CD14 is not involved in the uptake of synthetic CpG oligonucleotides

Abstract

We have previously shown that DEC205, a surface receptor expressed at high levels on CD8+DC, is able to capture synthetic CpG oligonucleotides (ODN) and is required for optimal responsiveness. However, even in the absence of DEC205, CD8+DC are able to respond to CpG ODN, albeit suboptimally. This suggested that additional receptors might contribute to the uptake of CpG ODN. CD14 represented an ideal candidate as it is expressed by DC and has been shown to bind and facilitate the uptake of CpG ODN. However, when CD14-deficient (CD14−/−) mice and normal B6 mice were injected with CpG ODN, CD8+DC were equivalently activated as assessed by the upregulation of the co-stimulatory molecules CD40 an..