Background

Toll-Like Receptors (TLRs) play a critical role in the innate and adaptive immune system. They are the mammalian orthologs of Drosophila melanogaster protein Toll, which has been proved to have an early morphogenetic role in invertebrate embryogenesis that in the adult switches to an immune function.

Aim

The aim of this study was to evaluate the expression of TLR4 and TLR7 during dorsal root ganglia (DRG), paravertebral ganglia (PVG), and enteric nervous system (ENS) murine development.

Methods

Mouse embryos from different stages (i.e. E12 to E18) were processed for immunolocalization analysis on formalin-fixed paraffin-embedded sections, and isolated intestine were processed for whole-mount preparations.

Results

We observed a differentially regulated expression of TLR4 and TLR7 during embryogenesis and an overall increased expression of both receptors during development. While TLR4 was detectable in neurons of DRG and PVG starting from E14 and only from E18 in the ENS, TLR7 was already expressed in scattered neurons of all the investigated regions at E12.

Conclusions

TLR4 and TRL7 expression temporal patterns suggest a morphogenetic role for these receptors in the development of neural crest derivatives in mammals.

中文翻译：

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Toll样受体4和7在鼠外周神经系统发育中的表达。

背景

类似收费受体（TLR）在先天性和适应性免疫系统中起关键作用。它们是果蝇果蝇蛋白Toll的哺乳动物直系同源物，已被证明在无脊椎动物胚胎发生中具有早期形态发生作用，该成年后成年动物会转变为免疫功能。

目标

这项研究的目的是评估背根神经节（DRG），椎旁神经节（PVG）和肠神经系统（ENS）鼠发育过程中TLR4和TLR7的表达。

方法

在福尔马林固定石蜡包埋的切片上处理来自不同阶段（即E12至E18）的小鼠胚胎进行免疫定位分析，并处理分离出的肠道以进行整装制剂。

结果

我们观察到在胚胎发生过程中TLR4和TLR7的表达差异调节，并且在发育过程中两种受体的表达都总体增加。虽然从E14开始仅在ENS中的E18处可在DRG和PVG的神经元中检测到TLR4，但在E12处所有研究区域的分散神经元中已经表达了TLR7。

结论

TLR4和TRL7表达的时间模式表明这些受体在哺乳动物神经c衍生物发育中的形态发生作用。