Dynamic pathology in various disease-model mice using multiphoton laser scanning microscopy

Live imaging of experimental animals is now possible thanks to recent technological advances that overcome the limitations of conventional histological analysis. In contrast to conventional histological microscopy techniques, this intravital approach can reveal previously unknown morphogenetic and functional processes in live tissues. In addition, this approach can capture real-time information on these processes, compared with conventional histological microscopy and other techniques that only provide snapshots in time. We used multi-photon laser-scanning microscopy (MPLSM) for in vivo real-time imaging of intra-abdominal organs, and investigated the intravital microscopic changes in various disease-model mice, referred to as ‘dynamic pathology’. For example, we used this technology to examine bacterial translocation in dextran sodium sulfate (DSS)-induced colitis, thrombus formation in laser-induced endothelial injury, neutrophil extracellular traps, the dynamics of circulating free DNA in a model of DSS-induced colitis, and to obtain a comprehensive understanding of the development and blood flow dynamics of the small intestinal microcirculation in a mouse model of necrotizing enterocolitis. This mini review summarizes the in vivo observation methods that we have developed to observe the dynamic pathology in various disease-model mice using MPLSM.