Ischemic tissue injury and progenitor cell tropism: significant contributors to the pathogenesis of pterygium
Kyoung Woo Kim1, Hyo Shin Ha2 and Jae Chan Kim1
1Department of Ophthalmology, Chung-Ang University Hospital, College of Medicine, Seoul, Korea and 2Department of Ophthalmology, Seoul Paik Hospital, University of Inje College of Medicine, Seoul, Korea
Offprint requests to: Prof. Jae Chan Kim, Department of Ophtalmology, Chung-Ang University Hospital, 102 Heukseok-ro, Dongjak-gu, Seoul 156-755, Korea. e-mail: jck50ey@kornet.net or jck50ey@daum.net
Summary. Pterygium is a common ocular surface disease characterized by triangular wing-like growth consisting of subconjunctival hypertrophic connective tissue. Pterygium is easily complicated by adhesion to the eyelid and diplopia related to motility restriction of the eyeball. Beyond the cosmetic problems, this condition has a catastrophic effect on quality of life. Post-surgical recurrence rates of pterygium excision have been reported to be very high. Therefore, identifying the distinct pathogenic pathways of the disease may lead to new therapeutic strategies with lower risk of treatment failure. Based on the relatively low vascularity and known-predominance of disease occurrence in the nasal conjunctiva of normal eyes, we proposed that hypoxic ischemic injury can elicit the development of pterygium. Here, we review hypoxia-inducible factor (HIF)-1alpha-induced activation of the stromal cell-derived factor-1 (SDF-1)/chemokine receptor type 4 (CXCR4) signaling pathway as a possible mechanism. Supporting this concept of pathogenic mechanism, we also highlight bone marrow-derived progenitor cell tropism as a main contributor to pterygium pathogenesis. Histol Histopathol 30, 311-320 (2015)
Key words: Pterygium, Hypoxia, HIF-1alpha, SDF-1, CXCR4, Progenitor cell
DOI: 10.14670/HH-30.311