytotoxicity.
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Affiliation(s)
- M A King
- Department of Clinical Immunology, Pacific Laboratory Medical Services, Royal North Shore Hospital, 2065, St. Leonards, NSW, Australia.
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22
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Godoy-Ramirez K, Franck K, Gaines H. A novel method for the simultaneous assessment of natural killer cell conjugate formation and cytotoxicity at the single-cell level by multi-parameter flow cytometry. J Immunol Methods 2000; 239:35-44. [PMID: 10821945 DOI: 10.1016/s0022-1759(00)00161-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
A flow cytometric assay for the combined measurement of cell-mediated cytotoxicity and conjugate formation has been developed. Cytolysis is detected by propidium iodide uptake. Target cells, effector cells and conjugates between targets and effectors are separated by post-culture immunophenotyping and their scatter profiles. Pre-assay staining of cells is thus not required. Each cluster of cells can be further examined at the single-cell level by simultaneously performed additional immunophenotyping. Two applications were established: the assessment of NK cell activity against K562 cells and the evaluation of LAK cell cytotoxicity against both K562 and Daudi cells. A comparison with the standard 51Cr release assay for the detection of NK cytotoxicity showed that the two assays were strongly correlated, but the sensitivity of the flow cytometric assay was significantly higher.
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Affiliation(s)
- K Godoy-Ramirez
- Swedish Institute for Infectious Disease Control/Karolinska Institutet, Solna, Sweden.
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23
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Sell DR, Primc M, Schafer IA, Kovach M, Weiss MA, Monnier VM. Cell-associated pentosidine as a marker of aging in human diploid cells in vitro and in vivo. Mech Ageing Dev 1998; 105:221-40. [PMID: 9862232 DOI: 10.1016/s0047-6374(98)00090-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Cellular aging is characterized by alterations at both the morphological and molecular levels, some of which are decreased mitotic rate, increased cytoplasmic vacuolization, and changes in intrinsic cellular constituents (Stanulis-Praeger, 1987. Mech. Ageing Dev. 38, 1-48). In the present investigation, glycoxidation is studied as a marker for cellular aging by measuring cell-associated pentosidine levels in human skin fibroblasts as a function of replicative life span and in human peripheral blood T lymphocytes as a function of chronological age. Fibroblasts were isolated from culture by detachment/centrifugation while lymphocytes were isolated from blood by a Ficoll-Paque/Lympho-Kwik T-Cell Prep technique. Pentosidine levels were measured in acid-hydrolyzed cell pellet suspensions by high-pressure liquid chromatography. Results show that pentosidine was detected in early and late cultured reticular and papillary fibroblasts. Pentosidine, expressed as either protein, DNA, or cell number, significantly (P < 0.0006) increased with in vitro passage and was significantly (P < 0.01) related to cell proliferation as measured by cell density and cell doublings per day during culture. Cell-associated pentosidine was measured in T lymphocytes isolated from healthy, diabetic, and uremic individuals. In healthy controls, levels significantly (P < 0.0003) increased with age. In uremic individuals, a large variation was observed with many values above the 95% confidence intervals determined for controls. Since a previous study showed that plasma pentosidine in healthy subjects does not increase with age, these results suggest that cellular turnover perhaps coupled to a deterioration in cellular anti-glycoxidation defensive mechanisms play a substantial role in explaining increased pentosidine concentrations during cellular aging.
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Affiliation(s)
- D R Sell
- Institute of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA
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24
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De Guise S, Ross PS, Osterhaus AD, Martineau D, Béland P, Fournier M. Immune functions in beluga whales (Delphinapterus leucas): evaluation of natural killer cell activity. Vet Immunol Immunopathol 1997; 58:345-54. [PMID: 9436277 DOI: 10.1016/s0165-2427(97)00035-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Natural killer (NK) activity, an important non-specific defense mechanism against viral infections and tumors, was demonstrated in beluga whales using two different methods: 51Cr release and flow cytometry. Using the 51Cr release assay, NK activity in belugas was shown to be higher against K-562 than against YAC-1 cell lines. Moreover, it was enhanced by the addition of human recombinant interleukin-2 with both cell lines. NK activity evaluated by flow cytometry in the peripheral blood of eight belugas increased when the effector:target cell (E:T) ratio increased, and averaged 13.9% +/- 3.8% (range 9.9% to 17.8%) at an E:T ratio of 100:1. While NK activity could be readily detected using both methods, the lack of radio-isotopes and related laboratory room make the flow cytometric method a viable and safe alternative. The evaluation of this function in cetaceans could lead to a better understanding of the early events that lead to viral epizootics in populations of marine mammals in different parts of the world, as well as to the high prevalence of neoplasms in St. Lawrence beluga whales.
