Doctorado en Acuicultura. Programa Cooperativo Universidad de Chile, Universidad Católica del Norte, Pontificia Universidad Católica de Valparaíso, Valparaiso, Chile.
Laboratorio de Genética e Inmunología Molecular, Facultad de Ciencias, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile.
Front Immunol. 2020 Nov 12;11:599625. doi: 10.3389/fimmu.2020.599625. eCollection 2020.
The interaction between host immune response and the associated microbiota has recently become a fundamental aspect of vertebrate and invertebrate animal health. This interaction allows the specific association of microbial communities, which participate in a variety of processes in the host including protection against pathogens. Marine aquatic invertebrates such as scallops are also colonized by diverse microbial communities. Scallops remain healthy most of the time, and in general, only a few species are fatally affected on adult stage by viral and bacterial pathogens. Still, high mortalities at larval stages are widely reported and they are associated with pathogenic . Thus, to give new insights into the interaction between scallop immune response and its associated microbiota, we assessed the involvement of two host antimicrobial effectors in shaping the abundances of bacterial communities present in the scallop hemolymph. To do this, we first characterized the microbiota composition in the hemolymph from non-stimulated scallops, finding both common and distinct bacterial communities dominated by the Proteobacteria, Spirochaetes and Bacteroidetes phyla. Next, we identified dynamic shifts of certain bacterial communities in the scallop hemolymph along immune response progression, where host antimicrobial effectors were expressed at basal level and early induced after a bacterial challenge. Finally, the transcript silencing of the antimicrobial peptide big defensin and the bactericidal/permeability-increasing protein by RNA interference led to an imbalance of target bacterial groups from scallop hemolymph. Specifically, a significant increase in the class Gammaproteobacteria and the proliferation of spp. was observed in scallops silenced for each antimicrobial. Overall, our results strongly suggest that scallop antimicrobial peptides and proteins are implicated in the maintenance of microbial homeostasis and are key molecules in orchestrating host-microbiota interactions. This new evidence depicts the delicate balance that exists between the immune response of and the hemolymph microbiota.
宿主免疫反应与相关微生物群落的相互作用最近已成为脊椎动物和无脊椎动物健康的一个基本方面。这种相互作用允许微生物群落的特定关联，这些群落参与宿主的各种过程，包括抵御病原体。海洋水生无脊椎动物，如扇贝，也被多样化的微生物群落所定植。扇贝大部分时间保持健康，一般来说，只有少数几种病毒和细菌病原体在成体阶段对其产生致命影响。然而，幼虫阶段的高死亡率广泛报道，并与致病性有关。因此，为了深入了解扇贝免疫反应与其相关微生物群之间的相互作用，我们评估了两种宿主抗菌效应物在塑造扇贝血淋巴中存在的细菌群落丰度方面的作用。为此，我们首先对非刺激扇贝血淋巴中的微生物群落组成进行了特征描述，发现了以变形菌门、螺旋体门和拟杆菌门为主导的常见和独特的细菌群落。接下来，我们确定了在免疫反应过程中，某些细菌群落沿扇贝血淋巴中的动态变化，其中宿主抗菌效应物在基础水平上表达，并在细菌挑战后早期诱导。最后，抗菌肽 big defensin 和杀菌/通透性增加蛋白的 RNA 干扰沉默导致扇贝血淋巴中靶细菌群的失衡。具体来说，在每种抗菌肽沉默的扇贝中，观察到类γ变形菌纲和 spp.的显著增加。总体而言，我们的结果强烈表明，扇贝抗菌肽和蛋白参与维持微生物内稳态，是协调宿主-微生物相互作用的关键分子。这一新证据描绘了扇贝和血淋巴微生物群之间存在的微妙平衡。
