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Flow cytometry analysis of neutrophil myeloperoxidase expression in peripheral blood samples will be performed within 24 h of MDS diagnostic evaluation and blinded to the reference standard. Peripheral blood samples will be collected in 5 ml (EDTA) anticoagulant plastic tubes and processed within 24 h maximum of collection. The samples will be stored at 4°C overnight.

Blood samples containing at least 105 neutrophils will be incubated with a panel of antibodies conjugated to fluorochromes, according to the manufacturers' recommendations.

At least 10,000 cell events will be acquired on a 3-laser, 8-color flow cytometer and analyzed using Becton Dickinson (BD) Fluorescence-activated cell sorting (FACS) Diva Software version 6. Each marker will be expressed as median, geometric and arithmetic mean, regular and robust coefficient of variation.

Flow cytometry analysis of neutrophil myeloperoxidase expression

Tatiana Raskovalova, MD

Richard Veyrat-Masson, MD

Sophie Park, MD

Marc Berger, MD

Jean-Yves Cesbron, MD

Marie-Christine Jacob, MD

Myelodysplastic syndromes (MDS) constitute a heterogeneous group of clonal bone marrow neoplasms that predominate in the elderly, with a median age at diagnosis of 70 years. MDS are characterized by peripheral blood cytopenia and morphologic dysplasia for one or more hematopoietic cell lineage, reflecting ineffective hematopoiesis.

The diagnostic work-up of MDS includes a bone marrow aspirate and biopsy, which is an invasive procedure, for cytomorphologic and cytogenetic evaluations. Because the prevalence of disease is lower than 20% in subjects referred for suspected MDS, many patients are exposed to unnecessary bone marrow aspiration-related discomfort and harms.

An objective assay is highly desirable for accurately ruling out MDS based on peripheral blood samples, which may obviate the need for invasive bone marrow aspiration and biopsy in patients with negative results.

Few studies have investigated the value of peripheral blood flow cytometric analysis for the diagnosis of MDS and/or chronic myelomonocytic leukemia (CMML). Although promising, these studies lacked replication of their results, used a case-control design, which was prone to spectrum bias, or yielded imprecise diagnostic accuracy estimates due to relatively limited sample sizes.

Anecdotal evidence supports the potential of flow cytometric analysis of peripheral blood neutrophil myeloperoxidase expression for the diagnosis of MDS and CMML. Myeloperoxidase is an enzyme synthetized during myeloid differentiation that constitutes the major component of neutrophil azurophilic granules. Myeloperoxidase expression may reflect neutrophil hypogranulation, which is a classical although subjective dysplastic feature of MDS. Flow cytometric analysis of myeloperoxidase expression in bone marrow neutrophil granulocytes has been used for discriminating low versus high grade MDS. Yet a study reporting on the accuracy of flow cytometric analysis of peripheral blood neutrophil myeloperoxidase expression for the diagnosis of MDS is still lacking, to our knowledge.

In this study, the investigators hypothesize that flow cytometric analysis of neutrophil myeloperoxidase expression in peripheral blood may accurately rule out MDS and obviate the need for bone marrow aspiration and biopsy, with sensitivity approaching 100%, in routine practice.

In this observational diagnostic accuracy study, burden will be null for recruited patients. No specific intervention is assigned to participants. All diagnostic testing, procedures, and medication ordering are performed at the discretion of attending physicians. Flow cytometry analysis of peripheral blood neutrophil myeloperoxidase expression will not require additional blood sample. A test result will have no impact on patient management. No follow-up visits are planned in this cross-sectional study.

The primary objective of MPO-MDS-pilot study is to estimate the accuracy of flow cytometric analysis of neutrophil myeloperoxidase expression in peripheral blood for the diagnosis of myelodysplastic syndromes (MDS) and/or chronic myelomonocytic leukemia (CMML).

The secondary objectives are:

1. to provide accuracy estimates for prespecified thresholds of neutrophil myeloperoxidase expression in peripheral blood in ruling out MDS and/or CMML.
2. to estimate the prevalence of alternate diagnosis established by bone marrow cytomorphology.