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Affiliation(s)
- S De Guise
- TOXEN, Université du Québec à Montréal, Canada
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25
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Salmaggi A, Dufour A, Silvani A, Ciusani E, Nespolo A, Boiardi A. Intrathecal immunotherapy in CNS tumors disseminating via CSF: preliminary evaluation using different treatment schedules. ITALIAN JOURNAL OF NEUROLOGICAL SCIENCES 1996; 17:267-76. [PMID: 8915757 DOI: 10.1007/bf01997785] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Eight patients affected by central nervous system tumours disseminating via cerebrospinal fluid received rIL-2 immunotherapy according to three different protocols involving intrathecal administration followed or not by systemic infusion. Immunological monitoring included serial evaluation of CSF leukocytes, CSF and peripheral blood CD3-CD56+ cells, and NK activity. The most marked rise in CSF leukocyte levels was induced by daily intrathecal rIL2 administration, which also induced increased PB NK activity. Systemic rIL2 infusion following intrathecal treatment maintained a high percentage of CSF CD3-CD56+ cells, but not CSF leukocytes at high levels. Clinical conditions improved after treatment in two patients, worsened in one and remained substantially unchanged in the remaining five. The side effects of intrathecal rIL2 treatment included fever, confusion, and seizures, and there were marked interindividual variations in the immunological response.
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Affiliation(s)
- A Salmaggi
- Istituto Nazional Neurologico, C. Besta, Milano, Italy
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26
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Reno F, Luchetti F, Vitale M, Gregorini A, Valentini M, Papa S. Sorting of cells from different cell cycle phases using surface antigen expression. ACTA ACUST UNITED AC 1996. [DOI: 10.1007/bf00122159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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27
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Zaccaro L, Falcone ML, Silva S, Bigalli L, Cecchettini A, Giorgi F, Malvaldi G, Bendinelli M. Defective natural killer cell cytotoxic activity in feline immunodeficiency virus-infected cats. AIDS Res Hum Retroviruses 1995; 11:747-52. [PMID: 7576935 DOI: 10.1089/aid.1995.11.747] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Flow cytometry has been employed to study NK cell cytotoxic activity in cats infected with feline immunodeficiency virus. The results show that animals infected for 12 months or more have decreased levels of NK cell cytotoxic activity in their blood. The impairment could not be overcome by in vitro treatment of effector cells with interleukin 2. Additional results suggest that the NK cells of infected cats are defective, in that they are still able to bind to target cells but have a reduced ability to kill them.
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Affiliation(s)
- L Zaccaro
- Centro Retrovirus, Università di Pisa, Italy
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28
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Manogaran PS, Kausalya S, Pande G. Flow cytometric measurement of NK cell immunoconjugates by pulse width processing. CYTOMETRY 1995; 19:320-5. [PMID: 7796696 DOI: 10.1002/cyto.990190406] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Pulse width analysis, in flow cytometry, has been widely used for optimal cell size resolution in cell kinetics analysis. Pulses, generated by scattered light or fluorescence of cells, are electronically analyzed for their height and width. The information generated from these two properties of the pulses is utilized to distinguish signals from single cells vs. signals from cell clumps or aggregates. Pulse width, unlike pulse height, is more sensitive to differences in cell diameter, and therefore can discriminate very small differences in it, which pulse height cannot. We have exploited this property of pulse widths to measure immunoconjugates between NK cells and their targets. Discrimination of the free target cells from the conjugated ones is possible by the pulse widths of only light scatter signals, both forward and/or orthogonal. This resolution was not obtained if pulse height of the same signals was visualized. Using this resolution it was possible to distinguish single cells from the aggregates between target and effector cells. We propose that this is a better method for distinguishing conjugates than the method in which prior vital staining of cells is used.
