RT Journal Article
SR Electronic
T1 TLR3-Specific Double-Stranded RNA Oligonucleotide Adjuvants Induce Dendritic Cell Cross-Presentation, CTL Responses, and Antiviral Protection
JF The Journal of Immunology
JO J. Immunol.
FD American Association of Immunologists
SP 2422
OP 2429
DO 10.4049/jimmunol.1002845
VO 186
IS 4
A1 Jelinek, Ivett
A1 Leonard, Joshua N.
A1 Price, Graeme E.
A1 Brown, Kevin N.
A1 Meyer-Manlapat, Anna
A1 Goldsmith, Paul K.
A1 Wang, Yan
A1 Venzon, David
A1 Epstein, Suzanne L.
A1 Segal, David M.
YR 2011
UL http://www.jimmunol.org/content/186/4/2422.abstract
AB Maturation of dendritic cells (DC) to competent APC is essential for the generation of acquired immunity and is a major function of adjuvants. dsRNA, a molecular signature of viral infection, drives DC maturation by activating TLR3, but the size of dsRNA required to activate DC and the expression patterns of TLR3 protein in DC subsets have not been established. In this article, we show that cross-priming CD8α+ and CD103+ DC subsets express much greater levels of TLR3 than other DC. In resting DC, TLR3 is located in early endosomes and other intracellular compartments but migrates to LAMP1+ endosomes on stimulation with a TLR3 ligand. Using homogeneous dsRNA oligonucleotides (ONs) ranging in length from 25 to 540 bp, we observed that a minimum length of ∼90 bp was sufficient to induce CD86, IL-12p40, IFN-β, TNF-α, and IL-6 expression, and to mature DC into APC that cross-presented exogenous Ags to CD8+ T cells. TLR3 was essential for activation of DC by dsRNA ONs, and the potency of activation increased with dsRNA length and varied between DC subsets. In vivo, dsRNA ONs, in a size-dependent manner, served as adjuvants for the generation of Ag-specific CTL and for inducing protection against lethal challenge with influenza virus when given with influenza nucleoprotein as an immunogen. These results provide the basis for the development of TLR3-specific adjuvants capable of inducing immune responses tailored for viral pathogens.