The MPO-MDS-pilot project is a multicenter, phase II, cross-sectional, diagnostic accuracy study of consecutive unselected patients referred for suspected MDS or CMML.

Screening: All consecutive patients referred to the immuno-hematology lab at the study sites for suspicion of MDS will be screened for eligibility. A lab physician will review inclusion and exclusion criteria, using computerized medical and laboratory records.

Recruitment: Participants will be included in the study once all the screening activities have been conducted and only if the patient meets all inclusion and none exclusion criteria. The consent for flow cytometry analysis of peripheral blood sample and data collection through chart review will be sought under a regime of "non-opposition" (opt-out): after appropriate written information is delivered, cross-sectional data will be collected except in case of opposition from the patient. All patients included in the study will be assigned a unique patient identification number. This number will be used to identify the patient throughout the study.

Index test: Flow cytometry analysis of neutrophil myeloperoxidase expression in peripheral blood will be performed within 24 h of MDS diagnostic evaluation and blinded to the reference standard.

Reference standard: The diagnosis of MDS will be established according to the World Health Organization (WHO) classification, based on clinical data, peripheral blood cytopenia, cytomorphology of peripheral blood and bone marrow aspirate, and cytogenetic analysis. The criteria for MDS diagnosis are 1) the presence of ≥10% dysplastic cells in any hematopoietic lineage, 2) the exclusion of acute myeloid leukemia (defined by the presence of ≥20% peripheral blood or bone marrow blasts), and 3) the exclusion of reactive etiologies of dysplasia. Cytopenia is defined by hemoglobin concentration \<10 g/dL, platelet count \<100x109/L, and/or absolute neutrophil count \<1.8 x109/L. Yet a diagnosis of MDS could be made with milder levels of cytopenia. Idiopathic cytopenia of uncertain significance (ICUS) is defined by unexplained mild persistent cytopenia for at least 6 months and the failure to establish the diagnosis to MDS according to published guidelines. Consistent with WHO classification, MDS subcategorization will rely on the degree of dysplasia (unilineage versus multilineage), blast percentages, presence of ring sideroblasts, and cytogenetic analysis (del(5q)). The criteria for CMML diagnosis are 1) the presence of persistent peripheral blood monocytosis ≥1 x109/L, and 2) monocyte accounting for more than 10% of the white blood cell differential count. Evaluation of bone marrow cytomorphology will be performed prospectively by experienced hematopathologists who are blinded to the index test results.

Patients with confirmed suspicion of MDS: Participants for whom the diagnosis of MDS (or CMML) is confirmed by the reference standard will be categorized as patients with confirmed suspicion of MDS.

Patients with unconfirmed suspicion of MDS: Participants for whom the diagnosis of MDS (or CMML) is ruled out by the reference standard will be categorized as patients with unconfirmed suspicion of MDS. This latter subgroup will include patients with ICUS, as defined in accordance with published guidelines

Follow-up: No follow-up visit is planned in this cross-sectional diagnostic accuracy study.

Flow Cytometric Analysis of Peripheral Blood Neutrophil Myeloperoxidase Expression and Myelodysplastic Syndromes

Flow Cytometric Analysis of Peripheral Blood Neutrophil Myeloperoxidase Expression for Ruling Out Myelodysplastic Syndromes: A Pilot Diagnostic Accuracy Study

The principal investigators will respond directly to data requests by providing a de-identified data set. Individual participant data that underlie the results reported in the published articles (i.e., main text, tables, figures, and appendices) will be supplied.

The primary outcome is the discrimination of the index test (i.e., flow cytometry analysis of neutrophil myeloperoxidase expression in peripheral blood) for the diagnosis of myelodysplastic syndromes (MDS) or chronic myelomonocytic leukemia (CMLL) quantified by the area under the ROC curve point estimate along with its 95% confidence interval.

University Hospital, Grenoble

Performance of flow cytometric analysis of neutrophil myeloperoxidase expression in peripheral blood samples will be blinded to the reference standard. Peripheral blood samples will be collected in 5 ml (EDTA) anticoagulant plastic tubes and processed on the same day of collection.

