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Al-Kahiry W, Tawfik HS, Sharshira H, Ghanem A, El-Gammal M, Mikhael IL. Smudge cell percentage as a surrogate marker for ZAP-70 expression in patients with chronic lymphocytic leukemia. Blood Res 2018; 53:218-222. [PMID: 30310788 PMCID: PMC6170303 DOI: 10.5045/br.2018.53.3.218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 03/08/2018] [Accepted: 05/10/2018] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND This study aimed to evaluate the prognostic value of smudge cell percentage as a surrogate marker for zeta-chain-associated protein kinase 70 (ZAP-70) expression in chronic lymphocytic leukemia (CLL) patients. METHODS Sixty three newly diagnosed CLL patients were investigated at the Hematology Department of the Medical Research Institute of Alexandria University with complete blood count, lactate dehydrogenase, β2 microglobulin levels, ZAP-70 expression, and estimation of the percentage of smudge cells. RESULTS The percentage of smudge cells ranged from 2 to 58% with a mean of 24.03±13.98%. Higher percentages of smudge cells (>30%) were statistically significantly associated with markers of better prognosis (negative ZAP-70, early-stage disease according to the Binet and Rai staging systems, as well as low and intermediate risk CLL prognostic index). The percentage of smudge cells showed significantly negative correlation with the ZAP-70 expression and higher area under the curve for prediction of ZAP-70 positivity with better survival for 36 months in patients with >30% smudge cells. CONCLUSION The percentage of smudge cells at presentation of newly diagnosed CLL patients could be used as a surrogate marker for ZAP-70 expression and an additional prognostic marker for disease progression.
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Affiliation(s)
- Waiel Al-Kahiry
- Department of Hematology, Faculty of Medicine and Health Sciences, University of Aden, Aden, Yemen
| | - Hadeel Said Tawfik
- Department of Medical Laboratory Technology, Pharos University in Alexandria, Alexandria, Egypt
| | - Homam Sharshira
- Department of Hematology, Medical Research Institute, University of Alexandria, Alexandria, Egypt
| | - Amal Ghanem
- Department of Hematology, Medical Research Institute, University of Alexandria, Alexandria, Egypt
| | - Maha El-Gammal
- Department of Hematology, Medical Research Institute, University of Alexandria, Alexandria, Egypt
| | - Irene Lewis Mikhael
- Department of Hematology, Medical Research Institute, University of Alexandria, Alexandria, Egypt
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2
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Sciuto MR, Warnken U, Schnölzer M, Valvo C, Brunetto L, Boe A, Biffoni M, Krammer PH, De Maria R, Haas TL. Two-Step Coimmunoprecipitation (TIP) Enables Efficient and Highly Selective Isolation of Native Protein Complexes. Mol Cell Proteomics 2017; 17:993-1009. [PMID: 29217617 DOI: 10.1074/mcp.o116.065920] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 11/22/2017] [Indexed: 11/06/2022] Open
Abstract
Coimmunoprecipitation (co-IP) is one of the most frequently used techniques to study protein-protein (PPIs) or protein-nucleic acid interactions (PNIs). However, the presence of coprecipitated contaminants is a well-recognized issue associated with single-step co-IPs. To overcome this limitation, we developed the two-step co-IP (TIP) strategy that enables sequential coimmunoprecipitations of endogenous protein complexes. TIP can be performed with a broad range of mono- and polyclonal antibodies targeting a single protein or different components of a given complex. TIP results in a highly selective enrichment of protein complexes and thus outperforms single-step co-IPs for downstream applications such as mass spectrometry for the identification of PPIs and quantitative PCR for the analysis of PNIs. We benchmarked TIP for the identification of CD95/FAS-interacting proteins in primary human CD4+ T cells, which recapitulated all major known interactors, but also enabled the proteomics discovery of PPM1G and IPO7 as new interaction partners. For its feasibility and high performance, we propose TIP as an advanced tool for the isolation of highly purified protein-protein and protein-nucleic acid complexes under native expression conditions.