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Affiliation(s)
- P S Manogaran
- Centre for Cellular and Molecular Biology, Hyderabad, India
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29
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Flieger D, Gruber R, Schlimok G, Reiter C, Pantel K, Riethmüller G. A novel non-radioactive cellular cytotoxicity test based on the differential assessment of living and killed target and effector cells. J Immunol Methods 1995; 180:1-13. [PMID: 7897241 DOI: 10.1016/0022-1759(94)00293-6] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Monocyte/macrophage-mediated cytotoxicity and antibody-dependent cellular cytotoxicity (ADCC) are slow processes, requiring cocultivation of effector and target cells for up to several days. Because of the high spontaneous release and possible reutilization of isotopic labels, the conventional radioactive release assays are unsuited for measuring long term cytotoxicity. We developed a non-radioactive flow cytometric assay for the quantitative analysis of cell-mediated cytotoxicity. Because dead cells can dissolve and disappear during the incubation period (lysis, phagocytosis), we determined the absolute numbers of living cells in the well. Prior to incubation the effector cells are stained with the red lipophilic fluorescent dye PKH26 and the target cells with the green fluorescent dye PKH2. At the end of the incubation (1-6 days) a defined number of bright fluorescent cell standards and propidium iodide for staining of dead cells was added to each well. Using flow cytometric analysis, we determined the ratio of targets to standards and calculated the absolute target cell number by multiplication with the known number of standards added. The main advantages of the assay are the possibility of extended incubation periods, the avoidance of radioactivity and its potential applicability to autologous culture systems, where effector and tumor cells are derived from the same patient. The assay opens new avenues for preclinical testing of tumor therapeutics such as monoclonal antibodies and/or cytokines.
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Affiliation(s)
- D Flieger
- Institute for Immunology, University of Munich, Germany
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30
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Salmaggi A, Dufour A, Silvani A, Ciusani E, Nespolo A, Boiardi A. Immunological fluctuations during intrathecal immunotherapy in three patients affected by CNS tumours disseminating via CSF. Int J Neurosci 1994; 77:117-25. [PMID: 7989157 DOI: 10.3109/00207459408986024] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The immunological therapy of cancer has been proposed in a number of neoplasms (Borden, Sondel, 1989; Foon, 1989; Rosenberg, 1992) and has recently been adopted in the treatment of Central Nervous System (CNS) tumors in combination with conventional surgical and radiotherapeutical approach. In this context, loco-regional administration of immunomodulating agents (for instance in post-surgical cavity) allows to achieve much higher in situ concentrations than by systemic route. Since these treatments have potential adverse effects, careful assessment of clinical and immunological parameters in phase I trials is needed. CNS tumors disseminating via Cerebrospinal Fluid (CSF) pathways offer a stimulating opportunity for intrathecal immunotherapy. In this context, alpha-IFN and IL2 (alone or in combination with LAK cells) have been employed either loco-regionally or intrathecally (Merchant, Mc Vicar, Merchant & Young, 1992; Schiller, Hank, Storer, Borchert, Moore, Albertini, Bechhofer, Wesley, Brown, Bastin & Sondel, 1993). The rationale for the use of both these substances includes the known anti-tumor action of alpha-IFN (Mahaley, Urso, Whaley, Blue, Williams, Guaspari & Selker, 1985; Nagai, 1988) and the ability of r-IL2 to generate activated cells effective in lysing tumor cell targets (Hayes, Moore, Pierz, Chen, Da Rosso, Nirenberg & Allen, 1993). We treated 3 patients (2 affected by disseminating cerebellar medulloblastoma, 1 by disseminating thalamic glioblastoma) by intrathecal r-IL2 via recervoir. In the first 2 patients, this treatment was preceded by alpha-IFN (also intrathecally). Monitoring of immunological effects of the treatment schedule involved kinetics of CSF and serum TNF-alpha, IL2s and IL2R during the first day of r-IL2 treatment, as well as on day +2 and +4 of both r-IL2 cycles, and assessment of CSF cells, protein and CSF and PB NK cell activity and CD3-CD56+ cells during the course of all treatment cycles. We also assessed clinical and neuroradiological effects of immunotherapy.