Blood samples will be incubated with a panel of antibodies conjugated to fluorochromes, according to the manufacturers' recommendations.

At least 10,000 cell events will be acquired on a 3-laser, 8/12-color flow cytometer and analyzed using flow cytometry software. Myeloperoxidase expression in the peripheral blood neutrophil population within an individual subject will be expressed as intra-individual robust coefficient of variation (RCV).

Flow cytometric analysis of neutrophil myeloperoxidase expression

Tatiana RASKOVALOVA

Richard VEYRAT-MASSON

Delphine MANZONI

Anne-Catherine LHOUMEAU

Caroline BRET

Caroline MAYEUR-ROUSSE

Michel TICCHIONI

Chrystelle ABDO

Myelodysplastic syndromes (MDS) are clonal bone marrow neoplasms characterized by dysplasia and ineffective hematopoiesis leading to peripheral blood cytopenias, with an increased risk of progression to acute myeloid leukemia. The conventional diagnostic work-up of MDS relies on cytomorphological evaluation of bone marrow, which may be complemented by conventional cytogenetic, flow cytometry, and molecular analysis by next generation sequencing techniques.

Suspicion of MDS is the commonest reason for bone marrow aspirate in older patients with unexplained peripheral blood cytopenias. Yet many patients are exposed to unnecessary bone marrow aspiration-related discomfort and harms, because of the limited prevalence of disease among subjects referred for suspected MDS. In this context, a valid and reliable assay based on peripheral blood sample that accurately discriminates MDS from other cytopenia etiologies without requiring invasive bone marrow aspiration is warranted.

The accuracy of peripheral blood neutrophil myeloperoxidase expression quantified by flow cytometric analysis for the diagnosis of MDS is supported by three primary studies totaling 211 individuals. An intra-individual robust coefficient of variation (RCV) value for neutrophil myeloperoxidase expression lower than 30.0% accurately ruled out MDS, with both sensitivity and negative predictive value point estimates of 100%, in consecutive patients with suspected disease. This biomarker might obviate the need for cytomorphological evaluation of bone marrow aspirate for up to 35% of patients referred for suspected MDS. Although promising, these preliminary results require replication in an independent external validation sample.

The broad aim of the multicenter MPO-MDS-Valid study project is to prospectively validate the diagnostic accuracy of intra-individual RCV for peripheral blood neutrophil myeloperoxidase expression quantified by flow cytometric analysis among consecutive patients referred for suspected MDS.

The primary objective of the MPO-MDS-Valid study is to estimate the discriminative accuracy (i.e., area under the ROC curve point estimate along with 95% confidence interval \[CI\]) of the intra-individual RCV for neutrophil myeloperoxidase expression in peripheral blood for the diagnosis of MDS in consecutive patients.

The secondary objectives are:

1. To estimate the negative predictive value of the intra-individual RCV for neutrophil myeloperoxidase expression in peripheral blood (with a prespecified threshold of 30.0%) for ruling out MDS in consecutive patients.
2. To estimate the prevalence of alternate diagnoses established by bone marrow cytomorphology among true negative patients (i.e., patients with intra-individual RCV value lower than 30.0% and for whom MDS was ruled out by the reference method).

Study design: The MPO-MDS-Valid study project is a multicenter diagnostic accuracy study of an index test by comparison with a reference standard in unselected consecutive patients. An institutional review board (Comité de Protection des Personnes Nord Ouest III) reviewed and approved the study protocol and the information form, prior to study initiation. No specific intervention is assigned to participants. All diagnostic testing, procedures, and medication ordering are performed at the discretion of attending physicians. The index test result will have no impact on patient management.

Screening: All consecutive patients referred for suspicion of MDS to the immuno-hematology lab at the study sites will be screened for eligibility. A lab physician will review inclusion and exclusion criteria, using computerized medical and laboratory records.

