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David Navarro - One of the best experts on this subject based on the ideXlab platform.
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performance of the quantiferon cytomegalovirus cmv assay for detection and estimation of the magnitude and functionality of the cmv specific gamma interferon producing cd8 t Cell response in allogeneic Stem Cell Transplant recipients
Clinical and Vaccine Immunology, 2012Co-Authors: María Ángeles Clari, Isabel Benet, Elisa Costa, María José Remigia, Paula Amat, Dayana Bravo, Beatriz Munozcobo, Carlos Solano, David NavarroAbstract:The performance of the QuantiFERON-cytomegalovirus (CMV) assay was compared to that of a flow cytometry intraCellular cytokine staining (ICS) method for the detection of CMV-specific gamma interferon (IFN-γ)-producing CD8+ T-Cell responses in allogeneic Stem Cell Transplant (allo-SCT) recipients and for estimations of their magnitude and functionality. A total of 90 whole-blood specimens from 23 allo-SCT recipients was analyzed by both methods. Overall, the percentage of specimens that yielded concordant results by both methods was 68.8% (κ = 0.691; 95% confidence interval [CI], 0.548 to 0.835), and the sensitivity of the QuantiFERON-CMV assay for the detection of positive IFN-γ T-Cell responses (>0.2 IU/ml), taking the ICS method as the reference, was 76.3%. The magnitude of IFN-γ-producing CD8+ T-Cell responses to CMV-specific peptides measured with the QuantiFERON-CMV assay correlated significantly (σ = 0.695; P = 0.001]) CMV-specific CD8+ T-Cell responses, as quantitated by ICS. In summary, the data indicated that the QuantiFERON-CMV assay is less sensitive than the ICS method for the detection of CMV-specific IFN-γ-producing CD8+ T-Cell responses in the allo-SCT setting. Nevertheless, it allowed the estimation of the total and polyfunctional CMV-specific IFN-γ-producing CD8+ T-Cell responses in specimens that tested positive by both methods.
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Performance of the QuantiFERON-cytomegalovirus (CMV) assay for detection and estimation of the magnitude and functionality of the CMV-specific gamma interferon-producing CD8 + T-Cell response in allogeneic Stem Cell Transplant recipients
Clinical and Vaccine Immunology, 2012Co-Authors: María Ángeles Clari, Beatriz Munoz-cobo, Isabel Benet, Elisa Costa, María José Remigia, Paula Amat, Dayana Bravo, David NavarroAbstract:The performance of the QuantiFERON-cytomegalovirus (CMV) assay was compared to that of a flow cytometry intraCellular cytokine staining (ICS) method for the detection of CMV-specific gamma interferon (IFN-γ)-producing CD8(+) T-Cell responses in allogeneic Stem Cell Transplant (allo-SCT) recipients and for estimations of their magnitude and functionality. A total of 90 whole-blood specimens from 23 allo-SCT recipients was analyzed by both methods. Overall, the percentage of specimens that yielded concordant results by both methods was 68.8% (κ = 0.691; 95% confidence interval [CI], 0.548 to 0.835), and the sensitivity of the QuantiFERON-CMV assay for the detection of positive IFN-γ T-Cell responses (>0.2 IU/ml), taking the ICS method as the reference, was 76.3%. The magnitude of IFN-γ-producing CD8(+) T-Cell responses to CMV-specific peptides measured with the QuantiFERON-CMV assay correlated significantly (σ = 0.695; P =
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comparative evaluation of three automated syStems for dna extraction in conjunction with three commercially available real time pcr assays for quantitation of plasma cytomegalovirus dnaemia in allogeneic Stem Cell Transplant recipients
