Purpose: To investigate the possible role of stem cell factor (SCF) in the pathogenesis of pterygium.
Methods: The localization of SCF was examined immunohistochemically in excised tissue from 4 primary pterygia and 5 normal conjunctival specimens.
Results: Three of the four pterygia showed strong immunoreactivity of SCF in the subepithelial connective tissue at the cap area. This immunoreactivity was completely blocked by using a primary antibody preincubated with recombinant SCF. The SCF-positive cells were identified as a population of fibroblasts by immunostaining for vimentin and prolyl 4-hydroxylase in adjacent sections. No apparent immunoreactivity of SCF was observed in the subepithelial connective tissues in the head and body of the pterygia and in the normal conjunctiva.
Conclusion: Stem cell factor is overexpressed in fibroblasts at the cap area of most pterygia.