Institute of Molecular and Clinical Immunology, Health Campus Immunology Infectiology and Inflammation (GC-I3), Otto-von-Guericke-University, 39120, Magdeburg, Germany.
Intravital Microscopy of Infection and Immunity, Helmholtz Centre for Infection Research, 38124, Braunschweig, Germany.
Cytometry A. 2020 May;97(5):458-470. doi: 10.1002/cyto.a.23938. Epub 2019 Nov 27.
During infections, interactions between host immune cells and the pathogen occur in distinct anatomical locations and along defined time scales. This can best be assessed in the physiological context of an infection in the living tissue. Consequently, intravital imaging has enabled us to dissect the critical phases and events throughout an infection in real time in living tissues. Specifically, advances in visualizing specific cell types and individual pathogens permitted tracking the early events of tissue invasion of the pathogen, cellular interactions involved in the induction of the immune response as well the events implicated in clearance of the infection. In this respect, two vantage points have evolved since the initial employment of this technique in the field of infection biology. On the one hand, strategies acquired by the pathogen to establish within the host and circumvent or evade the immune defenses have been elucidated. On the other hand, analyzing infections from the immune system's perspective has led to insights into the dynamic cellular interactions that are involved in the initial recognition of the pathogen, immune induction as well as effector function delivery and immunopathology. Furthermore, an increasing interest in probing functional parameters in vivo has emerged, such as the analysis of pathogen reactivity to stress conditions imposed by the host organism in order to mediate clearance upon pathogen encounter. Here, we give an overview on recent intravital microscopy findings of host-pathogen interactions along the course of an infection, from both the immune system's and pathogen's perspectives. We also discuss recent developments and future perspectives in extracting intravital information beyond the localization of pathogens and their interaction with immune cells. Such reporter systems on the pathogen's physiological state and immune cell functions may prove useful in dissecting the functional dynamics of host-pathogen interactions. © 2019 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.
在感染过程中，宿主免疫细胞与病原体之间的相互作用发生在不同的解剖位置，并沿着确定的时间尺度进行。在活体组织中的感染生理环境中，这一点可以得到最好的评估。因此，活体成像使我们能够实时在活体组织中剖析感染过程中的关键阶段和事件。具体而言，在可视化特定细胞类型和单个病原体方面的进展，使得我们能够追踪病原体对组织入侵的早期事件、参与诱导免疫反应的细胞相互作用以及清除感染的事件。在这方面，自从该技术在感染生物学领域最初应用以来，已经出现了两个有利的观点。一方面，阐明了病原体在宿主中建立并规避或逃避免疫防御的策略。另一方面，从免疫系统的角度分析感染，导致人们深入了解涉及病原体初始识别、免疫诱导以及效应功能传递和免疫病理学的动态细胞相互作用。此外，人们越来越关注在体内探测功能参数，例如分析病原体对宿主生物体施加的应激条件的反应性，以便在遇到病原体时介导清除。在这里，我们从免疫系统和病原体的角度概述了感染过程中宿主-病原体相互作用的最新活体显微镜研究结果。我们还讨论了在提取活体信息方面的最新进展和未来展望，这些信息超出了病原体的定位及其与免疫细胞的相互作用。此类关于病原体生理状态和免疫细胞功能的报告系统可能有助于剖析宿主-病原体相互作用的功能动态。