Journal of Clinical Microbiology, 2011Co-Authors: Dayana Bravo, María Ángeles Clari, Elisa Costa, María José Remigia, Beatriz Munozcobo, Carlos Solano, David NavarroAbstract:Limited data are available on the performance of different automated extraction platforms and commercially available quantitative real-time PCR (QRT-PCR) methods for the quantitation of cytomegalovirus (CMV) DNA in plasma. We compared the performance characteristics of the Abbott mSample preparation syStem DNA kit on the m24 SP instrument (Abbott), the High Pure viral nucleic acid kit on the COBAS AmpliPrep syStem (Roche), and the EZ1 Virus 2.0 kit on the BioRobot EZ1 extraction platform (Qiagen) coupled with the Abbott CMV PCR kit, the LightCycler CMV Quant kit (Roche), and the Q-CMV complete kit (Nanogen), for both plasma specimens from allogeneic Stem Cell Transplant (Allo-SCT) recipients (n = 42) and the OptiQuant CMV DNA panel (AcroMetrix). The EZ1 syStem displayed the highest extraction efficiency over a wide range of CMV plasma DNA loads, followed by the m24 and the AmpliPrep methods. The Nanogen PCR assay yielded higher mean CMV plasma DNA values than the Abbott and the Roche PCR assays, regardless of the platform used for DNA extraction. Overall, the effects of the extraction method and the QRT-PCR used on CMV plasma DNA load measurements were less pronounced for specimens with high CMV DNA content (>10,000 copies/ml). The performance characteristics of the extraction methods and QRT-PCR assays evaluated herein for clinical samples were extensible at Cell-based standards from AcroMetrix. In conclusion, different automated syStems are not equally efficient for CMV DNA extraction from plasma specimens, and the plasma CMV DNA loads measured by commercially available QRT-PCRs can differ significantly. The above findings should be taken into consideration for the establishment of cutoff values for the initiation or cessation of preemptive antiviral therapies and for the interpretation of data from clinical studies in the Allo-SCT setting.
Michael Boeckh - One of the best experts on this subject based on the ideXlab platform.
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cytomegalovirus in hematopoietic Stem Cell Transplant recipients
Hematology-oncology Clinics of North America, 2011Co-Authors: Per Ljungman, Michael Boeckh, Morgan HakkiAbstract:This article examines the clinical manifestations of and risk factors for cytomegalovirus (CMV). Prevention of CMV infection and disease are also explored. Antiviral resistance and management of CMV are examined.
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immune monitoring with itag mhc tetramers for prediction of recurrent or persistent cytomegalovirus infection or disease in allogeneic hematopoietic Stem Cell Transplant recipients a prospective multicenter study
Blood, 2010Co-Authors: Jan W Gratama, Michael Boeckh, John A Zaia, Stephen J Forman, Ryotaro Nakamura, Jan J Cornelissen, Rik A Brooimans, Karl Gaal, Kurtis R Bray, Gail H GasiorAbstract:textabstractCytomegalovirus (CMV) infection is an important cause of morbidity and mortality in hematopoietic Stem Cell Transplant recipients despite the introduction of postTransplantation viral monitoring and preemptive antiviral therapy. We evaluated the use of HLA class I tetramers in monitoring CMV-specific T-Cell recovery to predict patients at risk for CMV-related complications. This prospective multicenter clinical trial obtained nearly 1400 tetramer/allele results in more than 800 biweekly blood samples from 83 patients monitored for 1 year after Transplantation. Major HLA types were included (A*0101, A*0201, B*0702, B*0801, B*3501). iTAg MHC Tetramers (Beckman Coulter) were used to enumerate CMV-specific CD8+T Cells by flow cytometry using a single-platform absolute counting method. Assay variability was 8% or less and results were available within 3 hours. Delayed recovery of CMV-specific T Cells (<7 Cells/μL in all blood samples during the first 65 days after Transplantation) was found to be a significant risk factor for CMV-related complications; these patients were more likely to develop recurrent or persistent CMV infection (relative risk 2.6, CI 1.2-5.8, P=.01) than patients showing rapid recovery, which was associated with protection from CMV-related complications (P = .004). CMV tetramer-based immune monitoring, in conjunction with virologic monitoring, can be an important new tool to assess risk of CMV-related complications and to guide preemptive therapeutic choices.
