Toll-like receptors (TLRs) represent a well-known family of conserved pattern recognition receptors the importance of which, in non-self recognition, was demonstrated in both vertebrates and invertebrates.

Tunicates represent the vertebrate sister group and, as invertebrates, they rely only on innate immunity for their defence. As regards TLRs, two transcripts have been described and characterised in the solitary species Ciona intestinalis, referred to as CiTLR1 and CiTLR2. Using the Ciona TLR nucleotide sequences, we mined our available transcriptome of the colonial ascidian Botryllus schlosseri looking for similar sequences. We were able to identify a sequence, with similarity to CiTLR2 and, through in silico transduction and subsequent sequence analysis, we studied the domain content of the putative protein. The sequence, called BsTLR1, has a TIR and a transmembrane domain, four LLR and two LRR-CT domains. It is actively transcribed by both phagocytes and morula cells, the two circulating immunocyte types. In addition, we analysed bstlr1 transcription in vivo and in vitro, in different phases of the Botryllus blastogenetic cycle and under various experimental conditions. Our data show that there is a change in gene expression and mRNA location, according to the blastogenetic phase.

Furthermore, we used a commercial antibody raised against the ectodomain of hTLR5 to study the possible functional role of Botryllus TLR(s). We observed that anti-hTLR5 significantly decreased in vitro phagocytosis and morula cell degranulation, two typical responses to the recognition of nonself.

Collectively, our data add new information on the mechanisms of nonself recognition in a colonial ascidian.

Toll样受体（TLRs）代表着一个众所周知的保守模式识别受体家族，在脊椎动物和无脊椎动物中，其非自我识别的重要性都得到了证明。

被膜代表脊椎动物的姐妹群，作为无脊椎动物，它们仅依靠先天免疫来防御。关于TLR，已经在称为CiTLR1和CiTLR2的孤独物种Ciona intestinalis的两个物种中描述并表征了两个转录物。使用Ciona TLR核苷酸序列，我们从殖民地海生Botryllus schlosseri的可用转录组中寻找相似的序列。通过计算机分析，我们能够鉴定出与CiTLR2相似的序列转导和随后的序列分析，我们研究了推定蛋白质的结构域含量。该序列称为BsTLR1，具有一个TIR和一个跨膜结构域，四个LLR和两个LRR-CT结构域。吞噬细胞和桑ula细胞这两种循环的免疫细胞类型都积极地转录它。另外，我们分析bstlr1转录在体内和体外，在不同阶段Botryllus blastogenetic周期和各种实验条件下。我们的数据显示，根据成胚期，基因表达和mRNA位置都有变化。

此外，我们使用了针对hTLR5胞外域的商业抗体来研究Botryllus TLR的可能功能。我们观察到，抗-hTLR5显着降低了体外吞噬作用和桑ula细胞脱颗粒，这是对非自我识别的两种典型反应。

总的来说，我们的数据为殖民地海床中的非自我识别机制增加了新的信息。