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Affiliation(s)
- A Salmaggi
- Istituto Nazionale Neurologico C. Besta, Milano, Italy
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31
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Hatam L, Schuval S, Bonagura VR. Flow cytometric analysis of natural killer cell function as a clinical assay. CYTOMETRY 1994; 16:59-68. [PMID: 8033735 DOI: 10.1002/cyto.990160109] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The 51Cr release assay has been the method of choice in analyzing natural killer cell (NK) function. Previous FCM cytotoxicity assays of NK activity have had numerous disadvantages that discouraged clinicians from attempting to evaluate NK function by flow cytometry. We demonstrate the effectiveness of using PKH-26, a stable membrane dye, to label the K562 target cells and propidium iodide intercalation into killed target cell DNA to determine the percentage of target cells killed by effector NK cells from the peripheral blood or bone marrow. This method compares favorably with the 51Cr release assay and is quicker and easier to perform. The percentage of cytotoxicity of NK cells (CD3- CD56+ and/or CD16+) from 10 normal subjects and 10 HIV-infected children are reported to demonstrate the feasibility of studying NK function in clinical populations by FCM. The potentiation of cytolysis by alpha-interferon and interleukin 2 in vitro was also compared between these two study groups. In addition, a patient whose leukemic blasts expressed CD56+ was also studied for NK activity using this flow cytometric assay. The benefits of using this flow cytometric approach to clinically assess NK function are discussed.
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Affiliation(s)
- L Hatam
- Department of Pediatrics, Schneider Children's Hospital, Long Island Jewish Medical Center, New Hyde Park, NY 11042
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32
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Blomberg K. Simultaneous measurement of natural killer cell cytotoxicity against each of three different target cell lines. J Immunol Methods 1994; 168:267-73. [PMID: 8308301 DOI: 10.1016/0022-1759(94)90064-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A time-resolved fluorometric assay for the simultaneous measurement of natural killer cell activity against three different lanthanide diethylenetriaminopentaacetate (LaDTPA) labelled target cell lines is described. The target cell line K-562 was labelled with SmDTPA, the cell line Molt with TbDTPA and the cell line Raji with EuDTPA. After co-incubation of the three target cell lines with effector cells the fluorescence of the lanthanides released from the lysed target cells was measured in an enhancer solution in which they formed highly fluorescent complexes. It was possible to differentiate the specific release from the three target cell lines because the emission lines of the europium, samarium and terbium complexes formed in the enhancer solution are well separated from each other. The autofluorescence from culture media supplemented with serum was avoided by the use of time-resolved fluorometry. The results show that applying fluorometry based on the combination of spectral and temporal resolution to natural killer cell assays, makes possible the simultaneous determination of lysis in up to three target cell lines in complex culture medium.
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Affiliation(s)
- K Blomberg
- Wallac Biochemical Laboratory, Turku, Finland
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33
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Affiliation(s)
- S Papa
- Istituto di Scienze Morfologiche, Universitá di Urbino, Italy
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34
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Chang L, Gusewitch GA, Chritton DB, Folz JC, Lebeck LK, Nehlsen-Cannarella SL. Rapid flow cytometric assay for the assessment of natural killer cell activity. J Immunol Methods 1993; 166:45-54. [PMID: 8228287 DOI: 10.1016/0022-1759(93)90327-4] [Citation(s) in RCA: 110] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A new assay using flow cytometry has been established to assess natural killer (NK) lytic activity with common bench top instrumentation. This assay uses a cyanine membrane dye to stain live K562 target cells and an iodide nuclear dye to evaluate dead cells, and provides a method of reliably separating target and effector cell populations. Effector cells remain unstained (fluorescent negative) throughout the procedure. The damaged pre-labeled targets appear doubly stained as their membranes become permeable to the nuclear stain during incubation. Percent cytotoxicity of various effector:target cell ratios is discerned using flow cytometric analysis after a 2 h incubation in this new assay, as compared to 4 h with the 51Cr-release 'gold standard' assay for cell-mediated cytotoxicity. Comparisons of normal individuals tested in parallel with the fluorescent dyes and the 51Cr-release assay have shown direct correlations. This new two-color flow cytometric technique has proven to be uncomplicated and reproducible when used in the clinical setting.