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Affiliation(s)
- Maria Rita Sciuto
- From the ‡Department of Hematology and Oncology, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy;
| | - Uwe Warnken
- §Functional Proteome Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 580, 69120, Heidelberg, Germany
| | - Martina Schnölzer
- §Functional Proteome Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 580, 69120, Heidelberg, Germany
| | - Cecilia Valvo
- From the ‡Department of Hematology and Oncology, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy.,¶Institute of General Pathology, Catholic University and Gemelli Polyclinic, Largo F. Vito 1, 00168, Rome, Italy
| | - Lidia Brunetto
- From the ‡Department of Hematology and Oncology, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Alessandra Boe
- From the ‡Department of Hematology and Oncology, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Mauro Biffoni
- From the ‡Department of Hematology and Oncology, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Peter H Krammer
- ‖Department of Tumor Immunology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - Ruggero De Maria
- ¶Institute of General Pathology, Catholic University and Gemelli Polyclinic, Largo F. Vito 1, 00168, Rome, Italy
| | - Tobias L Haas
- From the ‡Department of Hematology and Oncology, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy; .,¶Institute of General Pathology, Catholic University and Gemelli Polyclinic, Largo F. Vito 1, 00168, Rome, Italy
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3
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Gooden CE, Jones P, Bates R, Shallenberger WM, Surti U, Swerdlow SH, Roth CG. CD49d shows superior performance characteristics for flow cytometric prognostic testing in chronic lymphocytic leukemia/small lymphocytic lymphoma. CYTOMETRY PART B-CLINICAL CYTOMETRY 2016; 94:129-135. [PMID: 27221715 DOI: 10.1002/cyto.b.21384] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 05/16/2016] [Accepted: 05/23/2016] [Indexed: 01/03/2023]
Abstract
BACKGROUND CD49d is emerging as a powerful adverse prognostic marker in chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). However, flow cytometric testing for CD49d has not yet been widely adopted in the United States, in part due to the lack of establishment of its performance characteristics in the clinical setting, especially in comparison with the more common CLL/SLL prognostic markers CD38 and ZAP-70. METHODS CD49d expression levels in 124 CLL/SLL cases were assessed among peripheral blood (PB), bone marrow (BM), and lymph node (LN) specimens and correlated with available CD38 and ZAP-70 expression and cytogenetic findings. For 10 PB/BM specimens, the stability of CD49d, CD38, and ZAP-70 expression was assessed at <24 hours, 48 hours, 72 hours, and 96 hours. RESULTS 39% (28 of 71) PB, 56% (18 of 32) BM, and 71% (15 of 21) LN involved by CLL/SLL were CD49d+, using a ≥30% threshold. The mean for the CD49d+ cases was 2.8 standard deviations (SD) above the cutoff for positivity, compared with 1.7 SD for CD38 and 1.1 SD for ZAP-70. CD49d demonstrated the lowest mean SD (0.91) and coefficient of variation (CV) (8.0%) compared with CD38 (SD = 2.1, CV = 10.4%) and ZAP-70 (SD = 9.8, CV = 40.5%) in stability studies over a 96-hours time period. CD49d+ CLL/SLL correlated with trisomy 12 (P = 0.025) and lack of isolated deletion (13q) (P = 0.005). CD38+ CLL/SLL correlated with deletion (11q) (P = 0.025). ZAP-70 did not correlate with any underlying cytogenetic abnormality. CONCLUSIONS CD49d is a robust adverse prognostic marker in CLL/SLL with superior performance characteristics. © 2016 International Clinical Cytometry Society.
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Affiliation(s)
- Casey E Gooden
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Patricia Jones
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Ruth Bates
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Wendy M Shallenberger
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Urvashi Surti
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Steven H Swerdlow
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Christine G Roth
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.,Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas
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4
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Wu YJ, Wang H, Liang JH, Miao Y, Liu L, Qiu HR, Qiao C, Wang R, Li JY. Using the geometric mean fluorescence intensity index method to measure ZAP-70 expression in patients with chronic lymphocytic leukemia. Onco Targets Ther 2016; 9:797-805. [PMID: 26937202 PMCID: PMC4762435 DOI: 10.2147/ott.s94613] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Expression of ζ-chain-associated protein kinase 70 kDa (ZAP-70) in chronic lymphocytic leukemia (CLL) is associated with more aggressive disease and can help differentiate CLL from cases expressing mutated or unmutated immunoglobulin heavy chain variable region (IgHV) genes. However, standardizing ZAP-70 expression by flow cytometric analysis has proved unsatisfactory. The key point is that ZAP-70 is weakly expressed with a continuous expression pattern rather than a clear discrimination between positive and negative CLL cells, which means that the resulting judgment is subjective. Thus, in this study, we aimed at assessing the reliability and repeatability of ZAP-70 expression using the geometric mean fluorescence intensity (geo MFI) index method based on flow cytometry with 256-channel resolution in a series of 402 CLL patients and to compare ZAP-70 with other biological and clinical prognosticators. According to IgHV mutational status, we were able to confirm that the optimal cut-off point for the geo MFI index was 3.5 in the test set. In multivariate analyses that included the major clinical and biological prognostic markers for CLL, the prognostic impact of ZAP-70 expression appeared to have stronger discriminatory power when the geo MFI index method was applied. In addition, we found that ZAP-70-positive patients according to the geo MFI index method had shorter time to first treatment or overall survival (P=0.0002, P=0.0491). This is the first report showing that ZAP-70 expression can be evaluated by a new approach, the geo MFI index, which could be a useful prognostic method as it is more reliable, less subjective, and therefore better associated with improvement of CLL prognostication and prediction of clinical course.
