title: Quantitative expression of HLA class I molecules in acute non-lymphoblastic leukaemia cells.
abstract: The present study concerns a panel of 33 acute non lymphoblastic leukaemia (ANLL) patients, previously typed for HLA-A,B serological specificities and including samples with a normal HLA-A,B phenotype (3,4 detected specificities) as well as samples with missing and extra specificities. Samples were analysed at the protein and/or RNA level in order to verify whether the observed typing anomalies were due to a modified quantitative expression of class I molecules. The number of HLA-A,B assigned specificities correlated significantly with the cell surface class I expression detected by indirect immunofluorescence using the monomorphic anti-class I MoAb W6/32 (Spearman rank correlation test, P < 0.01) and with the amount of class I Heavy Chain (HC, P < 0.05) and beta-2-microglobulin (beta 2m, P < 0.05) evaluated by Western blot in whole cell extracts. The RNA analysis suggested a HC-beta 2m coordinated down regulation at the mRNA level in a patient with no assigned HLA-A,B specificities. Another patient with no detectable HLA-A,B specificities showed a low expression selectively of the beta 2m protein. The results reported here demonstrate a heterogenous quantitative HLA class I expression in ANLL blasts, analogous to results reported for solid tumours.
authors.affiliation: Dipartimento di Genetica, Biologia e Chimica Medica, Università di Torino, Italy.
authors.forename: S
authors.initials: S
authors.lastname: D'Alfonso
authors.forename: P
authors.initials: P
authors.lastname: Savoia
authors.forename: G
authors.initials: G
authors.lastname: Pitti
authors.forename: D
authors.initials: D
authors.lastname: Peruccio
authors.forename: C
authors.initials: C
authors.lastname: Pozzi
authors.forename: T
authors.initials: T
authors.lastname: Crepaldi
authors.forename: M
authors.initials: M
authors.lastname: Falda
authors.forename: F
authors.initials: F
authors.lastname: Ficara
authors.forename: L
authors.initials: L
authors.lastname: Resegotti
authors.forename: P
authors.initials: P
authors.lastname: Momigliano Richiardi
mesh_terms: D000951:Antigens, Neoplasm / Q000096:biosynthesis* / Q000235:genetics; D015973:Gene Expression Regulation, Leukemic; D015234:HLA-A Antigens / Q000096:biosynthesis* / Q000235:genetics; D015235:HLA-B Antigens / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000235:genetics / Q000276:immunology*; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics; D014411:Neoplastic Stem Cells / Q000276:immunology* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics; D001613:beta 2-Microglobulin / Q000096:biosynthesis / Q000235:genetics
chemical_list: D000951:Antigens, Neoplasm; D015234:HLA-A Antigens; D015235:HLA-B Antigens; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D001613:beta 2-Microglobulin