Depletion of circulating IgM memory B cells predicts unfavourable outcome in COVID-19.

Impaired immune responses have been hypothesised to be a possible trigger of unfavourable outcomes in coronavirus disease 2019 (COVID-19). We aimed to characterise IgM memory B cells in patients with COVID-19 admitted to an internal medicine ward in Northern Italy. Overall, 66 COVID-19 patients (mean age 74 ± 16.

Features, reason for testing, and changes with time of 583 paroxysmal nocturnal hemoglobinuria clones from 529 patients: a multicenter Italian study.

In this study, we aimed at disclosing the main features of paroxysmal nocturnal hemoglobinuria (PNH) clones, their association with presentation syndromes, and their changes during follow-up. A large-scale, cooperative collection (583 clones from 529 patients) of flow cytometric and clinical data was entered into a national repository. Reason for testing guidelines were provided to the 41 participating laboratories, which followed the 2010 technical recommendations for PNH testing by Borowitz.

A dynamic prognostic model to predict survival in post-polycythemia vera myelofibrosis.

Post-polycythemia vera myelofibrosis (post-PV MF) is a late evolution of PV. In 647 patients with PV, we found that leukocytosis leukocyte count>(15x10(9)/L) at diagnosis is a risk factor for the evolution of post-PV MF. In a series of 68 patients who developed post-PV MF, median survival was 5.

Familial chronic myeloproliferative disorders: clinical phenotype and evidence of disease anticipation.

Purpose: Chronic myeloproliferative disorders (CMDs) have sporadic occurrence. However, familial clustering is reported. The purpose of this study was to assess the prevalence and the clinical phenotype of familial CMDs, and to study the anticipation of disease onset in successive generations.

Relation between JAK2 (V617F) mutation status, granulocyte activation, and constitutive mobilization of CD34+ cells into peripheral blood in myeloproliferative disorders.

We studied the relationship between granulocyte JAK2 (V617F) mutation status, circulating CD34(+) cells, and granulocyte activation in myeloproliferative disorders. Quantitative allele-specific polymerase chain reaction (PCR) showed significant differences between various disorders with respect to either the proportion of positive patients (53%-100%) or that of mutant alleles, which overall ranged from 1% to 100%. In polycythemia vera, JAK2 (V617F) was detected in 23 of 25 subjects at diagnosis and in 16 of 16 patients whose disease had evolved into myelofibrosis; median percentages of mutant alleles in these subgroups were significantly different (32% versus 95%, P < .

Combination of rituximab, cyclophosphamide, and vincristine induces complete hematologic remission of splenic marginal zone lymphoma.

Optimal treatment for splenic marginal zone lymphoma (MZL) is not clearly established. Splenectomy has been proposed as the treatment of choice in patients with cytopenias and/or symptoms caused by an enlarged spleen. Splenic MZL, which expresses the CD20 antigen on tumor cell surfaces, is a disease entity candidate to treatment with anti-CD20 monoclonal antibodies.

Dendritic cell recovery after allogeneic stem-cell transplantation in acute leukemia: correlations with clinical and transplant characteristics.

We have analyzed the kinetics of reconstitution of circulating dendritic cell (DC) subsets (myeloid-DC1 and lymphoid-DC2) in 19 patients affected by acute leukemia undergoing allogeneic hematopoietic stem-cell transplantation (HSCT). We have found that pretransplant DC1 and DC2 were lower in leukemic patients than in healthy subjects (P = 0.003 and P = 0.

Clinical utility of the absolute number of circulating CD34-positive cells in patients with chronic myeloproliferative disorders.

Background And Objectives: Flow cytometry enumeration of peripheral blood CD34-positive cells provides reliable measurements of circulating hematopoietic progenitors in humans. Since the absolute number of circulating CD34-positive cells has been previously found to be elevated in myelofibrosis with myeloid metaplasia (MMM), we prospectively studied the clinical utility of this parameter in the work-up of patients with chronic myeloproliferative disorders.

Design And Methods: Of the 248 consecutive patients enrolled in this study, 106 had polycythemia vera (PV), 90 essential thrombocythemia (ET), and 52 myelofibrosis with myeloid metaplasia (MMM).

Multidimensional flow cytometry immunophenotyping of hematologic malignancy.

Immunophenotyping of hematologic malignancies represents one of the most relevant clinical applications of flow cytometry. Classically, leukemic/lymphomatous cells have been considered to reflect the immunophenotypic characteristics of different precursors and mature healthy cells blocked at certain differentiation stages. Recently, accumulating evidence has shown that neoplastic cells display several aberrant phenotypic patterns.