Endocrinology Laboratory, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany.
Institute for Evolutionary Ecology and Conservation Genomics, Ulm University, Ulm, Germany.
Am J Primatol. 2021 Dec;83(12):e23329. doi: 10.1002/ajp.23329. Epub 2021 Sep 23.
The assessment of mucosal immunity as a component of animal health is an important aspect for the understanding of variation in host immunity, and its tradeoff against other life-history traits. We investigated immunoglobulin A (IgA), the major type of antibody associated with mucosal immunity, in relation to changes in parasitic burden following anthelminthic treatment in noninvasively collected fecal samples in a semi-free ranging group of Barbary macaques (Macaca sylvanus). We measured IgA in 340 fecal samples of fourteen females and nine males. As IgA has been found to be responsive to stressors, we also related fecal IgA (fIgA) levels to fecal glucocorticoid metabolites (fGCM) measured in the same samples as part of a previous study. We found a high variability within and between individual fIgA levels over time. Running generalized additive mixed models, we found that fIgA levels were higher in males than in females, but did not change in response to the anthelmintic treatment and the resulting reduction in worm burden. Instead, fIgA level changes were significantly correlated to changes in fGCM levels. Our findings indicate that due to the strong responsiveness of fIgA to HPA-axis activity, the measurement of fIgA may have certain limitations with respect to reflecting gastrointestinal parasitic burden. Moreover, the responsiveness of fIgA to stressors interferes with the interpretation of IgA levels in fecal samples as a measure of mucosal immunity, at least in our study population of the Barbary macaques.
黏膜免疫作为动物健康的一个组成部分，是理解宿主免疫变异及其与其他生活史特征权衡的重要方面。我们研究了免疫球蛋白 A（IgA），这是与黏膜免疫相关的主要抗体类型，与驱虫治疗后半自由放养的巴巴里猕猴（Macaca sylvanus）非侵入性收集粪便样本中的寄生虫负担变化有关。我们测量了 14 只雌性和 9 只雄性的 340 个粪便样本中的 IgA。由于 IgA 已被发现对压力源有反应，我们还将粪便 IgA（fIgA）水平与在同一批样本中测量的粪便皮质激素代谢物（fGCM）相关联，这些样本是之前研究的一部分。我们发现个体内和个体间的 fIgA 水平在时间上具有很高的可变性。运行广义加性混合模型后，我们发现雄性的 fIgA 水平高于雌性，但驱虫治疗和由此导致的蠕虫负担减少并没有导致 fIgA 水平发生变化。相反，fIgA 水平的变化与 fGCM 水平的变化显著相关。我们的研究结果表明，由于 fIgA 对 HPA 轴活性的强烈反应，fIgA 的测量可能在反映胃肠道寄生虫负担方面存在一定的局限性。此外，fIgA 对压力源的反应性干扰了粪便样本中 IgA 水平作为黏膜免疫衡量指标的解释，至少在我们的巴巴里猕猴研究人群中是这样。
