Imaging Analysis & Live Cell Imaging
Live-cell imaging and analysis offer scientists the ability to study dynamic cellular events in real time, providing unique insights into cellular processes that traditional methods, such as PCR, flow cytometry, immunocytochemistry, and tissue staining with antibodies, cannot capture. Unlike these techniques, which provide static snapshots of cellular events, live-cell imaging allows for continuous observation of cellular behaviors, interactions, and changes over time. Recent advancements in camera technology, live-cell fluorescent dyes, fluorescent proteins, video compression, and time-lapse microscopy have greatly enhanced our capacity to visualize and analyze living cells, as well as their intercellular interactions and subcellular processes, with exceptional detail and precision. These advancements have revolutionized the study of cellular dynamics in a variety of research fields.
Overview
Live-cell Imaging Systems
A variety of techniques are used to visualize the complex structures and behavior of cells. In static analyses, cells are fixed and stained, which requires killing the cells and therefore capturing a single instant in cellular time. While static techniques are suitable for some applications, they do not provide insight into cellular activities. Dynamic, live-cell approaches facilitate the visualization of structure, behavior, or composition in live cells, without traditional staining. These techniques are ideal for applications that must mimic in vivo conditions, as well as for developing predictive assays for drug screening.
Live-cell imaging systems use advanced optics, environmental control, and reagents that permit long-term studies of mammalian, bacterial, and yeast cells. Culture and imaging systems that also employ microfluidics allow precise control of the culture microenvironment, like flow, gas mixture, and temperature, while limiting physical stress to cells. Live-cell imaging and analysis is suited to a range of applications, including hypoxia, cell migration, 3D cell culture, cytoskeletal dynamics, and protein trafficking. Advanced systems automate culture conditions, administration and withdrawal of treatments, and imaging intervals to create images that may be presented as still images or video data.
Live-cell Imaging Reagents
Live-cell imaging media and supplements are designed to protect cells from light-induced cellular damage during time-lapse experiments. These reagents are also formulated to have low autofluorescence and photobleaching, which dramatically enhances the quality of fluorescent live-cell images.
A variety of live-cell staining dyes are available to study the dynamic processes of live cells. Live-cell fluorescent organelle dyes permit the selective staining of specific organelles, such as the cell membrane, nucleus, cytoplasm, mitochondria, lysosomes, endoplasmic reticulum (ER), Golgi apparatus, and cytoskeleton proteins, all without increased cytotoxicity. Using organelle dyes as counterstains in live-cell imaging is also useful in functional studies.
Biosensors with GFP and RFP
Biosensors with GFP and RFP can be used to detect a specific protein as well as the subcellular location of that protein within live cells by either fluorescent microscopy or time-lapse video capture. Lentiviral vector systems are a popular tool for introducing genes and gene products into cells, with many advantages over chemical-based transfection. Beyond organelle detection, cell-permeable live-cell dyes are used for applications such as apoptosis detection, cell viability, cell health, hypoxia, reactive oxygen species studies, calcium indicator imaging, and neural or stem cell experiments.