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DCs facilitate B cell responses against microbial DNA via DC-SIGN.

ABSTRACT: Microbial DNA is highly immunostimulatory and is sensed by endosomal pattern recognition receptors after release from internalized microbes. It is unclear how extracellular DNA released from dead microbes is delivered to endosomal PRRs to induce immune responses. Here we have investigated the ability of DCs to bind and internalize extracellular E.coli DNA as well as synthetic DNA. DCs internalized E.coli and synthetic DNA, which was dependent on the C-type lectin receptor DC-SIGN. Notably, endosomal uptake of DNA by DCs enhanced TLR9-dependent responses of B cells against DNA. Hence, we have identified DC-SIGN as a cell surface receptor for DNA that facilitates immune responses directed against DNA.

SUBMITTER: Sprokholt JK

PROVIDER: S-EPMC5627929 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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DCs facilitate B cell responses against microbial DNA via DC-SIGN.

Sprokholt Joris K JK Heineke Marieke H MH Kaptein Tanja M TM van Hamme John L JL Geijtenbeek Teunis B H TBH

PloS one 20171004 10

Microbial DNA is highly immunostimulatory and is sensed by endosomal pattern recognition receptors after release from internalized microbes. It is unclear how extracellular DNA released from dead microbes is delivered to endosomal PRRs to induce immune responses. Here we have investigated the ability of DCs to bind and internalize extracellular E.coli DNA as well as synthetic DNA. DCs internalized E.coli and synthetic DNA, which was dependent on the C-type lectin receptor DC-SIGN. Notably, endos ...[more]

PMID: 28976999

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