Universidad Nacional de Córdoba, Facultad de Ciencias Exactas, Físicas y Naturales, Departamento de Diversidad Biológica y Ecología, Córdoba Capital, Córdoba, Argentina.
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Diversidad y Ecología Animal (IDEA), Laboratorio de Biología Reproductiva y Evolución, Córdoba Capital, Cordoba, Argentina.
PLoS One. 2019 Feb 11;14(2):e0208682. doi: 10.1371/journal.pone.0208682. eCollection 2019.
Immune defense is a key feature in the life history of organisms, expensive to maintain, highly regulated by individuals and exposed to physiological and evolutionary trade-offs. In chelicerates, relatively scarce are the studies that relate postcopulatory mechanisms and immune response parameters. This work makes an approximation to the female's immunological consequences produced after the placement of a foreign body in the genitalia of three scorpions species, two species that normally receive genital plugs during mating (Urophonius brachycentrus and U. achalensis) and one that does not (Zabius fuscus). Here we performed the first morphological description of the natural plugs of the two Urophonius species. We described complex three zoned structure anchored to the female genital atrium and based on this information we placed implants in the genitalia (for eliciting the local immune response) of virgin females of the three species and measured the immune encapsulation response to this foreign body. We found a greater and heterogeneous response in different zones of the implants in the plug producing species. To corroborate the specificity of this immune response, we compared the local genital reaction with the triggered response at a systemic level by inserting implants into the female body cavity of U. brachycentrus and Zabius fuscus. We found that the systemic response did not differ between species and that only in the plug producing species the local response in the genitalia was higher than the systemic one. We also compared the total hemocyte load before and after the genital implantation to see if this parameter was compromised by the immunological challenge. We confirmed that in Urophonius species the presence of a strange body in the genitalia caused a decrease in the hemocyte load. Besides, we find correlations between the body weight and the immunological parameters, as well as between different immunological parameters with each other. Complementarily, we characterized the hemocytes of the three scorpion species for the first time. This comparative study can help to provide a wider framework of the immunological characteristics of the species, their differences and their relationship with the particular postcopulatory mechanism such as the genital plugs.
免疫防御是生物生活史中的一个关键特征，维护成本高昂，受到个体的高度调节，并面临生理和进化权衡。在螯肢动物中，与交配后机制和免疫反应参数相关的研究相对较少。这项工作近似于三种蝎子物种中雌性在生殖器中放置异物后的免疫后果，其中两种物种在交配时通常会接受生殖器塞（Urophonius brachycentrus 和 U. achalensis），而另一种则没有（Zabius fuscus）。在这里，我们首次对两种 Urophonius 物种的天然塞进行了形态描述。我们描述了复杂的三分区结构，该结构锚定在雌性生殖腔，并基于此信息，我们在三种物种的处女雌性生殖器中植入植入物，并测量了对这种异物的免疫包封反应。我们发现，在产生塞的物种中，植入物的不同区域会产生更大且异质的反应。为了证实这种免疫反应的特异性，我们将 U. brachycentrus 和 Zabius fuscus 雌性生殖腔中的植入物引起的局部生殖器反应与全身水平触发的反应进行了比较。我们发现，物种间的全身反应没有差异，只有在产生塞的物种中，生殖器的局部反应高于全身反应。我们还比较了生殖器植入前后的总血细胞负荷，以确定该参数是否因免疫挑战而受损。我们证实，在 Urophonius 物种中，生殖器中存在异物会导致血细胞负荷减少。此外，我们发现体重与免疫参数之间以及不同免疫参数之间存在相关性。此外，我们首次对这三种蝎子物种的血细胞进行了特征描述。这项比较研究有助于为物种的免疫特征、它们之间的差异以及它们与生殖器塞等特定交配后机制的关系提供更广泛的框架。