Recruitment: Participants will be included in the study once all the screening activities have been conducted and only if the patient meets all inclusion and none exclusion criteria. The consent for flow cytometry analysis of peripheral blood sample and data collection through chart review will be sought under a regime of "non-opposition" (opt-out): after appropriate written information is delivered, data will be collected except in case of opposition from the patient. All patients included in the study will be assigned a unique patient identification number. This number will be used to identify the patient throughout the study.

Index test: Flow cytometric analysis of neutrophil myeloperoxidase expression in peripheral blood will be blinded to the reference standard. Myeloperoxidase expression in the peripheral blood neutrophil population within an individual subject will be expressed as RCV. The intra-individual RCV is calculated as the robust standard deviation divided by the median. The robust standard deviation is a function of the deviation of individual data points to the median of the study population. Intra-individual RCV is expressed as percentage and reflects the variability in myeloperoxidase expression in the peripheral blood neutrophil population within an individual subject.

Reference standard: At each study site, cytomorphological evaluation of bone marrow aspirate will be performed by experienced hematopathologists blinded to the index test.

Morphologic assessment may be complemented by bone marrow flow cytometric score, karyotype, and molecular profiling, where relevant. The reference criteria for MDS are 1) the presence of ≥10% dysplastic cells in any hematopoietic lineage on bone marrow aspirate, and 2) the exclusion of acute myeloid leukemia (defined by the presence of ≥20% bone marrow blasts). Consistent with WHO classification, MDS subcategorization will be based on the degree of dysplasia (unilineage versus multilineage), blast percentages, presence of ring sideroblasts, and cytogenetic analysis (del(5q)).

The reference criteria for chronic myelomonocytic leukemia (CMML) diagnosis are 1) the presence of persistent peripheral blood monocytosis ≥1 x109/L, and 2) monocyte accounting for more than 10% of the white blood cell differential count. Idiopathic cytopenia of uncertain significance (ICUS) will be defined by unexplained mild persistent cytopenia for 4 to 6 months and the failure to establish the diagnosis of MDS according to reference criteria.

Patients with confirmed suspicion of MDS: Participants for whom the diagnosis of MDS (or CMML) is confirmed by the reference standard will be categorized as patients with confirmed suspicion of MDS.

Patients with unconfirmed suspicion of MDS: Participants for whom the diagnosis of MDS (or CMML) is ruled out by the reference standard will be categorized as patients with unconfirmed suspicion of MDS. This latter subgroup will include patients with ICUS, as defined in accordance with published guidelines.

Flow Cytometric Analysis of Peripheral Blood Neutrophil Myeloperoxidase Expression for Ruling Out Myelodysplastic Syndromes: Protocol for a Diagnostic Accuracy Study

The principal investigator will respond directly to data requests by providing a de-identified data set. Individual participant data that underlie the results reported in the published articles (i.e., main text, tables, figures, and appendices) will be supplied.

The area under the ROC curve point estimate along with 95% confidence interval will quantify the accuracy of the index test (i.e., intra-individual RCV for neutrophil myeloperoxidase expression in peripheral blood) for the diagnosis of myelodysplastic syndromes (MDS) or chronic myelomonocytic leukemia (CMML). The reference diagnosis will be established by cytomorphological evaluation of bone marrow aspirate performed by independent experienced hematopathologists blinded to the index test results. Morphologic assessment may be complemented by bone marrow flow cytometric score, karyotype, and molecular profiling, where relevant.

The negative predictive value point estimate along with 95% confidence interval for the index test (i.e., intra-individual robust coefficient of variation with a prespecified threshold of 30.0%) will be computed by comparison with the reference standard for myelodysplastic syndromes (MDS) or chronic myelomonocytic leukemia (CMML)

Prevalence point estimate (along with 95% confidence interval) of alternate diagnosis established by bone marrow examination for unconfirmed suspicions of myelodysplastic syndromes with intra-individual RCV\< 30.0% for neutrophil myeloperoxidase expression in peripheral blood.

