title: Tumor cell-specific transcription of a murine histocompatibility class Ib Q5 gene.
abstract: BACKGROUND
  We previously reported that the Q5 gene product (Q5 antigen) was expressed on the surface of various tumor cells derived from H-2k (Qa-2-) mice. The Q5 antigen has tumor-protective antigenicity in the syngeneic mice.
  
  
  METHODS
  Transcripts of the Qa region genes were analyzed by the RT-PCR method. Cell fractionation was performed with the MACS method and the phenotypes were estimated by flow cytometry analysis.
  
  
  RESULTS
  Transcripts of Q5 were produced by all tumor cell lines. The Q5 transcription was detected only in thymocytes and PBMCs of H-2k (AKR and C3H/He) mice. The phenotype of the PBMCs in which Q5 transcription takes place seems to be, at least partly, CD3-48 cells that might be related to CD3-4-8- spontaneous thymoma cells derived from an H-2k mouse.
  
  
  CONCLUSIONS
  The expression of Q5 in tumor cells in general is a result of a change of transcriptional regulation associated with malignant transformation.
authors.affiliation: Institute of Molecular Immunology, Medinet, Tamagawadai, Setagaya-ku, Tokyo 158-0096 and 2Seta Clinic, 4-20-18 Seta, Setagayaku, Tokyo 158-0095, Japan. noguchi@j-immunother.com
authors.forename: Katsuo
authors.initials: K
authors.lastname: Noguchi
authors.forename: Eri
authors.initials: E
authors.lastname: Kuwada
authors.forename: Shigenori
authors.initials: S
authors.lastname: Goto
authors.forename: Kohji
authors.initials: K
authors.lastname: Egawa
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm / Q000096:biosynthesis / Q000235:genetics*; D000954:Antigens, Surface / Q000096:biosynthesis / Q000235:genetics*; D045744:Cell Line, Tumor; D005805:Genes, MHC Class I / Q000235:genetics*; D006183:H-2 Antigens / Q000096:biosynthesis; D015395:Histocompatibility Antigens Class I / Q000096:biosynthesis / Q000235:genetics*; D008297:Male; D051379:Mice; D008806:Mice, Inbred AKR; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D009374:Neoplasms, Experimental / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D012313:RNA / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic
chemical_list: D000951:Antigens, Neoplasm; D000954:Antigens, Surface; D006183:H-2 Antigens; C108513:H-2A antigen; D015395:Histocompatibility Antigens Class I; C099538:Q5 antigen, mouse; D012313:RNA