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Affiliation(s)
- L Chang
- Immunology Center, Loma Linda University Medical Center, CA 92354
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35
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Zamai L, Bareggi R, Santavenere E, Vitale M. Subtraction of autofluorescent dead cells from the lymphocyte flow cytometric binding assay. CYTOMETRY 1993; 14:951-4. [PMID: 8287738 DOI: 10.1002/cyto.990140815] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Flow cytometry allows the quantitative analysis of lymphocyte-target cell conjugates and the identification of the lymphocyte subset involved in the binding phenomenon. We recently described a methodology to identify the effector cells bound to K562 targets based on target cell autofluorescence coupled with lymphocyte staining by means of fluorescent monoclonal antibodies. Here we describe an implementation of the methodology that allows the subtraction of spontaneously dead targets to which lymphocytes may or may not adhere, thereby preventing the overestimation of the binding phenomenon and limiting its evaluation to living effector-target conjugates, thus preserving the specificity of the phenomenon.
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Affiliation(s)
- L Zamai
- Laboratorio Biologia Cellulare e Microscopia Elettronica, Istituto Ortopedico Rizzoli, Bologna, Italy
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36
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Radosević K, de Grooth BG, Greve J. Flow cytometric method for simultaneous detection of lymphocyte-K562 conjugates and immunophenotyping of the conjugate forming cells. CYTOMETRY 1993; 14:535-40. [PMID: 7689050 DOI: 10.1002/cyto.990140513] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A flow cytometric method for the simultaneous quantification and immunophenotyping of conjugates formed by human peripheral blood lymphocytes (PBL) and K562 cells has been developed. The method uses three fluorescent probes. One of the fluorescent probes (F-18) is used for labeling of PBL prior to incubation with K562 cells. After incubation the cells are treated with monoclonal antibodies labeled with phycoerythrin and Red613, respectively. The combination of F-18 fluorescence and light scattering signals enables identification and quantification of the conjugates while the fluorescence of the monoclonal antibodies provides information about the phenotype of the conjugate forming cells. Results obtained using different monoclonal antibodies are presented. The highest conjugate forming capacity has been found in the CD56+CD8+ population while the CD4+CD8- population has shown the lowest capacity to form conjugates. The influence of a washing step on the conjugate formation is discussed. The possibility to use the method in combination with a cytotoxicity assay is indicated.
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Affiliation(s)
- K Radosević
- University of Twente, Department of Applied Physics, Enschede, The Netherlands
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37
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Waniewski J, Palucka AK, Porwit A. Kinetic analysis of cytotoxic lymphocyte-target cell interaction as quantified by dual parameter flow cytometry. CYTOMETRY 1993; 14:393-400. [PMID: 8513695 DOI: 10.1002/cyto.990140408] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The kinetics of conjugate formation between leukemic cell lines (K562 and Daudi) and lymphokine-activated killer (LAK) cells was studied. A flow cytofluorometry method using double immunofluorescence staining was applied. During the first 15 min of incubation of LAK effectors with leukemic targets, a rapid binding occurred, followed by a plateau phase lasting until 30 min of observation. A considerable, yet not statistically significant, between-donor variability was noticed. A mathematical model of conjugate formation kinetics, based on the analogy to enzyme kinetics, was formulated and validated. Parameters of the model were related to the binding capacity of effector and target cells, and to the lifetime of conjugates and free cells. The concordance of theoretical curves with experimental data proved that the described model can be considered as a useful tool for the evaluation of kinetic and dynamic characterization of conjugate formation between leukemic targets and LAK effectors.