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Affiliation(s)
- Yu-Jie Wu
- Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing, People's Republic of China
| | - Hui Wang
- Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing, People's Republic of China
| | - Jian-Hua Liang
- Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing, People's Republic of China
| | - Yi Miao
- Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing, People's Republic of China
| | - Lu Liu
- Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing, People's Republic of China
| | - Hai-Rong Qiu
- Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing, People's Republic of China
| | - Chun Qiao
- Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing, People's Republic of China
| | - Rong Wang
- Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing, People's Republic of China
| | - Jian-Yong Li
- Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing, People's Republic of China
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Craig F. Issue highlights--Cytometry Part B March 2014. CYTOMETRY PART B-CLINICAL CYTOMETRY 2015; 86:75-6. [PMID: 24591167 DOI: 10.1002/cyto.b.21161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Fiona Craig
- Division of Hematopathology, Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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6
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Vroblova V, Smolej L, Krejsek J. Pitfalls and limitations of ZAP-70 detection in chronic lymphocytic leukemia. ACTA ACUST UNITED AC 2012; 17:268-74. [PMID: 22971532 DOI: 10.1179/1607845412y.0000000015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Zeta-associated protein of 70 kDa (ZAP-70) is a tyrosine kinase that plays a role in signal transduction from the T-cell receptor. ZAP-70 is expressed in normal T-cells and NK-cells. Increased expression of ZAP-70 has been identified in chronic lymphocytic leukemia (CLL). CLL patients with increased ZAP-70 expression have significantly worse prognosis in terms of both progression-free survival and overall survival. There are several methods to quantify ZAP-70: polymerase chain reaction (PCR), immunoblotting, immunohistochemistry, and flow cytometry. Use of flow cytometry for ZAP-70 detection seems to be advantageous as this technique enables us to assess the presence of ZAP-70 separately on CLL clone, T-cells, and NK-cells. On the other hand, detection of ZAP-70 by flow cytometry is substantially influenced by many variables. The principal drawback of flow cytometry is the absence of consensus regarding selection of optimal anti-ZAP-70 antibody, fluorochrome conjugate, the most reliable staining technique, and optimal positivity threshold. This article summarizes pitfalls of flow cytometric analysis of ZAP-70 in CLL.
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Affiliation(s)
- V Vroblova
- Faculty of Medicine and University Hospital, Charles University, Hradec Kralove, Czech Republic.
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7
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Zhu P, Degheidy HA, Marti GE, Li S, Abbasi F, Wiestner A, Amstutz P, Tang CM. Quantitative detection of zeta-chain-associated protein 70 expression in chronic lymphocytic leukemia. Leuk Lymphoma 2012; 54:579-86. [PMID: 22839722 DOI: 10.3109/10428194.2012.715349] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Overexpression of zeta-chain-associated protein 70 (ZAP-70) was recently recognized as an independent prognostic marker for the aggressive form of chronic lymphocytic leukemia (CLL). The objective of this study was to demonstrate the feasibility and implementation of quantitative detection of ZAP-70 protein in B cells to clearly distinguish patients with CLL with the aggressive form of the disease. B cells were isolated from patient blood and lysed. Released ZAP-70 protein was detected using an immunomagnetic fluorescence assay. The assay protocol was developed using Jurkat cells and recombinant ZAP-70 (rZAP-70). The limit of detection was determined to be lower than 125 Jurkat cells and 39 pg of rZAP-70 protein. The signal response was linear over a wide dynamic range, from 125 to 40 000 Jurkat cells per test (R(2) = 0.9987) and from 0 to 40 000 pg rZAP-70 protein per test (R(2) = 0.9928). The results from 20 patients with CLL correlated strongly with flow cytometry analysis. Concordance between the two methods for positive and negative results was 100% (7/7) and 92% (12/13), respectively, while the overall concordance between the two methods was 95%. The assay reported here is a simple, reliable and reproducible method for quantitative detection of ZAP-70 in patient leukemic cells, without the need for cell fixation or permeabilization. The ZAP-70 signal was linear over a wide dynamic range, which we believe enables quantitative assessment of small changes in ZAP-70 expression over the course of the disease and in response to therapeutic intervention.
