CAL2 monoclonal antibody is a rapid and sensitive assay for the detection of calreticulin mutations in essential thrombocythemia patients.

Autor: Bonifacio M; Department of Medicine, Section of Hematology, University of Verona, P.le L.A.Scuro 10, Verona, 37134, Italy. massimiliano.bonifacio@univr.it., Montemezzi R; Department of Medicine, Section of Hematology, University of Verona, P.le L.A.Scuro 10, Verona, 37134, Italy., Parisi A; Department of Diagnostics and Public Health, Section of Pathological Anatomy, University of Verona, Verona, Italy., De Matteis G; Department of Diagnostics and Public Health, Section of Clinical Biochemistry, University of Verona, Verona, Italy., Bertorelle R; Immunology and Molecular Oncology, Veneto Institute of Oncology IOV-IRCCS, Padua, Italy., Scaffidi L; Department of Medicine, Section of Hematology, University of Verona, P.le L.A.Scuro 10, Verona, 37134, Italy., Candiotto C; Immunology and Molecular Oncology, Veneto Institute of Oncology IOV-IRCCS, Padua, Italy., Lippi G; Department of Diagnostics and Public Health, Section of Clinical Biochemistry, University of Verona, Verona, Italy., Zamò A; Department of Oncology, Section of Pathological Anatomy, University of Turin, Turin, Italy., Chilosi M; Department of Pathology, Pederzoli Hospital, Peschiera del Garda, Verona, Italy., Pizzolo G; Department of Medicine, Section of Hematology, University of Verona, P.le L.A.Scuro 10, Verona, 37134, Italy., Scarpa A; Department of Diagnostics and Public Health, Section of Pathological Anatomy, University of Verona, Verona, Italy., Krampera M; Department of Medicine, Section of Hematology, University of Verona, P.le L.A.Scuro 10, Verona, 37134, Italy.
Jazyk: angličtina
Zdroj: Annals of hematology [Ann Hematol] 2019 Oct; Vol. 98 (10), pp. 2339-2346. Date of Electronic Publication: 2019 Jun 27.
DOI: 10.1007/s00277-019-03741-8
Abstrakt: Calreticulin (CALR) mutations are detected in the majority of JAK2 wild type patients with essential thrombocythemia (ET). Unlike JAK2 V617F and MPL point mutations, CALR mutations are highly heterogeneous, with several types of indels being reported so far. CAL2 is a monoclonal antibody specifically recognizing the C-neoterminal peptide derived from all the frameshift mutations of CALR. We retrospectively analysed 172 ET patients diagnosed at our Institution from 1980 to 2015. In JAK2 V617F - and MPL W515K/L -wild type patients CALR mutations were searched on peripheral blood and CAL2 immunostaining was performed on bone marrow. In addition, bone marrow biopsies were histologically reviewed for megakaryocytic features. Thirty-one patients (18%) were CALR-mutated. Concordance between molecular and immunohistological detection of CALR mutations was near complete, albeit a single patient was found to be positive by molecular tests only. Two patterns were defined in CAL2-positive bone marrow samples, characterized by staining of almost only megakaryocytes (pattern A: 41%) or staining of megakaryocytes and ≥ 2% small non megakaryocytic elements (pattern B: 59%), at least partially being myeloid precursors. Pattern B biopsies had higher cellularity and number of megakaryocytes compared to pattern A samples. In this series, CAL2 allowed rapid and cost-efficient identification of CALR-mutated ET patients. The biological significance of different staining pattern should be confirmed in wider and independent series.
Databáze: MEDLINE
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