P-Cadherin Is Expressed by Epithelial Progenitor Cells and Melanocytes in the Human Corneal Limbus

Interactions between limbal epithelial progenitor cells (LEPC) and surrounding niche cells, which include limbal mesenchymal stromal cells (LMSC) and melanocytes (LM), are essential for the maintenance of the limbal stem cell niche required for a transparent corneal surface. P-cadherin (P-cad) is a critical stem cell niche adhesion molecule at various epithelial stem cell niches; however, conflicting observations were reported on the presence of P-cad in the limbal region. To explore this issue, we assessed the location and phenotype of P-cad+ cells by confocal microscopy of human corneoscleral tissue. In subsequent fluorescence-activated cell sorting (FACS) experiments, we used antibodies against P-cad along with CD90 and CD117 for the enrichment of LEPC, LMSC and LM, respectively. The sorted cells were characterized by immunophenotyping and the repopulation of decellularized limbal scaffolds was evaluated. Our findings demonstrate that P-cad is expressed by epithelial progenitor cells as well as melanocytes in the human limbal epithelial stem cell niche. The modified flow sorting addressing P-cad as well as CD90 and CD117 yielded enriched LEPC (CD90−CD117−P-cad+) and pure populations of LMSC (CD90+CD117−P-cad−) and LM (CD90−CD117+P-cad+). The enriched LEPC showed the expression of epithelial progenitor markers and better colony-forming ability than their P-cad− counterparts. The cultured LEPC and LM exhibited P-cad expression at intercellular junctions and successfully repopulated decellularized limbal scaffolds. These data suggest that P-cad is a critical cell–cell adhesion molecule, connecting LEPC and LM, which may play an important role in the long-term maintenance of LEPC at the limbal stem cell niche; moreover, these findings led to further improvement of cell enrichment protocols to enhance the yield of LEPC.

[1]  U. Schlötzer-Schrehardt,et al.  Efficient Isolation and Functional Characterization of Niche Cells from Human Corneal Limbus , 2022, International journal of molecular sciences.

[2]  U. Schlötzer-Schrehardt,et al.  A Decellularized Human Limbal Scaffold for Limbal Stem Cell Niche Reconstruction , 2021, International journal of molecular sciences.

[3]  U. Schlötzer-Schrehardt,et al.  Melanocytes as emerging key players in niche regulation of limbal epithelial stem cells. , 2021, The ocular surface.

[4]  F. Sefat,et al.  Stem Cell Niche Microenvironment: Review , 2021, Bioengineering.

[5]  M. Lako,et al.  A systematic review of cellular therapies for the treatment of limbal stem cell deficiency affecting one or both eyes. , 2021, The ocular surface.

[6]  U. Schlötzer-Schrehardt,et al.  A decellularized human corneal scaffold for anterior corneal surface reconstruction , 2020, Scientific Reports.

[7]  S. Sel,et al.  Process development and safety evaluation of ABCB5+ limbal stem cells as advanced-therapy medicinal product to treat limbal stem cell deficiency , 2020, Stem cell research & therapy.

[8]  U. Schlötzer-Schrehardt,et al.  Isolation and enrichment of melanocytes from human corneal limbus using CD117 (c-Kit) as selection marker , 2020, Scientific Reports.

[9]  U. Ala,et al.  Whole transcriptome analysis of bovine mammary progenitor cells by P-Cadherin enrichment as a marker in the mammary cell hierarchy , 2020, Scientific Reports.

[10]  L. Schmetterer,et al.  New Technologies in Clinical Trials in Corneal Diseases and Limbal Stem Cell Deficiency: Review from the European Vision Institute Special Interest Focus Group Meeting , 2020, Ophthalmic Research.

[11]  U. Schlötzer-Schrehardt,et al.  Laminin-511-E8 promotes efficient in vitro expansion of human limbal melanocytes , 2020, Scientific Reports.

[12]  R. Horres,et al.  Expression of the COVID‐19 receptor ACE2 in the human conjunctiva , 2020, Journal of medical virology.

[13]  M. Ahearne,et al.  Decellularization and recellularization of cornea: Progress towards a donor alternative. , 2020, Methods.

[14]  M. Stojkovic,et al.  CD200 Expression Marks a Population of Quiescent Limbal Epithelial Stem Cells with Holoclone Forming Ability , 2018, Stem cells.

[15]  C. Gargett,et al.  N-cadherin identifies human endometrial epithelial progenitor cells by in vitro stem cell assays , 2017, Human reproduction.

[16]  N. Koizumi,et al.  Laminin-511 and -521-based matrices for efficient ex vivo-expansion of human limbal epithelial progenitor cells , 2017, Scientific Reports.

