title: Flow cytometric study of potential target antigens (CD19, CD20, CD22, CD33) for antibody-based immunotherapy in acute lymphoblastic leukemia: analysis of 552 cases.
abstract: Monoclonal antibody (MoAb)-based therapies have opened innovative treatment avenues that have impacted on the management of patients with both neoplastic and non-neoplastic hematological diseases. The aim of our study was to evaluate in a large series of cases of acute lymphoblastic leukemia (ALL) the expression of specific antigens, CD19, CD20, CD22, and CD33, for which MoAbs are available for clinical use. For each antigen, evaluation was based on the percentage of positive leukemic cells and the degree of antigen expression by mean fluorescence intensity (MFI) and antibody binding capacity (ABC) that were correlated with age, immunophenotype, and presence/absence of particular molecular markers. We can document that some of the analyzed antigens showed a degree of expression related to the B-cell maturation profile, and that the antigen expression intensity appeared to vary according to the presence of specific genetic markers. These findings suggest that the possible clinical use of a given MoAb in patients with ALL should take into account both the maturation profile of the leukemic cells and the presence of a given molecular transcript. Only clinical studies will conclusively demonstrate whether the differences in antigenic expression truly correlate with the different therapeutic efficacies of the various clinical grade MoAbs.
authors.affiliation: Department of Cellular Biotechnologies and Hematology, Division of Hematology, Sapienza University of Rome, Rome, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Raponi
authors.forename: Maria Stefania
authors.initials: MS
authors.lastname: De Propris
authors.forename: Stefania
authors.initials: S
authors.lastname: Intoppa
authors.forename: Maria Laura
authors.initials: ML
authors.lastname: Milani
authors.forename: Antonella
authors.initials: A
authors.lastname: Vitale
authors.forename: Loredana
authors.initials: L
authors.lastname: Elia
authors.forename: Omar
authors.initials: O
authors.lastname: Perbellini
authors.forename: Giovanni
authors.initials: G
authors.lastname: Pizzolo
authors.forename: Robin
authors.initials: R
authors.lastname: Foá
authors.forename: Anna
authors.initials: A
authors.lastname: Guarini
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000627:therapeutic use*; D015703:Antigens, CD / Q000276:immunology / Q000378:metabolism; D018941:Antigens, CD19 / Q000276:immunology / Q000378:metabolism; D018951:Antigens, CD20 / Q000276:immunology / Q000378:metabolism; D015214:Antigens, Differentiation, Myelomonocytic / Q000276:immunology / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D016130:Immunophenotyping; D008875:Middle Aged; D015514:Oncogene Proteins, Fusion / Q000235:genetics; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000378:metabolism / Q000473:pathology / Q000628:therapy; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism*; D054218:Precursor T-Cell Lymphoblastic Leukemia-Lymphoma / Q000378:metabolism / Q000473:pathology / Q000628:therapy; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051918:Sialic Acid Binding Ig-like Lectin 2 / Q000276:immunology / Q000378:metabolism; D063268:Sialic Acid Binding Ig-like Lectin 3; D014158:Transcription, Genetic; D055815:Young Adult
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D018941:Antigens, CD19; D018951:Antigens, CD20; D015214:Antigens, Differentiation, Myelomonocytic; C571163:CD33 protein, human; D015514:Oncogene Proteins, Fusion; D051918:Sialic Acid Binding Ig-like Lectin 2; D063268:Sialic Acid Binding Ig-like Lectin 3