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brief communication fatal human metapneumovirus infection in Stem Cell Transplant recipients
Annals of Internal Medicine, 2006Co-Authors: Janet A Englund, Robert C Hackman, Rhoda Morrow, David N Fredricks, Jane Kuypers, Michael Boeckh, Garrett W Nichols, Lawrence CoreyAbstract:Background: Human metapneumovirus (hMPV), a recently discovered respiratory virus, is associated with clinical disease in young and elderly persons. Objective: To determine the importance of hMPV in hematopoietic Stem-Cell Transplant recipients. Design: Retrospective survey of patients with consecutive residual bronchoalveolar lavage (BAL) samples. Setting: Referral cancer center. Patients: Hematopoietic Stem-Cell Transplant recipients who underwent BAL because of lower respiratory tract disease. Measurements: Bronchoalveolar lavage specimens were assayed by quantitative real-time polymerase chain reaction methods. Results: Human metapneumovirus was detected in BAL specimens from 5 of 163 patients (3.0%). Persistent viral infection was noted in 3 patients with several samples, and hMPV was detected in 1 of 2 lung specimens tested. Infected patients became symptomatic within the first 40 days after Transplantation. Initial symptoms included fever, cough, nasal congestion, and sore throat. Clinical findings included respiratory failure, pulmonary hemorrhage, and culture-negative septic shock. Four of 5 patients died with acute respiratory failure. Limitations: This retrospective study did not evaluate asymptomatic patients or those with mild disease. Conclusion: Human metapneumovirus infection in the lower respiratory tract is associated with respiratory failure in immunocompromised adults who were previously considered to have "idiopathic pneumonia." The infection may result in fulminant respiratory decompensation and shock after Transplantation.
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cytomegalovirus in hematopoietic Stem Cell Transplant recipients current status known challenges and future strategies
Biology of Blood and Marrow Transplantation, 2003Co-Authors: Michael Boeckh, Garrett W Nichols, John R. Wingard, Genovefa A Papanicolaou, Robert H Rubin, John A ZaiaAbstract:Abstract Cytomegalovirus (CMV) infection is a major cause of morbidity and mortality after hematopoietic Stem Cell Transplantation. Significant progress has been made in the prevention of CMV disease over the past decade, but prevention of late CMV disease continues to be a challenge in selected high-risk populations. The preTransplantation CMV serostatus of the donor and/or recipient remains an important risk factor for postTransplantation outcome despite the use of antiviral prophylaxis and preemptive therapy; CMV-seropositive recipients of T Cell-depleted grafts in particular continue to have a survival disadvantage compared with seronegative recipients with seronegative donors. The risk of developing antiviral drug resistance remains low in most patients; however, in a setting of intense immunosuppression (eg, after Transplantation from a haploidentical donor), the incidence may be as high as 8%. Primary CMV infection via blood transfusion can be reduced by the provision of seronegative or leukocyte-depleted blood products; however, a small risk of 1% to 2% of CMV disease remains. Surveillance and preemptive therapy are effective in preventing the sequelae of transfusion-related CMV infection. Indirect immunomodulatory effects of CMV are increasingly recognized in hematopoietic Stem Cell Transplant recipients. Strategies currently being investigated include long-term suppression of CMV with valganciclovir for the prevention of late CMV infection and disease, adoptive transfer of CMV-specific T Cells, and donor and recipient vaccination strategies.
