In Vivo Optical Imaging for Immune Response

Abstract

Cells of the immune system play a critical role in defence against invading microorganisms. Conventional histological analysis can provide protein expression level better than cell morphology and location. In contrast, intravital imaging shows a great potential in monitoring the dynamic process of the immune response, from cell–cell interactions to cell–molecule interactions. In particular, in vivo optical imaging can track the dynamics of the immune response with high spatiotemporal resolution. This article introduces the development of in vivo optical imaging for immune responses in various tissues and organs, using different imaging windows. Key Concepts Immune response is a physiological process of the immune system against antigen stimulation. It is a complicated dynamic response including activation of immune cells and the effect of immune‐mediated factors. Intravital multiphoton imaging has the advantages of lower photobleaching and phototoxicity, deeper imaging depth and subcellular resolution, which is a significant tool for visualisation of cell–cell and cell–molecule interactions under pathophysiologic conditions. Microglia, as a sentinel, participate in the immune response of the brain, whose immune behaviour plays an important role in the brain function and brain diseases. Skin has essential immunological functions as the first line of defence against foreign antigen challenges, which is an ideal organ to study the immune response due to its accessibility. Tissue optical clearing methods can effectively improve optical imaging resolution and depth, which have shown a great potential in immunology research.