Flow cytometry analysis of neutrophil myeloperoxidase expression in peripheral blood samples will be performed within 24 h of MDS diagnostic evaluation and blinded to the reference standard. Peripheral blood samples will be collected in 5 ml (EDTA) anticoagulant plastic tubes and processed within 24 h maximum of collection.

Blood sample will be stained according to the manufacturers' recommendations with a lyophilized cocktail ("LyotubeTM ready-to-use", BD Bioscience).

At least 10,000 neutrophils will be acquired on a 3-laser, 8-color BD FACSCanto-II TM flow cytometer (BD Biosciences, San José, CA).

Each marker will be expressed as median, geometric and arithmetic mean, regular and robust coefficient of variation.

Diagnostic Test: Flow cytometry analysis of neutrophil myeloperoxidase expression

Carmen Aanei, MD

Myelodysplastic syndromes (MDS) comprise a heterogeneous group of clonal bone marrow neoplasms that predominate in the elderly, with a median age at diagnosis of 70 years. The diagnosis of MDS relies on peripheral blood cytopenia and morphologic dysplasia for one or more hematopoietic cell lineage. Cytopenia is evidenced with hemogram while dysplasia requires bone marrow aspirate, which is an invasive procedure .

Considering the low prevalence of disease among subjects referred for suspected MDS, many patients are exposed to unnecessary bone marrow aspiration-related discomfort and harms. Therefore, an objective assay based on a peripheral blood sample that accurately discriminates MDS from other cytopenia etiologies is highly desirable.

We have previously developed and refined a flow cytometric analysis protocol for quantifying neutrophil MPO expression in peripheral blood at three university-affiliated hospitals (i.e., Clermont-Ferrand, Saint-Etienne, and Grenoble) (Raskovalova et al, Hematologica 2019). We found that the robust coefficient of variation (RCV, computed as the robust standard deviation divided by the median) within an individual subject was the best parameter in discriminating patients with versus without MDS.

Although promising, flow cytometric analysis of neutrophil MPO expression in peripheral blood is technically complex, time consuming, and not standardized. Hence, its performance requires specific expertise and the results show substantial variability. A single ready-to-use tube with lyophilized antibodies would have the potential to standardize the measurement of neutrophil MPO expression in peripheral blood across laboratories, with results available within 30-60 min in routine practice.

In this study, the investigators hypothesize that a standardized and semi-automatic flow cytometric assay of neutrophil MPO expression in peripheral blood could accurately rule out MDS and obviate the need for bone marrow aspiration and biopsy, with sensitivity and negative predictive value estimates approaching 100%.

In this observational diagnostic accuracy study, burden will be null for recruited patients. No specific intervention is assigned to participants. All diagnostic testing, procedures, and medication ordering are performed at the discretion of attending physicians. A test result will have no impact on patient management. .Compliance with current guidelines disseminated by the French Haute Autorité de Santé (HAS) will be advocated for the diagnostic work-up of patients with suspected MDS. No follow-up visits are planned in this cross-sectional study.

The primary objective of MPO-MDS-develop study is to estimate the discriminative accuracy (i.e., area under the ROC curve along with 95% CI) of a standardized and semi-automatic flow cytometric assay of neutrophil MPO expression in peripheral blood for the diagnosis of MDS in adult patients.

The secondary objectives are to assess:

1. intra-laboratory reproducibility (intra- and inter-assay precision) for intra-individual RCV measurement of neutrophil MPO expression in peripheral blood;
2. specimen stability for intra-individual RCV measurement of neutrophil MPO expression in peripheral blood at different time points in comparison with H0 (stored at 4°C and at room temperature);
3. inter-laboratory reproducibility for intra-individual RCV measurement of neutrophil MPO expression in peripheral blood;
4. the negative predictive value for intra-individual RCV measurement of neutrophil MPO expression in peripheral blood (with a prespecified threshold of 30.0%) in ruling out MDS in consecutive adult patients.

The MPO-MDS-Develop project is a multicenter, cross-sectional, diagnostic accuracy study of an index test by comparison with a reference standard, in unselected consecutive patients.