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invasive aspergillosis in allogeneic Stem Cell Transplant recipients changes in epidemiology and risk factors
Blood, 2002Co-Authors: Kieren A Marr, Michael Boeckh, Rachel A Carter, Paul Martin, Lawrence CoreyAbstract:The incidence of postengraftment invasive aspergillosis (IA) in hematopoietic Stem Cell Transplant (HSCT) recipients increased during the 1990s. We determined risks for IA and outcomes among 1682 patients who received HSCTs between January 1993 and December 1998. Risk factors included host variables (age, underlying disease), Transplant variables (Stem Cell source), and late complications (acute and chronic graft-versus-host disease [GVHD], receipt of corticosteroids, secondary neutropenia, cytomegalovirus [CMV] disease, and respiratory virus infection). We identified risk factors associated with IA early after Transplantation (≤ 40 days) and after engraftment (41-180 days). Older patient age was associated with an increased risk during both periods. Chronic myelogenous leukemia (CML) in chronic phase was associated with low risk for early IA compared with other hematologic malignancies, aplastic anemia, and myelodysplastic syndrome. Multiple myeloma was associated with an increased risk for postengraftment IA. Use of human leukocyte antigen (HLA)–matched related (MR) peripheral blood Stem Cells conferred protection against early IA compared with use of MR bone marrow, but use of cord blood increased the risk of IA early after Transplantation. Factors that increased risks for IA after engraftment included receipt of T Cell–depleted or CD34-selected Stem Cell products, receipt of corticosteroids, neutropenia, lymphopenia, GVHD, CMV disease, and respiratory virus infections. Very late IA (> 6 months after Transplantation) was associated with chronic GVHD and CMV disease. These results emphasize the postengraftment timing of IA; risk factor analyses verify previously recognized risk factors (GVHD, receipt of corticosteroids, and neutropenia) and uncover the roles of lymphopenia and viral infections in increasing the incidence of postengraftment IA in the 1990s.
Kieren A Marr - One of the best experts on this subject based on the ideXlab platform.
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prospective surveillance for invasive fungal infections in hematopoietic Stem Cell Transplant recipients 2001 2006 overview of the Transplant associated infection surveillance network transnet database
Clinical Infectious Diseases, 2010Co-Authors: Dimitrios P Kontoyiennis, Kieren A Marr, Thomas J Walsh, Elias Anaissie, Benjamin J Park, Barbara D Alexander, David R Andes, John W Baddley, Janice M Brown, Lisa M BrumbleAbstract:Background. The incidence and epidemiology of invasive fungal infections (IFIs), a leading cause of death among hematopoeitic Stem Cell Transplant (HSCT) recipients, are derived mainly from single-institution retrospective studies. Methods. The Transplant Associated Infections Surveillance Network, a network of 23 US Transplant centers, prospectively enrolled HSCT recipients with proven and probable IFIs occurring between March 2001 and March 2006. We collected denominator data on all HSCTs preformed at each site and clinical, diagnostic, and outcome information for each IFI case. To estimate trends in IFI, we calculated the 12-month cumulative incidence among 9 sequential subcohorts. Results. We identified 983 IFIs among 875 HSCT recipients. The median age of the patients was 49 years; 60% were male. Invasive aspergillosis (43%), invasive candidiasis (28%), and zygomycosis (8%) were the most common IFIs. Fifty-nine percent and 61% of IFIs were recognized within 60 days of neutropenia and graft-versus-host disease, respectively. Median onset of candidiasis and aspergillosis after HSCT was 61 days and 99 days, respectively. Within a cohort of 16,200 HSCT recipients who received their first Transplants between March 2001 and September 2005 and were followed up through March 2006, we identified 718 IFIs in 639 persons. Twelve-month cumulative incidences, based on the first IFI, were 7.7 cases per 100 Transplants for matched unrelated allogeneic, 8.1 cases per 100 Transplants for mismatched-related allogeneic, 5.8 cases per 100 Transplants for matched-related allogeneic, and 1.2 cases per 100 Transplants for autologous HSCT. Conclusions. In this national prospective surveillance study of IFIs in HSCT recipients, the cumulative incidence was highest for aspergillosis, followed by candidiasis. Understanding the epidemiologic trends and burden of IFIs may lead to improved management strategies and study design.
