Piccio-Wu Two Photon Microscopy Videos

Video 1 -Pre-Onset EAE


In vivo two-photon imaging of the mouse spinal cord during pre-clinical active EAE. A CX3CR1GFP x CD11YFP mouse was immunized with MOG35-55 to induce active EAE and the spinal cord was imaged in vivo before the clinical onset of the disease (clinical score = 0). Microglia/macrophages are in blue, dendritic cells (DCs) are in green and in red is a blood vessel. Notably, at this stage of the disease innate immune cells are highly dynamic within the tissue. Along with probing behavior, movement of DCs and some microglia/macrophages can be easly appreciated within the spinal cord white matter and around the vessel.


Video 2 – Clinical EAE


In vivo two-photon imaging of the mouse spinal cord after onset of active EAE. A CX3CR1GFP x CD11YFP mouse was immunized with MOG35-55 to induce active EAE and the spinal cord was imaged in vivo after onset of EAE (clinical score = 2). Microglia/macrophages are in blue, dendritic cells (DCs) are in green and in red is a blood vessel. Innate immune cells within the spinal cord during clinical EAE have assumed a more ramified shape and appear less dynamic compared to pre-onset.


Video 3 -In vivo imaging of axons


In vivo two-photon imaging of the spinal cord in a naïve CX3CR1GFP x Thy1YFP mouse. The images were taken through an intervertebral window to preserve the integrity of the meninges. Axons are in green, microglia/macrophages in blue and in red is a blood vessel. Innate immune cells are adjacent to axons in a resting condition.


Video 4 – Innate immune cells and axonal damage in EAE


Two-photon microscopy imaging of the interactions between innate immune cells (microglia/macrophages and dendritic cells) with damaged axons in the spinal cord during experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis. Axons (visualized in yellow) exhibit extensive damage during EAE, with the presence of spheroidal axonal bulbs that are indicative of severe, acute axonal injury. Microglia/macrophages (labeled in blue) were often seen in close proximity to damaged axons and in one case they were apparently engulfing part of an axon (bottom left of the image). Fluorescently labeled dendritic cells (DCs in red) were transferred two days prior to imaging. DCs migrated into the CNS where they could be visualized in areas of inflammatory injury in the spinal cord. In some instances, DCs were observed in close association to axons. We are currently seeking the possible role of innate immune cells in myelin and axonal damage during EAE and possibly MS.


Video 5 – Mouse Cells Moving in a Tissue


Imaging using two-photon microscopy of encephalitogenic MOG35-55 specific T lymphocytes (blue, due to expression of cyanin fluorescent protein) in the spinal cord during experimental autoimmune encephalomyelitis, a model for multiple sclerosis. MOG specific T lymphocytes move rapidly within the CNS parenchyma searching for their target antigen. Some activated T cells create brief contacts with microglial cells (green, due to green fluorescent protein expression), while others establish more stable interactions with microglia. Because microglia function as antigen presenting cells in the central nervous system, these more stable interactions between T lymphocytes and microglia are considered to represent antigen recognition events. A rhodamine dextran labeled blood vessel appears red.