Screening: All consecutive patients referred to the immuno-hematology lab at the study sites for suspicion of MDS will be screened for eligibility. A lab physician will review inclusion and exclusion criteria, using computerized medical and laboratory records.

Recruitment: Participants will be included in the study once all the screening activities have been conducted and only if the patient meets all inclusion and none exclusion criteria. The consent for flow cytometry analysis of peripheral blood sample and data collection through chart review will be sought under a regime of "non-opposition" (opt-out): after appropriate written information is delivered, cross-sectional data will be collected except in case of opposition from the patient. All patients included in the study will be assigned a unique patient identification number. This number will be used to identify the patient throughout the study.

Index test: Flow cytometry analysis of neutrophil myeloperoxidase expression in peripheral blood will be performed using a single ready-to-use tube with lyophilized antibodies developed in partnership with Becton Dickinson France SAS and blinded to the reference standard.

Reference standard: The diagnosis of MDS will be established according to the World Health Organization (WHO) classification, based on clinical data, peripheral blood cytopenia, cytomorphology of peripheral blood and bone marrow aspirate, and cytogenetic analysis. The criteria for MDS diagnosis are 1) the presence of ≥10% dysplastic cells in any hematopoietic lineage, 2) the exclusion of acute myeloid leukemia (defined by the presence of ≥20% peripheral blood or bone marrow blasts), and 3) the exclusion of reactive etiologies of dysplasia. Cytopenia is defined by hemoglobin concentration \<10 g/dL, platelet count \<100x109/L, and/or absolute neutrophil count \<1.8 x109/L. Yet a diagnosis of MDS could be made with milder levels of cytopenia. Idiopathic cytopenia of uncertain significance (ICUS) is defined by unexplained mild persistent cytopenia for at least 6 months and the failure to establish the diagnosis to MDS according to published guidelines. Consistent with WHO classification, MDS subcategorization will rely on the degree of dysplasia (unilineage versus multilineage), blast percentages, presence of ring sideroblasts, and cytogenetic analysis (del(5q)). The criteria for CMML diagnosis are 1) the presence of persistent peripheral blood monocytosis ≥1 x109/L, and 2) monocyte accounting for more than 10% of the white blood cell differential count. Evaluation of bone marrow cytomorphology will be performed prospectively by experienced hematopathologists who are blinded to the index test results.

Patients with confirmed suspicion of MDS: Participants for whom the diagnosis of MDS (or CMML) is confirmed by the reference standard will be categorized as patients with confirmed suspicion of MDS.

Patients with unconfirmed suspicion of MDS: Participants for whom the diagnosis of MDS (or CMML) is ruled out by the reference standard will be categorized as patients with unconfirmed suspicion of MDS. This latter subgroup will include patients with ICUS, as defined in accordance with published guidelines.

Follow-up: No follow-up visit is planned in this cross-sectional diagnostic accuracy study.

Development and Prospective Validation of a Standardized Flow Cytometric Assay of Peripheral Blood Neutrophil Myeloperoxidase Expression for Ruling Out Myelodysplastic Syndromes.

The primary outcome is the reference diagnosis of MDS or CMML established by bone marrow examination (with Perls staining) by two independent experienced hematopathologists blinded to the index test results. Disagreements will be solved by a third hematopathologist. Bone marrow aspirate will be repeated within 4 to 6 months for patients with idiopathic cytopenia of uncertain significance (ICUS) or non-conclusive bone marrow examination.

Anti-Infective Agents

Hydrogen Peroxide

Sivan Achituv, MD

Ronit Elhasid, MD

Identifying the post-transplantation phase wherein neutrophils recover their ability to release NETs could shed new light on the mechanism responsible for the increased susceptibility to infection among these patients and aid in improving their prophylactic antimicrobial treatment. Therefore, we aim to examine neutrophil extracellular traps (NETs) formation, in relation to other neutrophil functions like chemotaxis, superoxide production, hydrogen peroxide production, and the presence of myeloperoxidase, in pediatric patients undergoing autologous and allogeneic hematopoietic stem cell transplantation (HSCT).

