title: Enhancement of immunogenicity of Jeg3 cells by ectopic expression of HLA-A*0201 and CD80.
abstract: OBJECTIVE
  The choriocarcinoma cell line Jeg3 suppresses immunity in vitro by secretion of soluble factors like leukemia inhibitory factor suppressing leukocyte activation. The cells lack expression of classical human leukocyte antigen (HLA)-A and -B alleles but express some HLA-C, and non-classical HLA-G and -E. Upon binding to killing inhibitory receptor on natural killer (NK) cells, HLA-G prevents activation of cytolytic activity. We investigated whether Jeg3 cells are capable of immune stimulation after complementation with classical HLA and T cell costimulatory signal CD80.
  
  
  METHODS
  Jeg3 cells were transduced to express HLA-A*0201 and/or CD80. Parental Jeg3 or transfectants Jeg3-A2, Jeg3-CD80 or Jeg3-CD80-A2 were used to stimulate allogeneic resting and activated peripheral blood lymphocytes (PBL). The different cell lines were loaded with a HLA-A2-restricted Epstein-Barr virus (EBV) recall antigen peptide epitope and antigen presenting ability was examined. T cell lines specific for Jeg3 and transfectants were generated from HLA-A2 matched and nonmatched donors and compared for expansion, phenotypes and cytolytic activity.
  
  
  RESULTS
  While all Jeg3 cell lines induced only marginal proliferation of resting T cells, phytohemagglutinin (PHA)-activated T cells were stimulated by CD80 or CD80-A2 expressing Jeg3. Only the transfectant Jeg3-CD80-A2 was capable of specific T cell stimulation by EBV recall antigen presentation. T cell lines of HLA-A2 non-matched donors stimulated with the Jeg3 transfectants showed significant expansion only when HLA-A2 and the costimulus CD80 were present. T cells from HLA-A2 positive donors did not expand significantly or differentially. No NK cells grew under any condition. In Jeg3-CD80-A2 stimulated T cells lines CD8+ cells expanded preferentially. These T cells exerted cytolytic activity toward all Jeg3 cell lines.
  
  
  CONCLUSIONS
  Our data suggest that, in spite of immunosuppressive mechanisms, proliferative and cytolytic T cell responses are induced by Jeg3 cells when classical HLA- and/or costimulatory signals are present on the cells.
authors: Abteilung für Frauenheilkunde, Gynäkologische Molekularbiologie, Frauenklinik, FSU Jena, Jena, Germany.
authors: Serpil
authors: S
authors: Koc
authors: Angela
authors: A
authors: Kather
authors: Udo R
authors: UR
authors: Markert
authors: Matthias
authors: M
authors: Dürst
authors: Achim
authors: A
authors: Schneider
authors: Andreas M
authors: AM
authors: Kaufmann
mesh_terms: D000938:Antigen-Presenting Cells / Q000276:immunology / Q000378:metabolism; D018122:B7-1 Antigen / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D005260:Female; D015234:HLA-A Antigens / Q000235:genetics / Q000378:metabolism*; D015789:HLA-A2 Antigen; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D014161:Transduction, Genetic
chemical_list: D018122:B7-1 Antigen; D015234:HLA-A Antigens; C435939:HLA-A*02:01 antigen; D015789:HLA-A2 Antigen