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risks diagnosis and outcomes of invasive fungal infections in haematopoietic Stem Cell Transplant recipients
British Journal of Haematology, 2007Co-Authors: Penelope D Barnes, Kieren A MarrAbstract:Summary Invasive fungal infections (IFIs) continue to cause considerable morbidity and mortality in haematopoietic Stem Cell Transplant (HSCT) recipients. This review focuses on the risks for, and diagnosis of, IFIs (candidiasis, aspergillosis and other mould infections), and factors that affect current outcomes. Diagnosis of IFI is difficult, with the sensitivity of the gold standard tests (culture and histopathology) often <50%. Therefore, physicians rely on a constellation of clinical signs, radiography, culture, histopathology and adjunctive tests to establish diagnosis. HSCT recipients often have multiple co-morbidities, and understanding the current outcomes and prognostic variables is therefore important for overall management. This paper reviews historical trends and current data.
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breakthrough fungal infections in Stem Cell Transplant recipients receiving voriconazole
Clinical Infectious Diseases, 2004Co-Authors: Alexander Imhof, David N Fredricks, Janet A Englund, Kieren A Marr, Arunmozhi S BalajeeAbstract:Infection with voriconazole-resistant fungi may become problematic, because organisms with decreased susceptibility have been noted. Breakthrough fungal infections occurred in 13 of 139 patients who received voriconazole at our center during the period of September 1998 through September 2003. Zygomycetes were found in 6 patients, and Candida glabrata bloodstream infection occurred in 4 patients. Minimal inhibitory concentrations were ⩾1 µg/mL for all available isolates. Yeasts and molds with decreased susceptibility to voriconazole may cause invasive infection in patients treated successfully for aspergillosis.
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fusarium infection in hematopoietic Stem Cell Transplant recipients
Clinical Infectious Diseases, 2004Co-Authors: Marcio Nucci, Kieren A Marr, Flavio Queiroztelles, Carlos A Martins, Plinio Trabasso, Silvia Figueiredo Costa, Julio Cesar Voltarelli, Arnaldo Lopes Colombo, Alexander ImhofAbstract:To characterize the epidemiology and prognostic factors of invasive fusariosis in hematopoietic Stem Cell Transplant (HSCT) recipients, the records of HSCT recipients from 9 hospitals (7 in Brazil and 2 in the United States) were retrospectively reviewed. Sixty-one cases were identified: 54 in allogeneic HSCT recipients and 7 in autologous HSCT recipients. The incidence of fusariosis among allogeneic HSCT recipients varied between a range of 4.21-5.0 cases per 1000 in human leukocyte antigen (HLA)-matched related Transplant recipients to 20.19 cases per 1000 in HLA-mismatched Transplant recipients. The median time period between Transplantation and diagnosis of fusariosis was 48 days. Among allogeneic HSCT recipients, a trimodal distribution was observed: a first peak before engraftment, a second peak at a median of 62 days after Transplantation, and a third peak >1 year after Transplantation. The actuarial survival was 13% (median, 13 days). Persistent neutropenia was the single prognostic factor for death identified by multivariate analysis.
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invasive aspergillosis in allogeneic Stem Cell Transplant recipients changes in epidemiology and risk factors
Blood, 2002Co-Authors: Kieren A Marr, Michael Boeckh, Rachel A Carter, Paul Martin, Lawrence CoreyAbstract:The incidence of postengraftment invasive aspergillosis (IA) in hematopoietic Stem Cell Transplant (HSCT) recipients increased during the 1990s. We determined risks for IA and outcomes among 1682 patients who received HSCTs between January 1993 and December 1998. Risk factors included host variables (age, underlying disease), Transplant variables (Stem Cell source), and late complications (acute and chronic graft-versus-host disease [GVHD], receipt of corticosteroids, secondary neutropenia, cytomegalovirus [CMV] disease, and respiratory virus infection). We identified risk factors associated with IA early after Transplantation (≤ 40 days) and after engraftment (41-180 days). Older patient age was associated with an increased risk during both periods. Chronic myelogenous leukemia (CML) in chronic phase was associated with low risk for early IA compared with other hematologic malignancies, aplastic anemia, and myelodysplastic syndrome. Multiple myeloma was associated with an increased risk for postengraftment IA. Use of human leukocyte antigen (HLA)–matched related (MR) peripheral blood Stem Cells conferred protection against early IA compared with use of MR bone marrow, but use of cord blood increased the risk of IA early after Transplantation. Factors that increased risks for IA after engraftment included receipt of T Cell–depleted or CD34-selected Stem Cell products, receipt of corticosteroids, neutropenia, lymphopenia, GVHD, CMV disease, and respiratory virus infections. Very late IA (> 6 months after Transplantation) was associated with chronic GVHD and CMV disease. These results emphasize the postengraftment timing of IA; risk factor analyses verify previously recognized risk factors (GVHD, receipt of corticosteroids, and neutropenia) and uncover the roles of lymphopenia and viral infections in increasing the incidence of postengraftment IA in the 1990s.