[17]  Szu-Yu Chen,et al.  Niche Regulation of Limbal Epithelial Stem Cells: Relationship between Inflammation and Regeneration. , 2016, The ocular surface.

[18]  U. Schlötzer-Schrehardt,et al.  Cell Adhesion Molecules and Stem Cell‐Niche‐Interactions in the Limbal Stem Cell Niche , 2016, Stem cells.

[19]  S. Tuft,et al.  Limbal melanocytes support limbal epithelial stem cells in 2D and 3D microenvironments. , 2015, Experimental eye research.

[20]  F. Carley,et al.  The suitability of corneas stored by organ culture for penetrating keratoplasty and influence of donor and recipient factors on 5-year graft survival. , 2014, Investigative ophthalmology & visual science.

[21]  Simi Ali,et al.  Characterisation of Human Limbal Side Population Cells Isolated Using an Optimised Protocol From an Immortalised Epithelial Cell Line and Primary Limbal Cultures , 2014, Stem Cell Reviews and Reports.

[22]  M. N. Nakatsu,et al.  SSEA4 is a potential negative marker for the enrichment of human corneal epithelial stem/progenitor cells. , 2011, Investigative ophthalmology & visual science.

[23]  M. N. Nakatsu,et al.  SSEA 4 Is a Potential Negative Marker for the Enrichment of Human Corneal Epithelial Stem / Progenitor Cells , 2011 .

[24]  M. Glukhova,et al.  Adhesion within the stem cell niches. , 2009, Current opinion in cell biology.

[25]  K. Tsubota,et al.  N-cadherin in the maintenance of human corneal limbal epithelial progenitor cells in vitro. , 2009, Investigative ophthalmology & visual science.

[26]  S. Grimmond,et al.  Identification of Human Embryonic Stem Cell Surface Markers by Combined Membrane‐Polysome Translation State Array Analysis and Immunotranscriptional Profiling , 2009, Stem cells.

[27]  S. Willaime-Morawek,et al.  E-Cadherin Regulates Neural Stem Cell Self-Renewal , 2009, The Journal of Neuroscience.

[28]  H. Pasolli,et al.  New insights into cadherin function in epidermal sheet formation and maintenance of tissue integrity , 2008, Proceedings of the National Academy of Sciences.

[29]  T. Okano,et al.  Enrichment of corneal epithelial stem/progenitor cells using cell surface markers, integrin alpha6 and CD71. , 2008, Biochemical and biophysical research communications.

[30]  Xi C. He,et al.  N-cadherin expression level distinguishes reserved versus primed states of hematopoietic stem cells. , 2007, Cell stem cell.

[31]  A. Shortt,et al.  Characterization of the Limbal Epithelial Stem Cell Niche: Novel Imaging Techniques Permit In Vivo Observation and Targeted Biopsy of Limbal Epithelial Stem Cells , 2007, Stem cells.

[32]  T. Okano,et al.  N‐Cadherin Is Expressed by Putative Stem/Progenitor Cells and Melanocytes in the Human Limbal Epithelial Stem Cell Niche , 2007, Stem cells.

[33]  D. Wakefield,et al.  The phenotype of limbal epithelial stem cells. , 2007, Investigative ophthalmology & visual science.

[34]  Elaine Fuchs,et al.  Lhx2 Maintains Stem Cell Character in Hair Follicles , 2006, Science.

[35]  U. Schlötzer-Schrehardt,et al.  Identification and characterization of limbal stem cells. , 2005, Experimental eye research.

[36]  Stephen F Badylak,et al.  The extracellular matrix as a scaffold for tissue reconstruction. , 2002, Seminars in cell & developmental biology.

[37]  Kevin Truong,et al.  Cadherins in embryonic and neural morphogenesis , 2000, Nature Reviews Molecular Cell Biology.

[38]  F. Watt,et al.  The Epidermal Stem Cell Compartment: Variation in Expression Levels of E–Cadherin and Catenins Within the Basal Layer of Human Epidermis , 1997, The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society.

[39]  R Kemler,et al.  A role for cadherins in tissue formation. , 1996, Development.

[40]  W. Townsend The limbal palisades of Vogt. , 1991, Transactions of the American Ophthalmological Society.

[41]  T. Sun,et al.  Existence of slow-cycling limbal epithelial basal cells that can be preferentially stimulated to proliferate: Implications on epithelial stem cells , 1989, Cell.

[42]  A. Nose,et al.  A novel cadherin cell adhesion molecule: its expression patterns associated with implantation and organogenesis of mouse embryos , 1986, The Journal of cell biology.