Ian A Sigal1, Jessica Steele2, Scott Drexler2, Kira L Lathrop3. 1. University of Pittsburgh School of Medicine, Department of Ophthalmology, Pittsburgh, Pennsylvania, USA; University of Pittsburgh Swanson School of Engineering, Department of Bioengineering, Pittsburgh, Pennsylvania, USA. 2. University of Pittsburgh School of Medicine, Department of Ophthalmology, Pittsburgh, Pennsylvania, USA. 3. University of Pittsburgh School of Medicine, Department of Ophthalmology, Pittsburgh, Pennsylvania, USA; University of Pittsburgh Swanson School of Engineering, Department of Bioengineering, Pittsburgh, Pennsylvania, USA. Electronic address: lathropkl@upmc.edu.
Abstract
PURPOSE: The Palisades of Vogt (POV) constitute the corneal epithelial stem cell niche, but identification of this region in ex vivo tissue is difficult. Here we introduce a simple, direct method of identifying the POV in unsectioned, ex vivo human tissue. METHODS: Twenty-two eyes were studied, four whole and eighteen rims. Orientation of whole eyes was determined and the eyes were marked to maintain their cardinal orientation prior to dissection. Samples were imaged with brightfield, linearly polarized light and transmitted circularly polarized light (CPL), and optical coherence tomography (OCT) volumes were acquired in all twelve clock hrs around the limbus. Five samples were also fluorescently labeled to identify the epithelial basement membrane, and whole mounts were imaged with laser scanning confocal microscopy. Images were compared to confirm that the structures visible with polarized light were POV. RESULTS: Under CPL the POV presented as amber radial ridges visible in the superior and inferior regions of the tissue. Identification of POV was confirmed by correlating the structures seen under CPL, OCT and laser-scanning confocal microscopy. CONCLUSIONS: CPL can be used to quickly identify POV regions in donor tissue. This technique can assist in targeted harvesting of stem cell regions for research and tissue for limbal transplant.
PURPOSE: The Palisades of Vogt (POV) constitute the corneal epithelial stem cell niche, but identification of this region in ex vivo tissue is difficult. Here we introduce a simple, direct method of identifying the POV in unsectioned, ex vivo human tissue. METHODS: Twenty-two eyes were studied, four whole and eighteen rims. Orientation of whole eyes was determined and the eyes were marked to maintain their cardinal orientation prior to dissection. Samples were imaged with brightfield, linearly polarized light and transmitted circularly polarized light (CPL), and optical coherence tomography (OCT) volumes were acquired in all twelve clock hrs around the limbus. Five samples were also fluorescently labeled to identify the epithelial basement membrane, and whole mounts were imaged with laser scanning confocal microscopy. Images were compared to confirm that the structures visible with polarized light were POV. RESULTS: Under CPL the POV presented as amber radial ridges visible in the superior and inferior regions of the tissue. Identification of POV was confirmed by correlating the structures seen under CPL, OCT and laser-scanning confocal microscopy. CONCLUSIONS: CPL can be used to quickly identify POV regions in donor tissue. This technique can assist in targeted harvesting of stem cell regions for research and tissue for limbal transplant.
Authors: Kira L Lathrop; Divya Gupta; Larry Kagemann; Joel S Schuman; Nirmala Sundarraj Journal: Invest Ophthalmol Vis Sci Date: 2012-03-15 Impact factor: 4.799
Authors: Ning-Jiun Jan; Jonathan L Grimm; Huong Tran; Kira L Lathrop; Gadi Wollstein; Richard A Bilonick; Hiroshi Ishikawa; Larry Kagemann; Joel S Schuman; Ian A Sigal Journal: Biomed Opt Express Date: 2015-11-05 Impact factor: 3.732
Authors: Craig Boote; Erin P Dooley; Steven J Gardner; Christina S Kamma-Lorger; Sally Hayes; Kim Nielsen; Jesper Hjortdal; Thomas Sorensen; Nicholas J Terrill; Keith M Meek Journal: PLoS One Date: 2013-09-24 Impact factor: 3.240