Lipoplexes carrying mRNA encoding Gag protein modulate dendritic cells to stimulate HIV-specific immune responses.
OBJECTIVE
Cationic lipids (Lipofectamine™ [Invitrogen, Merelbeke, Belgium] and 1,2-dioleoyl-3-trimethylammonium-propane/1,2-dioleoyl-sn-glycero-3-phosphoethanolamine) and polymers (jetPEI™ and in vivo-jetPEI™ [Polyplus-transfection, Illkirch, France]) were evaluated for their potential to deliver mRNA to monocyte-derived dendritic cells.


METHODS
Lipoplexes and polyplexes, containing mRNA encoding GFP or Gag protein, were incubated with human monocyte-derived dendritic cells and transfection efficiencies were assessed by flow cytometry.


RESULTS
Lipofectamine was by far the most efficient in mRNA delivery, therefore it was used in further experiments. Incubation of monocyte-derived dendritic cells isolated from HIV-1-positive donors with mRNA encoding Gag protein complexed to Lipofectamine resulted in 50% transfection. Importantly, coculture of these Gag-transfected dendritic cells with autologous T cells induced an over tenfold expansion of IFN-γ- and IL-2-secreting CD4(+) and CD8(+) T cells.


CONCLUSIONS
Cationic lipid-mediated mRNA delivery may be a useful tool for therapeutic vaccination against HIV-1. This approach can be applied to develop vaccination strategies for other infectious diseases and cancer.
Institute of Tropical Medicine of Antwerp, Nationalestraat 155, Antwerp 2000, Belgium. wdehaes@itg.be
Winni
W
De Haes
Joanna
J
Rejman
Charlotte
C
Pollard
Céline
C
Merlin
Marc
M
Vekemans
Eric
E
Florence
Stefaan C
SC
De Smedt
Johan
J
Grooten
Guido
G
Vanham
Stefaan
S
De Koker
Ellen
E
Van Gulck
D003713:Dendritic Cells / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D015683:Gene Products, gag / Q000235:genetics*; D006678:HIV / Q000276:immunology*; D006801:Humans; D016130:Immunophenotyping; D008856:Microscopy, Fluorescence; D012333:RNA, Messenger / Q000235:genetics*
D015683:Gene Products, gag; D012333:RNA, Messenger