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Affiliation(s)
- J Waniewski
- Institute of Biocybernetics and Biomedical Engineering, Warsaw, Poland
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38
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Vitale M, Zamai L, Neri LM, Galanzi A, Facchini A, Rana R, Cataldi A, Papa S. The impairment of natural killer function in the healthy aged is due to a postbinding deficient mechanism. Cell Immunol 1992; 145:1-10. [PMID: 1423637 DOI: 10.1016/0008-8749(92)90307-b] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In order to study the fine mechanisms that underlie the impairment of non-MHC-restricted cytolytic activity which occurs during human aging, we examined by multiparametric flow cytometry the binding and lytic activities of human natural killer cells. The flow analysis revealed a striking increase of the CD16+8- subset, together with a significant decrease of CD8bright cells and total T cells (CD3+). Aging had no influence on the CD8dim subset. The total lytic activity expressed by PBL as well as their binding efficiency to K562 targets were moderately but not significantly increased in the elderly. In contrast, the cytotoxicity of the single target-bound natural killer cell (i.e., lytic efficiency) was deeply impaired in aged subjects, suggesting that the NK functional impairment observed in aging is located at postbinding level.
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Affiliation(s)
- M Vitale
- Istituto di Anatomia Umana Normale, Bologna, Italy
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39
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Provinciali M, Di Stefano G, Fabris N. Optimization of cytotoxic assay by target cell retention of the fluorescent dye carboxyfluorescein diacetate (CFDA) and comparison with conventional 51CR release assay. J Immunol Methods 1992; 155:19-24. [PMID: 1401964 DOI: 10.1016/0022-1759(92)90266-v] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
This paper describes the comparison between a fluorimetric NK assay based on the target cell retention of fluorescent dye carboxyfluorescein diacetate (cFDA) and standard 51Cr release assay. The results provide several suggestions to improve the cytotoxic assay based on the use of the fluorogenic substrate showing that the measurements of cFDA retained by target cells represent a method of evaluating cytotoxicity completely comparable to the 51Cr release assay.
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Affiliation(s)
- M Provinciali
- Gerontology Research Department, Italian National Research Centres on Aging (I.N.R.C.A.), Ancona
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40
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Richards SJ, Scott CS. Human NK cells in health and disease: clinical, functional, phenotypic and DNA genotypic characteristics. Leuk Lymphoma 1992; 7:377-99. [PMID: 1493440 DOI: 10.3109/10428199209049794] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Natural killer (NK) cells are the subject of great current interest because of their possible (in vivo) role in tumour cell surveillance and killing, and because of the potential application of cytokine-modulated NK cells in cancer immunotherapy. In addition, clonal proliferations of NK-associated (NKa) cell populations represent a high proportion of chronic (non-B) lymphoid malignancies and abnormal (both clonal and non-clonal) NKa components are being increasingly reported in association with diverse clinical pictures such as autoimmune disease. This communication extensively reviews what is presently known regarding normal and leukaemic NKa phenotypic diversity, the mechanisms of NK-mediated cytolysis, the role of NK cells in malignancy, and the diagnostic and cellular aspects of malignant NKa proliferations.
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Affiliation(s)
- S J Richards
- Yorkshire Leukaemia Diagnostic Unit, Department of Haematology, Cookridge Hospital, Leeds, England
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41
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Vitale M, Zamai L, Papa S, Mazzotti G, Facchini A, Monti G, Manzoli FA. Natural killer function in flow cytometry. III. Surface marker determination of K562-conjugated lymphocytes by dual laser flow cytometry. J Immunol Methods 1992; 149:189-96. [PMID: 1534339 DOI: 10.1016/0022-1759(92)90250-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The recognition of effector cell populations that are able to actively from conjugates with target cells is of major importance in studies of lymphocyte cytotoxicity. A number of methodologies have been described to identify the conjugates and count them, but there have been few studies of the binding capability of the different subsets of effector cells involved in the conjugation phenomenon. Here we describe a methodology that permits the study of two surface markers on lymphocytes conjugated to K562 target cells. In particular, the expression of low density CD8 (CD8dim) has been studied on both CD3+ and CD16+ lymphocytes bound to K562 target cells. Previously described methodologies, either optical microscopy or flow cytometry, were not able to identify the effector population by mAb double staining, especially in the case of antigens expressed at low density. The flow cytometric methodology described here permits the measurement of the binding activity of small lymphocyte subsets such as the CD3+ 8dim+ population. However, the method could be used to study the binding activity of any effector population defined by mAb double staining.
