Stem Cells in the Cornea

Abstract

The cornea is the tough, transparent tissue through which light first enters the eye and functions as a barrier to debris and infection as well as two-thirds of the refractive power of the eye. Corneal damage that is not promptly treated will often lead to scarring and vision impairment. Due to the limited options currently available to treat corneal scars, the identification and isolation of stem cells in the cornea has received much attention, as they may have potential for autologous, cell-based approaches to the treatment of damaged corneal tissue.

Niche Regulation of Limbal Epithelial Stem Cells: Relationship between Inflammation and Regeneration

“…(See review. 132 ) A recent study has shown that these limbal stromal progenitors also possess the potential of being reprogrammed into CK3/CK12-expressing (cornea-like) epithelial cells. 133 …”

Mesenchymal Stem Cells Reduce Corneal Fibrosis and Inflammation via Extracellular Vesicle-Mediated Delivery of miRNA

“…MSCs can be isolated from multiple tissues, including adipose tissue and bone marrow. Our previous work has shown that human corneal stroma contains a population of cells (human corneal stem cells, CSSC), which exhibit properties of MSCs and differentiate to corneal keratocytes [2][3][4][5][6][7][8][9]. These cells also block deposition of opaque scar tissue in a corneal wound healing model and elicit regeneration of normal, transparent stromal extracellular matrix [7,8,[10][11][12].…”

“…Our previous work has shown that human corneal stroma contains a population of cells (human corneal stem cells, CSSC), which exhibit properties of MSCs and differentiate to corneal keratocytes [2][3][4][5][6][7][8][9]. These cells also block deposition of opaque scar tissue in a corneal wound healing model and elicit regeneration of normal, transparent stromal extracellular matrix [7,8,[10][11][12]. An important aspect of tissue regeneration effected by MSCs depends on their modification of tissue immune response by secretion of soluble factors to their environment [13][14][15][16].…”

S100A8 and S100A9 proteins are expressed by human corneal stromal dendritic cells

“…This collar of tissue is endowed with specialised functions including (i) maintenance of epithelial mass through the activity of limbal epithelial stem cells, (ii) supplying nutrients and chemical mediators to the avascular cornea through its extensive vascular network1 and (iii) immune surveillance by inflammatory cells 2. The corneal stroma comprises ∼90% of corneal thickness and contains a heterogeneous population of cells, the vast majority of which are resident neural crest-derived keratocytes, and a rarer population of primitive fibrocytes that reside proximal to the limbus and express markers of bone marrow-derived mesenchymal stem cells 3. These cells are responsible for regenerating the corneal stroma under steady state,3 and following pathological insults, they regulate inflammation through their immunosuppressive properties 3.…”

“…The corneal stroma comprises ∼90% of corneal thickness and contains a heterogeneous population of cells, the vast majority of which are resident neural crest-derived keratocytes, and a rarer population of primitive fibrocytes that reside proximal to the limbus and express markers of bone marrow-derived mesenchymal stem cells 3. These cells are responsible for regenerating the corneal stroma under steady state,3 and following pathological insults, they regulate inflammation through their immunosuppressive properties 3. Dendritic cells (DCs) are also resident to the cornea;4 5 these ‘professional’ antigen-presenting cells tend to congregate within the limbal stroma but are also found within the corneal epithelium6 and play a pivotal role in immune surveillance.…”