Two Photon Intravital Microscopy of Lyme Borrelia in Mice.

Two-photon intravital microscopy is a powerful tool that allows visualization of cells in intact tissues in a live animal in real time. In recent years, this advanced technology has been applied to understand pathogen-host interactions using fluorescently labeled bacteria. In particular, infectious fluorescent transformants of the Lyme disease spirochete Borrelia burgdorferi, an Ixodes tick-transmitted pathogen, have been imaged by two-photon intravital microscopy to study bacterial motility and interactions of the pathogen with feeding ticks and host tissues. Here, we describe the techniques and equipment used to image mammalian-adapted spirochetes in the skin of living mice in vivo and in joints ex vivo using two-photon intravital microscopy.