title: HLA-DM expression is elevated in ETV6-AML1 translocation-positive pediatric acute lymphoblastic leukemia.
abstract: MHC Class II antigen processing and presentation to CD4+ T cells is important in anti-tumor immunity. ETV6-AML1-positive precursor-B acute lymphoblastic leukemia (pre-B ALL) is associated with good outcome and late relapse. We analyzed HLA-DR and the MHC Class II processing components HLA-DO, HLA-DM, and Class II-associated invariant chain peptide (CLIP) expression, in ETV6-AML1-positive and ETV6-AML1-negative ALL. Overall, CLIP expression was low, while HLA-DM was significantly higher in ETV6-AML1-positive cells. No significant difference in HLA-DO was observed. The HLA-DR(high)/CLIP(low)/HLA-DM(high) phenotype strongly suggests that ETV6-AML1 leukemia will induce favorable immune responses and may in part explain the characteristic late relapses associated with ETV6-AML1 pre-B ALL.
authors.affiliation: University of British Columbia and British Columbia's Children's Hospital, Pediatric Hematology/Oncology/BMT, 4480 Oak Street, Room A119, Vancouver, BC, Canada V6H3V4.
authors.forename: Wasil A
authors.initials: WA
authors.lastname: Jastaniah
authors.forename: Angela J
authors.initials: AJ
authors.lastname: Alessandri
authors.forename: Gregor S D
authors.initials: GS
authors.lastname: Reid
authors.forename: Kirk R
authors.initials: KR
authors.lastname: Schultz
mesh_terms: D002648:Child; D050676:Core Binding Factor Alpha 2 Subunit / Q000235:genetics*; D006681:HLA-D Antigens / Q000276:immunology*; D006801:Humans; D016130:Immunophenotyping; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics* / Q000276:immunology*; D050783:Proto-Oncogene Proteins c-ets / Q000235:genetics*; D012097:Repressor Proteins / Q000235:genetics*; D014178:Translocation, Genetic; D000097764:ETS Translocation Variant 6 Protein
chemical_list: D050676:Core Binding Factor Alpha 2 Subunit; D006681:HLA-D Antigens; D050783:Proto-Oncogene Proteins c-ets; D012097:Repressor Proteins; D000097764:ETS Translocation Variant 6 Protein; C084245:HLA-DM antigens; C493728:RUNX1 protein, human