Comparison of DNA- and mRNA-transfected mouse dendritic cells as potential vaccines against the human papillomavirus type 16 associated oncoprotein E7.
BACKGROUND
Dendritic cells (DCs) mediate the generation of strong cytotoxic T-lymphocyte (CTL) responses by functioning in antigen presentation and exerting adjuvant properties. We compared several activation markers and parameters of biological activity of DNA- and mRNA-transfected DCs in vitro and in vivo.


METHODS
CpG-matured, bone marrow derived C57BL/6 mouse DCs were electroporated either with enhanced green fluorescence protein (EGFP) or human papillomavirus type 16 (HPV16) E7 expression plasmids or in vitro transcribed mRNAs encoding for the codon-optimized E7 or a shuffled version thereof. Activation marker expression and antigen presentation was analysed by fluorescence-activated cell sorting. The migratory behaviour of transfected DCs were investigated by in vitro chemotaxis experiments and cytokine expression by ELISA. CTL-priming capacity of transfected DCs were determined by vaccination of mice.


RESULTS
mRNA transfection produced a two- to fourfold increase of the activation markers CD40, CD80, CD86 and MHC I and MHC II molecules. Predominately antigen-expressing DCs migrated after mRNA transfection. Furthermore, mRNA-transfected DCs were capable of inducing a chemokine gradient. After maturation, electroporation and activation with soluble CD40 ligand and interferon-y, DCs displayed a T-helper cell type 2 cytokine expression pattern. Nevertheless, E7-transfected DCs were able to prime E7-specific CTL responses in vivo. The highest E7-specific CTL frequencies were found in mice immunized with mRNA-transfected DCs. The in vitro expanded CTLs exerted functional E7-specific cytotoxic activity.


CONCLUSIONS
Genetically modified DCs are suitable vehicles for the induction of E7-specific CTL responses in mice and hence could help to eradicate HPV-associated lesions in humans.
Dell
Kerstin
K
German Cancer Research Center (DKFZ), Heidelberg, Germany.
Klein
Corinna
C
Gissmann
Lutz
L
D000818:Animals; D017951:Antigen Presentation; D001854:Bone Marrow Cells / Q000276:immunology; D004279:DNA, Viral / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D018274:Electroporation; D005260:Female; D049452:Green Fluorescent Proteins / Q000235:genetics; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D009856:Oncogene Proteins, Viral / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D050725:Papillomavirus E7 Proteins; D053918:Papillomavirus Vaccines / Q000235:genetics / Q000276:immunology*; D010957:Plasmids; D012333:RNA, Messenger / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014162:Transfection
D004279:DNA, Viral; D009856:Oncogene Proteins, Viral; D050725:Papillomavirus E7 Proteins; D053918:Papillomavirus Vaccines; D012333:RNA, Messenger; C059731:oncogene protein E7, Human papillomavirus type 16; D049452:Green Fluorescent Proteins