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Affiliation(s)
- Peixuan Zhu
- Creatv MicroTech, Inc., Potomac, MD 20854, USA.
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Preobrazhensky SN, Szankasi P, Bahler DW. Improved flow cytometric detection of ZAP-70 in chronic lymphocytic leukemia using experimentally optimized isotypic control antibodies. CYTOMETRY PART B-CLINICAL CYTOMETRY 2011; 82:78-84. [PMID: 22031469 DOI: 10.1002/cyto.b.20628] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Revised: 09/01/2011] [Accepted: 09/20/2011] [Indexed: 11/12/2022]
Abstract
INTRODUCTION Expression of ZAP-70 by chronic lymphocytic leukemia (CLL) is associated with more aggressive disease and can help differentiate CLL using mutated immunoglobulin heavy chain variable genes (VH) from cases expressing unmutated VH genes. However, flow cytometric detection of ZAP-70 in CLL shows considerable variability and may be of questionable significance because most laboratories cannot correlate their results to clinical outcome or VH mutational data. METHODS Seventy cases of CLL were evaluated for ZAP-70 using a previously optimized staining procedure and two different methods to eliminate nonspecific background staining. One method, not previously reported, used isotypic control antibodies, where the concentrations were adjusted/optimized so that normal B-cells stained negatively for ZAP-70. The other used ZAP-70 stained peripheral blood B-cells from normal donors. The percentages of ZAP-70 stained CLL cells above the two thresholds were compared. RESULTS Concentrations of isotypic control antibodies had to be increased from manufacture's recommendations to insure normal B-cells were ZAP-70 negative. ZAP-70 levels among the CLL cases formed a bimodal distribution using the optimized isotypic control threshold, with 30 having low values (0-32% positive) and 40 high values (60-99% positive). In contrast, a continuous distribution was obtained with the ZAP-70 stained B-cell threshold. VH mutational status strongly correlated with the optimized control values as 29/30 low ZAP-70 cases had mutated VH genes and 37/40 high ZAP-70 cases used unmutated VH genes. CONCLUSIONS Use of an optimized isotypic control threshold could increase the reliability of flow based ZAP-70 detection and correlates well with VH mutational status.
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Affiliation(s)
- Sergey N Preobrazhensky
- ARUP (Associated Regional and University Pathologists) Institute of Clinical and Experimental Pathology, University of Utah, Salt Lake City, Utah, USA
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9
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Degheidy HA, Venzon DJ, Farooqui MZ, Abbasi F, Arthur DC, Wilson WH, Wiestner A, Stetler-Stevenson MA, Marti GE. Methodological comparison of two anti-ZAP-70 antibodies. CYTOMETRY. PART B, CLINICAL CYTOMETRY 2011; 80:300-8. [PMID: 21472849 PMCID: PMC3461319 DOI: 10.1002/cyto.b.20591] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Revised: 12/17/2010] [Accepted: 01/24/2011] [Indexed: 11/07/2022]
Abstract
BACKGROUND ZAP-70 expression is a stage independent prognostic marker in CLL. However, interlaboratory variation is large, and there is neither a consensus nor a regulatory approved methodology. METHODS Two anti-ZAP70 clones (1E7.2 and SBZAP) were compared in 45 untreated CLL patients. Nine different methods for ZAP-70 expression analysis were evaluated: M1, isotype control to determine negative; M2, internal residual T-cell to determine positive; M3, normal donor (ND) T-cell to determine positive; M4, internal T-cell/clone ratio; M5, ND residual T-cell/clone ratio; M6, clone/normal remaining B-cell ratio; M7, clone/ND B- cell ratio; M8, CLL-Z score; M9, modified CLL-Z score. A scoring system was designed integrating both 1E7.2 and SBZAP clones to assign ZAP-70 expression. RESULTS The correlation coefficients for the four selected highest statistically significant methods were as follows (M1 = 0.71, M3 = 0.72, M7 = 0.67, and M9 = 0.64). These four methods were used to generate a combined score. The two reagents showed agreement using the designed scoring system for 37/45 samples (82%), and 8/45 (18%) showed equivocal result with one of the two clones. Seven of the eight equivocal samples were resolved using the scoring system. CONCLUSIONS Four of the nine methods of analysis were compared for each reagent. The use of two independent ZAP-70 reagents increases analytical certitude and the scoring method aids in the resolution of equivocal results. The combined use of two reagents, four methods of analysis, and a scoring method allowed for assignment of ZAP-70 expression in 44/45 samples (98%) tested and improved performance of this important prognostic assay.
