{"id":455212,"date":"2020-10-07T19:02:49","date_gmt":"2020-10-07T23:02:49","guid":{"rendered":"http:\/\/www.rochester.edu\/newscenter\/?p=455212"},"modified":"2021-12-02T11:21:47","modified_gmt":"2021-12-02T16:21:47","slug":"imaging-the-secret-lives-of-immune-cells-in-the-eye-455212","status":"publish","type":"post","link":"https:\/\/www.rochester.edu\/newscenter\/imaging-the-secret-lives-of-immune-cells-in-the-eye-455212\/","title":{"rendered":"Imaging the secret lives of immune cells in the eye"},"content":{"rendered":"
Rochester researchers demonstrate way to track the interactions of microscopic immune cells in a living eye without dyes or damage, a first for imaging science.<\/div>\n

<\/p>\n

<\/p>\n

Combining infrared videography and artificial intelligence, the new technique could be a \u2018game-changer\u2019 for some clinical diagnoses as well as for fields like pharmaceuticals.<\/div>\n

<\/p>\n

Ä¢¹½´«Ã½<\/a> vision scientist Jesse Schallek<\/a> can barely contain his excitement as he shares time-lapse videos showing immune cells moving through living retinal tissue at the back of an eye.<\/p>\n

In one clip, immune cells crawl so slowly along the inside edge of a blood vessel that the video must be sped up 25 times to show their progress. Another cell slowly treads against the flow of blood in a vessel, like a salmon fighting its way upstream. Other immune cells leave the blood vessels and inch through the surrounding tissue, then congregate in a swarm, forming a beehive of activity.<\/p>\n

Schallek and his vision lab at the URochester Center for Visual Science<\/a> and Flaum Eye Institute<\/a>, have created a new microscopy technique, described in the journal eLIFE<\/a>, that builds upon groundbreaking adaptive optics developed at the University more than 20 years ago.<\/p>\n

Combined with time lapse videography and artificial intelligence software, the new technique enables researchers for the first time to noninvasively image and track\u2014without labeling\u2014the interactions of translucent immune cells within live retinal tissue in animals. Until now, the immune cells had to be labeled with fluorescent agents and often reinjected in order to image them\u2014raising questions about how this might change the behavior of the cells. Another common, but limiting approach is to remove cells and study them with a microscope in a dish.<\/p>\n

\n
\n
https:\/\/www.rochester.edu\/newscenter\/wp-content\/uploads\/2020\/10\/detail_of_single_immune_Cell_behavior.mp4<\/a><\/video><\/div>\n<\/div>\n

CELLULAR DETAILS<\/strong>: Using the new techique, researchers in the lab of Rochester vision scientist Jesse Shallek captured images of the same retinal location and tracked it over two months as the area responded to injury. Single immune cells arrive and respond with vigor at 6 hours and 24 hours after the injury. The retina then returns to normal conditions after weeks to months (Courtesy of Schallek lab)<\/p>\n

\n

Schallek\u2019s lab avoids both complications by imaging immune cells in the living eye without requiring dyes at all\u2014the first study of its kind to do so.<\/p>\n

\u201cWe think of the eye as this beautiful window where we can peer in, noninvasively, without having to cut or insert a camera into places where we would rather it didn\u2019t go,\u201d says Schallek, an assistant professor of ophthalmology and neuroscience.<\/p>\n

\u201cThe eye is an extension of our brain, and therefore with this technology we have some of our first glimpses into immune cell function deep in the central nervous system. This is a critical step forward for basic science and clinical study alike.\u201d<\/p>\n

Schallek\u2019s lab is now adapting the new technique for use with human patients.<\/p>\n

\u201cWe think this will be a game changer for ophthalmology and for our understanding of retinal diseases that lead to blindness,\u201d says Schallek.<\/p>\n

What role do immune cells play in inflammation?<\/h2>\n

Immune cells are at the center of \u201ca whole cascade of events\u201d that cause the inflammation that is characteristic of most retinal eye diseases that lead to blindness, Schallek says. For example, in addition to immune cells arriving at the affected tissue, and releasing compounds that recruit more immune cells, there are also changes in blood flow\u2014all of which interfere with vision and complicate the progression of the disease.<\/p>\n

Until now, the tools available to measure inflammation in retinal tissue have been limited.<\/p>\n

<\/p>\n

\n

What is adaptive optics?<\/h2>\n

The new imaging technique draws on adaptive optics, a process developed by astronomers to take clear pictures of the sky without distortions from Earth\u2019s atmosphere. Rochester vision scientist David Williams pioneered the use of adaptive optics to obtain very sharp images from inside the eye. More about adaptive optics<\/a><\/p>\n<\/div>\n

<\/p>\n

Optical coherence tomography, for example, has been used to measure the thickness of retinal tissue at the back of the eye. \u201cThe thickness of that tissue is thought to be a marker for how inflamed the tissue is,\u201d Schallek says. \u201cHowever useful that might be, it doesn\u2019t really tell you what the cells in that tissue are doing.\u201d<\/p>\n

The new technology developed by his lab does that by:<\/p>\n