title: Modification of human embryonic stem cell-derived dendritic cells with mRNA for efficient antigen presentation and enhanced potency.
abstract: OBJECTIVE
  Dendritic cell (DC)-based vaccines are designed to exploit the intrinsic capacity of these highly effective antigen presenting cells to prime and boost antigen-specific T-cell immune responses. Successful development of DC-based vaccines will be dependent on the ability to utilize and harness the full potential of these potent immune stimulatory cells. Recent advances to generate DCs derived from human embryonic stem cells (hESCs) that are suitable for clinical use represent an alternative strategy from conventional approaches of using patient-specific DCs. Although the differentiation of hESC-derived DCs in serum-free defined conditions has been established, the stimulatory potential of these hESC-derived DCs have not been fully evaluated.
  
  
  METHODS
  hESC-derived DCs were differentiated in serum-free defined culture conditions. The delivery of antigen into hESC-derived DCs was investigated using mRNA transfection and replication-deficient adenoviral vector transduction. hESC-derived DCs modified with antigen were evaluated for their capacity to stimulate antigen-specific T-cell responses with known HLA matching. Since IL-12 is a key cytokine that drives T-cell function, further enhancement of DC potency was evaluated by transfecting mRNA encoding the IL-12p70 protein into hESC-derived DCs.
  
  
  RESULTS
  The transfection of mRNA into hESC-derived DCs was effective for heterologous protein expression. The efficiency of adenoviral vector transduction into hESC-derived DCs was poor. These mRNA-transfected DCs were capable of stimulating human telomerase reverse transcriptase antigen-specific T cells composed of varying degrees of HLA matching. In addition, we observed the transfection of mRNA encoding IL-12p70 enhanced the T-cell stimulation potency of hESC-derived DCs.
  
  
  CONCLUSIONS
  These data provide support for the development and modification of hESC-derived DCs with mRNA as a potential strategy for the induction of T-cell-mediated immunity.
authors.affiliation: Geron Corporation, 230 Constitution Drive, Menlo Park, CA 94025, USA. knishimoto@geron.com
authors.forename: Kevin P
authors.initials: KP
authors.lastname: Nishimoto
authors.forename: Su-Yi
authors.initials: SY
authors.lastname: Tseng
authors.forename: Jane S
authors.initials: JS
authors.lastname: Lebkowski
authors.forename: Anita
authors.initials: A
authors.lastname: Reddy
mesh_terms: D000256:Adenoviridae / Q000187:drug effects / Q000235:genetics; D017951:Antigen Presentation / Q000187:drug effects / Q000235:genetics* / Q000276:immunology*; D002460:Cell Line; D003713:Dendritic Cells / Q000166:cytology / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D000939:Epitopes / Q000276:immunology; D005786:Gene Expression Regulation / Q000187:drug effects; D005822:Genetic Vectors / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006650:Histocompatibility Testing; D006801:Humans; D007156:Immunologic Memory / Q000187:drug effects / Q000276:immunology; D007371:Interferon-gamma / Q000378:metabolism; D018664:Interleukin-12 / Q000235:genetics / Q000378:metabolism; D008213:Lymphocyte Activation / Q000187:drug effects / Q000276:immunology; D010455:Peptides / Q000494:pharmacology; D010641:Phenotype; D010750:Phosphoproteins / Q000276:immunology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D014161:Transduction, Genetic; D014162:Transfection; D014763:Viral Matrix Proteins / Q000276:immunology
chemical_list: D000939:Epitopes; D010455:Peptides; D010750:Phosphoproteins; D012333:RNA, Messenger; D014763:Viral Matrix Proteins; C065418:cytomegalovirus matrix protein 65kDa; D049452:Green Fluorescent Proteins; D018664:Interleukin-12; D007371:Interferon-gamma