María Ángeles Clari - One of the best experts on this subject based on the ideXlab platform.
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performance of the quantiferon cytomegalovirus cmv assay for detection and estimation of the magnitude and functionality of the cmv specific gamma interferon producing cd8 t Cell response in allogeneic Stem Cell Transplant recipients
Clinical and Vaccine Immunology, 2012Co-Authors: María Ángeles Clari, Isabel Benet, Elisa Costa, María José Remigia, Paula Amat, Dayana Bravo, Beatriz Munozcobo, Carlos Solano, David NavarroAbstract:The performance of the QuantiFERON-cytomegalovirus (CMV) assay was compared to that of a flow cytometry intraCellular cytokine staining (ICS) method for the detection of CMV-specific gamma interferon (IFN-γ)-producing CD8+ T-Cell responses in allogeneic Stem Cell Transplant (allo-SCT) recipients and for estimations of their magnitude and functionality. A total of 90 whole-blood specimens from 23 allo-SCT recipients was analyzed by both methods. Overall, the percentage of specimens that yielded concordant results by both methods was 68.8% (κ = 0.691; 95% confidence interval [CI], 0.548 to 0.835), and the sensitivity of the QuantiFERON-CMV assay for the detection of positive IFN-γ T-Cell responses (>0.2 IU/ml), taking the ICS method as the reference, was 76.3%. The magnitude of IFN-γ-producing CD8+ T-Cell responses to CMV-specific peptides measured with the QuantiFERON-CMV assay correlated significantly (σ = 0.695; P = 0.001]) CMV-specific CD8+ T-Cell responses, as quantitated by ICS. In summary, the data indicated that the QuantiFERON-CMV assay is less sensitive than the ICS method for the detection of CMV-specific IFN-γ-producing CD8+ T-Cell responses in the allo-SCT setting. Nevertheless, it allowed the estimation of the total and polyfunctional CMV-specific IFN-γ-producing CD8+ T-Cell responses in specimens that tested positive by both methods.
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Performance of the QuantiFERON-cytomegalovirus (CMV) assay for detection and estimation of the magnitude and functionality of the CMV-specific gamma interferon-producing CD8 + T-Cell response in allogeneic Stem Cell Transplant recipients
Clinical and Vaccine Immunology, 2012Co-Authors: María Ángeles Clari, Beatriz Munoz-cobo, Isabel Benet, Elisa Costa, María José Remigia, Paula Amat, Dayana Bravo, David NavarroAbstract:The performance of the QuantiFERON-cytomegalovirus (CMV) assay was compared to that of a flow cytometry intraCellular cytokine staining (ICS) method for the detection of CMV-specific gamma interferon (IFN-γ)-producing CD8(+) T-Cell responses in allogeneic Stem Cell Transplant (allo-SCT) recipients and for estimations of their magnitude and functionality. A total of 90 whole-blood specimens from 23 allo-SCT recipients was analyzed by both methods. Overall, the percentage of specimens that yielded concordant results by both methods was 68.8% (κ = 0.691; 95% confidence interval [CI], 0.548 to 0.835), and the sensitivity of the QuantiFERON-CMV assay for the detection of positive IFN-γ T-Cell responses (>0.2 IU/ml), taking the ICS method as the reference, was 76.3%. The magnitude of IFN-γ-producing CD8(+) T-Cell responses to CMV-specific peptides measured with the QuantiFERON-CMV assay correlated significantly (σ = 0.695; P =
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comparative evaluation of three automated syStems for dna extraction in conjunction with three commercially available real time pcr assays for quantitation of plasma cytomegalovirus dnaemia in allogeneic Stem Cell Transplant recipients
