Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany.
Institute of Biology, Freie Universität Berlin, Takustr. 3, 14195, Berlin, Germany.
Sci Rep. 2022 Sep 10;12(1):15259. doi: 10.1038/s41598-022-18240-6.
The acute phase response (APR) is an evolutionarily well-conserved part of the innate immune defense against pathogens. However, recent studies in bats yielded surprisingly diverse results compared to previous APR studies on both vertebrate and invertebrate species. This is especially interesting due to the known role of bats as reservoirs for viruses and other intracellular pathogens, while being susceptible to extracellular microorganisms such as some bacteria and fungi. To better understand these discrepancies and the reservoir-competence of bats, we mimicked bacterial, viral and fungal infections in greater mouse-eared bats (Myotis myotis) and quantified different aspects of the APR over a two-day period. Individuals reacted most strongly to a viral (PolyI:C) and a bacterial (LPS) antigen, reflected by an increase of haptoglobin levels (LPS) and an increase of the neutrophil-to-lymphocyte-ratio (PolyI:C and LPS). We did not detect fever, leukocytosis, body mass loss, or a change in the overall functioning of the innate immunity upon challenge with any antigen. We add evidence that bats respond selectively with APR to specific pathogens and that the activation of different parts of the immune system is species-specific.
急性期反应（APR）是宿主固有免疫系统抵御病原体的一种进化上保守的机制。然而，与脊椎动物和无脊椎动物物种的以往 APR 研究相比，最近对蝙蝠的研究结果却出人意料地呈现出多样性。这尤其有趣，因为蝙蝠已知是病毒和其他细胞内病原体的宿主，同时又容易受到某些细菌和真菌等细胞外微生物的感染。为了更好地理解这些差异和蝙蝠的储主能力，我们在大足鼠耳蝠（Myotis myotis）中模拟了细菌、病毒和真菌感染，并在两天的时间内量化了 APR 的不同方面。个体对病毒（PolyI:C）和细菌（LPS）抗原的反应最为强烈，这反映在结合珠蛋白水平的升高（LPS）和中性粒细胞与淋巴细胞比值的升高（PolyI:C 和 LPS）。我们没有检测到发热、白细胞增多、体重减轻或任何抗原挑战时固有免疫整体功能的改变。我们提供的证据表明，蝙蝠会选择性地对特定病原体产生 APR，并且不同部分的免疫系统的激活具有物种特异性。
