Campbell Shonda M, Starz-Gaiano Michelle, Leips Jeff
Department of Biology, University of Maryland Baltimore County.
Department of Biology, University of Maryland Baltimore County;
J Vis Exp. 2020 Jun 11(160). doi: 10.3791/60983.
Phagocytosis is an essential function of the innate immune response. This process is carried out by phagocytic hemocytes whose primary function is to recognize a wide range of particles and destroy microbial pathogens. As organisms age, this process begins to decline, yet little is known about the underlying mechanisms or the genetic basis of immunosenescence. Here, an injection based in vivo phagocytosis assay is used to assess age related changes in different aspects of phagocytosis, such as binding, engulfment, and degradation of internalized particles, by quantifying phagocytic events in hemocytes in adult Drosophila. Drosophila melanogaster has become an ideal model to investigate age related changes in innate immune function for many reasons. For one, many genetic components and functions of the innate immune response, including phagocytosis, are evolutionarily conserved between Drosophila and mammals. Because of that, results obtained from using this protocol are likely to be widely relevant to understanding the age related changes in immune function in a variety of organisms. Additionally, we note that this method provides quantitative estimates of hemocyte phagocytic ability, which could be useful for a variety of research topics, and need not be limited to studies of aging.
吞噬作用是先天性免疫反应的一项基本功能。这一过程由吞噬血细胞执行，其主要功能是识别多种颗粒并摧毁微生物病原体。随着生物体衰老，这一过程开始衰退，但对于免疫衰老的潜在机制或遗传基础却知之甚少。在此，通过对成年果蝇血细胞中的吞噬事件进行定量分析，一种基于注射的体内吞噬分析方法被用于评估吞噬作用不同方面与年龄相关的变化，如内化颗粒的结合、吞噬和降解。黑腹果蝇已成为研究先天性免疫功能与年龄相关变化的理想模型，原因有很多。其一，先天性免疫反应的许多遗传成分和功能，包括吞噬作用，在果蝇和哺乳动物之间具有进化保守性。因此，使用该方案获得的结果可能与理解多种生物体免疫功能与年龄相关的变化广泛相关。此外，我们注意到该方法提供了血细胞吞噬能力的定量估计，这可能对各种研究课题有用，并且不必局限于衰老研究。