Journal of Clinical Microbiology, 2011Co-Authors: Dayana Bravo, María Ángeles Clari, Elisa Costa, María José Remigia, Beatriz Munozcobo, Carlos Solano, David NavarroAbstract:Limited data are available on the performance of different automated extraction platforms and commercially available quantitative real-time PCR (QRT-PCR) methods for the quantitation of cytomegalovirus (CMV) DNA in plasma. We compared the performance characteristics of the Abbott mSample preparation syStem DNA kit on the m24 SP instrument (Abbott), the High Pure viral nucleic acid kit on the COBAS AmpliPrep syStem (Roche), and the EZ1 Virus 2.0 kit on the BioRobot EZ1 extraction platform (Qiagen) coupled with the Abbott CMV PCR kit, the LightCycler CMV Quant kit (Roche), and the Q-CMV complete kit (Nanogen), for both plasma specimens from allogeneic Stem Cell Transplant (Allo-SCT) recipients (n = 42) and the OptiQuant CMV DNA panel (AcroMetrix). The EZ1 syStem displayed the highest extraction efficiency over a wide range of CMV plasma DNA loads, followed by the m24 and the AmpliPrep methods. The Nanogen PCR assay yielded higher mean CMV plasma DNA values than the Abbott and the Roche PCR assays, regardless of the platform used for DNA extraction. Overall, the effects of the extraction method and the QRT-PCR used on CMV plasma DNA load measurements were less pronounced for specimens with high CMV DNA content (>10,000 copies/ml). The performance characteristics of the extraction methods and QRT-PCR assays evaluated herein for clinical samples were extensible at Cell-based standards from AcroMetrix. In conclusion, different automated syStems are not equally efficient for CMV DNA extraction from plasma specimens, and the plasma CMV DNA loads measured by commercially available QRT-PCRs can differ significantly. The above findings should be taken into consideration for the establishment of cutoff values for the initiation or cessation of preemptive antiviral therapies and for the interpretation of data from clinical studies in the Allo-SCT setting.
Dayana Bravo - One of the best experts on this subject based on the ideXlab platform.
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performance of the quantiferon cytomegalovirus cmv assay for detection and estimation of the magnitude and functionality of the cmv specific gamma interferon producing cd8 t Cell response in allogeneic Stem Cell Transplant recipients
Clinical and Vaccine Immunology, 2012Co-Authors: María Ángeles Clari, Isabel Benet, Elisa Costa, María José Remigia, Paula Amat, Dayana Bravo, Beatriz Munozcobo, Carlos Solano, David NavarroAbstract:The performance of the QuantiFERON-cytomegalovirus (CMV) assay was compared to that of a flow cytometry intraCellular cytokine staining (ICS) method for the detection of CMV-specific gamma interferon (IFN-γ)-producing CD8+ T-Cell responses in allogeneic Stem Cell Transplant (allo-SCT) recipients and for estimations of their magnitude and functionality. A total of 90 whole-blood specimens from 23 allo-SCT recipients was analyzed by both methods. Overall, the percentage of specimens that yielded concordant results by both methods was 68.8% (κ = 0.691; 95% confidence interval [CI], 0.548 to 0.835), and the sensitivity of the QuantiFERON-CMV assay for the detection of positive IFN-γ T-Cell responses (>0.2 IU/ml), taking the ICS method as the reference, was 76.3%. The magnitude of IFN-γ-producing CD8+ T-Cell responses to CMV-specific peptides measured with the QuantiFERON-CMV assay correlated significantly (σ = 0.695; P = 0.001]) CMV-specific CD8+ T-Cell responses, as quantitated by ICS. In summary, the data indicated that the QuantiFERON-CMV assay is less sensitive than the ICS method for the detection of CMV-specific IFN-γ-producing CD8+ T-Cell responses in the allo-SCT setting. Nevertheless, it allowed the estimation of the total and polyfunctional CMV-specific IFN-γ-producing CD8+ T-Cell responses in specimens that tested positive by both methods.
