title: Regulation of the expression of MHC class I and II by class II transactivator (CIITA) in hematopoietic cells.
abstract: In order to develop an effective immunotherapy for hematological malignancies, we investigated the applicability of class II transactivator (CIITA), which had been demonstrated to regulate the expression of MHC class II (MHC-II) by assembling the transcription factors of MHC-II molecules, for immunotherapy by potentiating the antigenicity of tumour cells by inducing MHC expression. First, 32 hematopoietic cell lines were analysed for the expression of HLA-DR, CIITA, RFX5 or HLA-ABC. Fourteen cell lines were positive and 18 were negative for HLA-DR. All the 14 HLA-DR positive cell lines were demonstrated to express CIITA mRNA by RT-PCR. On the other hand, in all the 18 HLA-DR negative cell lines, the expression of CIITA was not demonstrated. RFX5, which is one of the transcription factors of MHC-II, was expressed ubiquitously in all 32 cell lines. Three cell lines out of 23 hematopoietic cell lines examined were negative for HLA-ABC, and all three of these cell lines were negative for both HLA-DR and CIITA expression. Furthermore, CIITA cDNA was transfected into K562 cells, which were negative for HLA-ABC, -DR and -DQ, but positive for HLA-DP. The transfection rendered HLA-DR negative to positive and increased the expression level of HLA-DP, but HLA-DQ remained negative. In addition to HLA-DR, HLA-ABC was also induced to express by the transfection of CIITA gene. The present study demonstrated that the expression of HLA-DR in hematopoietic cells is regulated in subordination to CIITA and the expression of HLA-DR (and HLA-ABC in K562) is induced by transfection with the CIITA gene. These findings revealed the applicability of CIITA in potentiating anti-tumour immunity of HLA-DR negative tumour cells for immunotherapy of hematological malignancies.
authors.affiliation: First Department of Internal Medicine, School of Medicine, Niigata University, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Liu
authors.forename: M
authors.initials: M
authors.lastname: Takahashi
authors.forename: K
authors.initials: K
authors.lastname: Toba
authors.forename: Z
authors.initials: Z
authors.lastname: Zheng
authors.forename: S
authors.initials: S
authors.lastname: Hashimoto
authors.forename: K
authors.initials: K
authors.lastname: Nikkuni
authors.forename: T
authors.initials: T
authors.lastname: Furukawa
authors.forename: T
authors.initials: T
authors.lastname: Koike
authors.forename: Y
authors.initials: Y
authors.lastname: Aizawa
mesh_terms: D000208:Acute Disease; D000951:Antigens, Neoplasm / Q000096:biosynthesis* / Q000235:genetics; D002051:Burkitt Lymphoma / Q000235:genetics / Q000473:pathology; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology; D015973:Gene Expression Regulation, Leukemic / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D005805:Genes, MHC Class I; D005802:Genes, MHC Class II; D006680:HLA Antigens / Q000096:biosynthesis* / Q000235:genetics; D019337:Hematologic Neoplasms / Q000235:genetics* / Q000473:pathology; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D020014:K562 Cells; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics / Q000473:pathology; D007951:Leukemia, Myeloid / Q000235:genetics / Q000473:pathology; D008224:Lymphoma, Follicular / Q000235:genetics / Q000473:pathology; D009687:Nuclear Proteins; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics / Q000473:pathology; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D012334:RNA, Neoplasm / Q000096:biosynthesis / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000502:physiology; D000071701:Regulatory Factor X Transcription Factors; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015534:Trans-Activators / Q000235:genetics / Q000502:physiology*; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D000951:Antigens, Neoplasm; D004268:DNA-Binding Proteins; D006680:HLA Antigens; C083728:MHC class II transactivator protein; D009687:Nuclear Proteins; C093524:RFX5 protein, human; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D011993:Recombinant Fusion Proteins; D000071701:Regulatory Factor X Transcription Factors; D015534:Trans-Activators; D007371:Interferon-gamma