Phosphorothioate cap analogs increase stability and translational efficiency of RNA vaccines in immature dendritic cells and induce superior immune responses in vivo.
Vaccination with in vitro transcribed RNA coding for tumor antigens is considered a promising approach for cancer immunotherapy and has already entered human clinical testing. One of the basic objectives for development of RNA as a drug is the optimization of immunobioavailability of the encoded antigen in vivo. By analyzing the effect of different synthetic 5' mRNA cap analogs on the kinetics of the encoded protein, we found that m(2)(7,2'-O)Gpp(S)pG (beta-S-ARCA) phosphorothioate caps, in particular the D1 diastereoisomer, profoundly enhance RNA stability and translational efficiency in immature but not mature dendritic cells. Moreover, in vivo delivery of the antigen as beta-S-ARCA(D1)-capped RNA species is superior for protein expression and for efficient priming and expansion of naïve antigen-specific T cells in mice. Our findings establish 5' mRNA cap analogs as yet another module for tuning immunopharmacological properties of recombinant antigen-encoding RNA for vaccination purposes.
Kuhn
A N
AN
Division of Translational and Experimental Oncology, Department of Internal Medicine III, Johannes Gutenberg-University, Mainz, Germany.
Diken
M
M
Kreiter
S
S
Selmi
A
A
Kowalska
J
J
Jemielity
J
J
Darzynkiewicz
E
E
Huber
C
C
Türeci
O
O
Sahin
U
U
D017951:Antigen Presentation; D019496:Cancer Vaccines / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D017930:Genes, Reporter; D006207:Half-Life; D006801:Humans; D008156:Luciferases / Q000032:analysis; D054735:Phosphorothioate Oligonucleotides / Q000737:chemistry; D014176:Protein Biosynthesis; D012313:RNA / Q000737:chemistry; D012314:RNA Cap Analogs / Q000737:chemistry*; D020871:RNA Stability; D014614:Vaccines, Synthetic / Q000276:immunology / Q000378:metabolism
D019496:Cancer Vaccines; D054735:Phosphorothioate Oligonucleotides; D012314:RNA Cap Analogs; D014614:Vaccines, Synthetic; D012313:RNA; D008156:Luciferases