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Affiliation(s)
- M Vitale
- Istituto di Anatomia Umana Normale, Università di Bologna, Italy
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42
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Vitale M, Zamai L, Neri LM, Manzoli L, Facchini A, Papa S. Natural killer function in flow cytometry: identification of human lymphoid subsets able to bind to the NK sensitive target K562. CYTOMETRY 1991; 12:717-22. [PMID: 1838975 DOI: 10.1002/cyto.990120805] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
NK cells are a phenotypically, morphologically and functionally heterogeneous population. This has led to the current thought that the non-MHC restricted cytotoxicity is a cellular function that can be associated to different phenotypes. The recognition of the target cell and the conjugate formation is always the first step that eventually leads to the lysis of target. Characterization of the phenotypical pattern of the cells able to bind to K562 targets is the purpose of this study. A multi-parametric flow cytometry binding assay has been employed to identify the different K562-bound lymphocyte subsets. In particular, cells that coexpress the CD16 and CD8 antigens (CD16+8dim+) showed a significantly higher binding capacity than their CD16+8- counterpart. Moreover, the highest binding values have been found in cells that did not express the CD16 antigen at all, but still expressed the CD8dim antigen, such as the small CD8dim+3+ population. These data show that, the NK lytic function being dependent on binding, minor subpopulations must be considered among effector cells, which might correspond to different lytic activities. None of the previously published methodologies that analyze conjugates by flow cytometry or fluorescence microscopy were able to measure the binding capacity of small, double stained, lymphocyte subsets.
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Affiliation(s)
- M Vitale
- Istituto di Anatomia Umana Normale, Università di Bologna, Italy
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43
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Radosević K, Garritsen HS, Van Graft M, De Grooth BG, Greve J. A simple and sensitive flow cytometric assay for the determination of the cytotoxic activity of human natural killer cells. J Immunol Methods 1990; 135:81-9. [PMID: 2273268 DOI: 10.1016/0022-1759(90)90259-x] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A new, simple and sensitive flow cytometric assay for the determination of the cytotoxic activity of human natural killer cells is described. The assay is based on the use of two fluorochromes. The target cell population is stained with one fluorochrome (octadecylamine-fluorescein isothiocyanate, F-18) prior to incubation with the effector cells. F-18 remains in the membrane of the target cells even when they are killed thereby permitting a clear separation between effector and target cells. Dead cells are determined by staining with a second fluorochrome (propidium iodide) after incubation of effector and target cells. staining with a second fluorochrome (propidium iodide) after incubation of effector and target cells. F-18 is not toxic and does not decrease the cytotoxic activity of human natural killer cells. It is also stable (exchange between labeled and non-labeled cells is negligible in a period of at least 4 h at 37 degrees C) and it remains in the membrane of the killed cells. A clear distinction between unlabeled effector and labeled target cells is obtained, even after incubation of target and effector cells for 4 h at 37 degrees C and using a high effector cell-target cell ratio (75:1). A good correlation with the 51Cr release assay was obtained. A potential application of the flow cytometric cytotoxicity assay using whole blood instead of isolated lymphocytes is presented.
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Affiliation(s)
- K Radosević
- Department of Applied Physics, Twente University of Technology, Enschede, The Netherlands
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44
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Lydyard PM. Flow cytometry developments, uses of monoclonal antibodies and cell purification. Curr Opin Immunol 1989; 2:923-6. [PMID: 2562086 DOI: 10.1016/0952-7915(89)90179-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- P M Lydyard
- Department of Immunology, University College, Middlesex School of Medicine, London, UK
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