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Performance of the QuantiFERON-cytomegalovirus (CMV) assay for detection and estimation of the magnitude and functionality of the CMV-specific gamma interferon-producing CD8 + T-Cell response in allogeneic Stem Cell Transplant recipients
Clinical and Vaccine Immunology, 2012Co-Authors: María Ángeles Clari, Beatriz Munoz-cobo, Isabel Benet, Elisa Costa, María José Remigia, Paula Amat, Dayana Bravo, David NavarroAbstract:The performance of the QuantiFERON-cytomegalovirus (CMV) assay was compared to that of a flow cytometry intraCellular cytokine staining (ICS) method for the detection of CMV-specific gamma interferon (IFN-γ)-producing CD8(+) T-Cell responses in allogeneic Stem Cell Transplant (allo-SCT) recipients and for estimations of their magnitude and functionality. A total of 90 whole-blood specimens from 23 allo-SCT recipients was analyzed by both methods. Overall, the percentage of specimens that yielded concordant results by both methods was 68.8% (κ = 0.691; 95% confidence interval [CI], 0.548 to 0.835), and the sensitivity of the QuantiFERON-CMV assay for the detection of positive IFN-γ T-Cell responses (>0.2 IU/ml), taking the ICS method as the reference, was 76.3%. The magnitude of IFN-γ-producing CD8(+) T-Cell responses to CMV-specific peptides measured with the QuantiFERON-CMV assay correlated significantly (σ = 0.695; P =
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comparative evaluation of three automated syStems for dna extraction in conjunction with three commercially available real time pcr assays for quantitation of plasma cytomegalovirus dnaemia in allogeneic Stem Cell Transplant recipients
Journal of Clinical Microbiology, 2011Co-Authors: Dayana Bravo, María Ángeles Clari, Elisa Costa, María José Remigia, Beatriz Munozcobo, Carlos Solano, David NavarroAbstract:Limited data are available on the performance of different automated extraction platforms and commercially available quantitative real-time PCR (QRT-PCR) methods for the quantitation of cytomegalovirus (CMV) DNA in plasma. We compared the performance characteristics of the Abbott mSample preparation syStem DNA kit on the m24 SP instrument (Abbott), the High Pure viral nucleic acid kit on the COBAS AmpliPrep syStem (Roche), and the EZ1 Virus 2.0 kit on the BioRobot EZ1 extraction platform (Qiagen) coupled with the Abbott CMV PCR kit, the LightCycler CMV Quant kit (Roche), and the Q-CMV complete kit (Nanogen), for both plasma specimens from allogeneic Stem Cell Transplant (Allo-SCT) recipients (n = 42) and the OptiQuant CMV DNA panel (AcroMetrix). The EZ1 syStem displayed the highest extraction efficiency over a wide range of CMV plasma DNA loads, followed by the m24 and the AmpliPrep methods. The Nanogen PCR assay yielded higher mean CMV plasma DNA values than the Abbott and the Roche PCR assays, regardless of the platform used for DNA extraction. Overall, the effects of the extraction method and the QRT-PCR used on CMV plasma DNA load measurements were less pronounced for specimens with high CMV DNA content (>10,000 copies/ml). The performance characteristics of the extraction methods and QRT-PCR assays evaluated herein for clinical samples were extensible at Cell-based standards from AcroMetrix. In conclusion, different automated syStems are not equally efficient for CMV DNA extraction from plasma specimens, and the plasma CMV DNA loads measured by commercially available QRT-PCRs can differ significantly. The above findings should be taken into consideration for the establishment of cutoff values for the initiation or cessation of preemptive antiviral therapies and for the interpretation of data from clinical studies in the Allo-SCT setting.