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MESH Headings
- Aged
- Aged, 80 and over
- Antibodies, Monoclonal/blood
- Antibody Specificity
- Antigens, Surface/blood
- Antigens, Surface/immunology
- Female
- Flow Cytometry/methods
- Gene Expression/immunology
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/blood
- Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis
- Leukemia, Lymphocytic, Chronic, B-Cell/immunology
- Male
- Middle Aged
- ZAP-70 Protein-Tyrosine Kinase/blood
- ZAP-70 Protein-Tyrosine Kinase/immunology
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Affiliation(s)
- Heba A. Degheidy
- Center for Biologics Evaluation and Research, FDA, Bethesda, MD, USA
| | | | | | - Fatima Abbasi
- Center for Biologics Evaluation and Research, FDA, Bethesda, MD, USA
| | | | | | | | | | - Gerald E. Marti
- Center for Biologics Evaluation and Research, FDA, Bethesda, MD, USA
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Kaplan D, Meyerson HJ, Li X, Drasny C, Liu F, Costaldi M, Barr P, Lazarus HM. Correlation between ZAP-70, phospho-ZAP-70, and phospho-Syk expression in leukemic cells from patients with CLL. CYTOMETRY PART B-CLINICAL CYTOMETRY 2010; 78:115-22. [PMID: 20014315 DOI: 10.1002/cyto.b.20506] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
For patients with chronic lymphocytic leukemia (CLL), expression of ZAP-70 in the leukemic cells is an indicator of poor prognosis. However, the mechanism that accounts for this effect is not known. ZAP-70 expression has previously been associated with increased B cell antigen receptor signaling upon surface immunoglobulin ligation in vitro as shown by ZAP-70 and Syk phosphorylation. This finding has led to the suggestion that a more aggressive clinical course is correlated with B cell antigen receptor signaling. Using high resolution immunophenotyping to analyze CLL cells ex vivo (without stimulation in vitro), we have demonstrated CLL cells from all patients express some ZAP-70 and that increased expression of ZAP-70 is correlated with decreased levels of phosphorylated ZAP-70 and phosphorylated Syk measured directly ex vivo. Conversely, high levels of phosphorylated ZAP-70 and phosphorylated Syk are found only in samples with low levels of ZAP-70 expression, and Syk and ZAP-70 phosphorylation appear to be mostly independent of each other. Additionally, Syk phosphorylation is directly correlated with levels of p21(cip1), a cell cycle inhibitor and a p53 target. Together these findings suggest that lower levels of p21(cip1) and/or a defect in p53 activity may account in part for the more aggressive disease course in patients with high levels of ZAP-70 rather than enhanced B cell antigen receptor signaling as has been previously hypothesized.
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Affiliation(s)
- David Kaplan
- Department of Pathology, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio 44106, USA.
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Preobrazhensky SN, Bahler DW. Immunomagnetic bead separation of mononuclear cells from contaminating granulocytes in cryopreserved blood samples. Cryobiology 2009; 59:366-8. [PMID: 19766618 DOI: 10.1016/j.cryobiol.2009.09.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2009] [Revised: 09/04/2009] [Accepted: 09/15/2009] [Indexed: 11/30/2022]
Abstract
Density gradient centrifugation usually allows efficient separation of mononuclear cells from granulocytes using fresh human blood samples. However, we have found that with cryopreserved blood samples, density gradient centrifugation fails to separate granulocytes from mononuclear cells and have explored using immunomagnetic anti-CD15 microbeads as an alternate method to separate these cell populations. Using cryopreserved blood samples from 10 healthy donors we have shown that granulocytes express a significantly higher level of CD15 antigen than monocytes and lymphocytes, which allows for their efficient separation from mononuclear cells using anti-CD15 microbeads. This procedure is critical for purification of individual cell populations from cryopreserved leukocyte samples and could also potentially be applied to avoid granulocyte contamination of mononuclear cells isolated from stored blood and from patients with sepsis or thermal injury.
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Affiliation(s)
- Sergey N Preobrazhensky
- ARUP Laboratories, Institute for Clinical and Experimental Pathology, 500 Chipeta Way, Salt Lake City, UT 84108-1221, USA.
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