Although neutrophil engraftment takes place 10 to 14 days after autologous HSCT, and 15 to 30 days after allogeneic HSCT, using an ablative conditioning regimen, neutrophil dysfunction may persist for longer periods. Relatively scant data exists on neutrophil function following HSCT. After autologous HSCT, the respiratory burst and phagocytosis may be decreased for up to 3 months. After allogeneic HSCT, respiratory burst and chemotaxis are generally decreased for 4 to 6 months. Factors such as continuation of chemotherapy, immunosuppression, and GVHD contribute to this prolonged dysfunction. No data exist on reconstitution of NETs following HSCT.

Nets production and other neutrophil functions will be examined at several time points: before transplantation, at neutrophil engraftment, 6 weeks, 3 months, 6 months, 9 months, 1 year, 1.5 years, 2 years, and 3 years post-transplant, or until normalization of neutrophil function at 2 consecutive time points. Data gathered on patients will cover:

1. Demographics.
2. Tumor histological type, staging, previous chemotherapy regimen, and initial response to treatment.
3. HSCT procedure - type of conditioning regimen, type of graft (autologous or allogeneic - related donor/unrelated donor/cord blood), use of bone marrow stem cells (SCs) or peripheral mobilized SCs, number of SCs given, post-transplant immunosuppression, post-transplant prophylactic antimicrobial treatment, infections during the study period, and GVHD occurrence and treatment.

Neutrophil examinations will be done in collaboration with the Laboratory for Leukocyte Function of the Department of Pediatrics, Meir Medical Center, Kfar Saba and NETs visualization with the Department of Cellular Microbiology at the Max Planck Institute for Infection Biology, Berlin.

10cc of peripheral venous blood will be collected from each patient at several time points: Before transplant, at neutrophil engraftment, 6 weeks, 3 months, 4 months, 6 months, 9 months, 1 year, 1.5 years, 2 years, and 3 years post-transplant, or until normalization of NETs formation in 2 consecutive examinations.

Neutrophil Extracellular Traps Formation Post-hematopoietic Stem Cell Transplantation

Neutrophil Extracellular Traps (NETs) Formation Post-hematopoietic Stem Cell Transplantation (HSCT) and Its Relation to Chemotaxis and Creation of Reactive Oxygen Species

Study title	NCT ID	Conditions	Interventions	Eligibility	Organization
Flow Cytometric Analysis of Peripheral Blood Neutrophil Myeloperoxidase Expression and Myelodysplastic Syndromes	NCT03363399	Myelodysplastic... Chronic Myelomo...	Flow cytometry ...	50 Years -	University Hospital, Grenoble
Flow Cytometric Analysis of Peripheral Blood Neutrophil Myeloperoxidase Expression for Ruling Out Myelodysplastic Syndromes: Protocol for a Diagnostic Accuracy Study	NCT05175469	Myelodysplastic...	Flow cytometric...	18 Years - 100 Years	University Hospital, Grenoble
Flow Cytometric Analysis of Peripheral Blood Neutrophil Myeloperoxidase Expression for Ruling Out Myelodysplastic Syndromes: Protocol for a Diagnostic Accuracy Study	NCT05175469	Myelodysplastic...	Flow cytometric...	18 Years - 100 Years	University Hospital, Grenoble
Development and Prospective Validation of a Standardized Flow Cytometric Assay of Peripheral Blood Neutrophil Myeloperoxidase Expression for Ruling Out Myelodysplastic Syndromes.	NCT04399018	Myelodysplastic...	Diagnostic Test...	18 Years - 100 Years	University Hospital, Grenoble
Neutrophil Extracellular Traps Formation Post-hematopoietic Stem Cell Transplantation	NCT01491230	Childhood Cance...		- 21 Years	Tel-Aviv Sourasky Medical Center
Flow Cytometric Analysis of Peripheral Blood Neutrophil Myeloperoxidase Expression and Myelodysplastic Syndromes	NCT03363399	Myelodysplastic... Chronic Myelomo...	Flow cytometry ...	50 Years -	University Hospital, Grenoble

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