title: Optimizing the process of nucleofection for professional antigen presenting cells.
abstract: BACKGROUND
  In times of rapidly increasing numbers of immunological approaches entering the clinics, antigen delivery becomes a pivotal process. The genuine way of rendering antigen presenting cells (APC) antigen specific, largely influences the outcome of the immune response. Short peptides bear the demerit of HLA restriction, whereas the proper way of delivery for long peptide sequences is currently a matter of debate. Electroporation is a reliable method for antigen delivery, especially using nucleic acids. The nucleofection process is based on this approach with the twist of further ensuring delivery also into the nucleus. Beside the form of antigen, the type of APC used for immune response induction may be crucial. Dendritic cells (DC) are by far the most commonly used APC; however B cells have entered this field as well and have gained wide acceptance.
  
  
  RESULTS
  In this study, we compared B cells to DC with regard to nucleofection efficiency and intensity of resulting antigen expression. APC were transfected either with plasmid DNA containing the reporter gene green fluorescent protein (GFP) or directly with in vitro-transcribed (IVT) GPF mRNA as a surrogate antigen. Out of nearly 100 different nucleofection programs tested, the top five for each cell type were identified and validated using cells from cancer patients. Flow cytometric analyses of transfected cells determining GFP expression and viability revealed a reverse correlation of efficiency and viability. Finally, donor dependant variances were analyzed.
  
  
  CONCLUSIONS
  In summary, nucleofection of both DC and B cells is feasible with plasmid DNA and IVT mRNA. And no differences with regard to nucleofectability were observed between the two cell types. Using IVT mRNA omits the danger of genomic integration and plasmid DNA constructs permit a more potent and longer lasting antigen expression.
authors.affiliation: Molecular Oncology and Immunotherapy, Department of General Surgery, University Hospital Rostock, Schillingallee 35, 18057, Rostock, Germany. christina.mullins@uni-rostock.de.|University Children's Hospital Rostock, Ernst-Heydemann-Str. 8, 18057, Rostock, Germany. christina.mullins@uni-rostock.de.
authors.forename: Christina Susanne
authors.initials: CS
authors.lastname: Mullins
authors.affiliation: Molecular Oncology and Immunotherapy, Department of General Surgery, University Hospital Rostock, Schillingallee 35, 18057, Rostock, Germany. tabea.wegner@med.uni-rostock.de.
authors.forename: Tabea
authors.initials: T
authors.lastname: Wegner
authors.affiliation: Molecular Oncology and Immunotherapy, Department of General Surgery, University Hospital Rostock, Schillingallee 35, 18057, Rostock, Germany. ernst.klar@med.uni-rostock.de.
authors.forename: Ernst
authors.initials: E
authors.lastname: Klar
authors.affiliation: University Children's Hospital Rostock, Ernst-Heydemann-Str. 8, 18057, Rostock, Germany. carl-friedrich.classen@med.uni-rostock.de.
authors.forename: Carl-Friedrich
authors.initials: CF
authors.lastname: Classen
authors.affiliation: Molecular Oncology and Immunotherapy, Department of General Surgery, University Hospital Rostock, Schillingallee 35, 18057, Rostock, Germany. michael.linnebacher@med.uni-rostock.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Linnebacher
mesh_terms: D001402:B-Lymphocytes / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D003713:Dendritic Cells / Q000378:metabolism* / Q000473:pathology; D018274:Electroporation; D005434:Flow Cytometry; D015870:Gene Expression; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D010957:Plasmids / Q000737:chemistry / Q000378:metabolism; D061251:Primary Cell Culture; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D014162:Transfection / Q000379:methods*
chemical_list: D012333:RNA, Messenger; D049452:Green Fluorescent Proteins