Involvement of bone marrow-derived stem and progenitor cells in the pathogenesis of pterygium.
OBJECTIVE
To evaluate the involvement of multipotential stem and progenitor cells in the pathogenesis of pterygium.


METHODS
Paraffin-embedded and snap-frozen primary pterygium (n = 10) were serially sectioned and analysed immunohistochemically to determine the expression level of AC133 (marker for the primitive haematopoietic progenitors), CD34 (marker for the haematopoietic progenitor cells and endothelium), c-Kit (marker for haematopoietic and stromal progenitor cells), and STRO-1 (a differentiation antigen present on bone marrow fibroblast cells and on various nonhaematopoietic progenitor cells).


RESULTS
In all the primary pterygium, immunoreactivity of AC133 and STRO-1 was found in some of the epithelial and stromal cells, CD34 was observed in the vascular endothelium, and some scattered ovoidal cells were found in the subepithelial connective tissue. C-Kit was expressed mainly in the basal epithelium of the head portions, and some spindle-shaped stromal cells. There is no immunoreactivity of AC133, c-Kit, and STRO-1 in normal conjunctiva, whereas CD34 was mildly stained with vessel wall.


CONCLUSIONS
Multipotential stem and progenitor cells may be involved in the pathogenesis of pterygium through its differentiation into fibroblasts and vascular endothelial cells.
Department of Ophthalmology, Chung-Ang University, Yongsan Hospital, Seoul, Korea.
J
J
Ye
Y S
YS
Song
S H
SH
Kang
K
K
Yao
J C
JC
Kim
D000071916:AC133 Antigen; D036541:ADP-ribosyl Cyclase / Q000378:metabolism; D015703:Antigens, CD / Q000378:metabolism; D018952:Antigens, CD34 / Q000378:metabolism; D015415:Biomarkers / Q000032:analysis; D002454:Cell Differentiation; D058851:GPI-Linked Proteins; D006023:Glycoproteins / Q000378:metabolism; D006412:Hematopoietic Stem Cells / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007124:Immunoenzyme Techniques; D010455:Peptides / Q000378:metabolism; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism; D011625:Pterygium / Q000209:etiology / Q000378:metabolism / Q000473:pathology*
D000071916:AC133 Antigen; D015703:Antigens, CD; D018952:Antigens, CD34; D015415:Biomarkers; D058851:GPI-Linked Proteins; D006023:Glycoproteins; C000606023:PROM1 protein, human; D010455:Peptides; D019009:Proto-Oncogene Proteins c-kit; D036541:ADP-ribosyl Cyclase; C087521:ADP-ribosyl cyclase 2