Progenitor Cells in Healing after Pterygium Excision

Abstract

Bone marrow derived progenitor cells were reported to be involved in the pathogenesis of pterygium and have been suggested to be important in angiogenesis and the repair process after tissue damage. In order to investigate the involvement of these cells in wound healing after a pterygium excision, immunohistochemical staining was performed with a temporary amniotic membrane, applied to the bare sclera, after a pterygium excision using various progenitor cell markers, including CD34, c-kit, STRO-1, and AC133, to determine the expression levels of the participating cells. CD34-positive cells were observed along with some round or spindle-shaped mononuclear cells on the stromal side of the amniotic membrane. Some CD34-positive, large, and round or spindle-shaped cells formed clusters resembling small vessels in some regions of the amniotic membrane. c-kit was expressed in the epithelium that had grown over the amniotic membrane and in the spindle-shaped or round mononuclear cells in the stroma. Many stellate- to spindle-shaped fibroblast like cells expressed STRO-1, and AC133 was expressed in some round and ovoid cells. Overall, these results suggest that adult bone marrow-derived progenitor cells, such as endothelial progenitor cells and mesenchymal stem cells, are involved in the wound healing process post-excision in patients with pterygium.

Expression of double strand DNA breaks repair genes in pterygium

“…Some authors confirm such relation, others link the recurrence with reaction to the surgical trauma, 36,37 and with stem and progenitor cells disturbances. 38 These findings are consistent with the data presented here, where in the pterygium tissue no significant differences in the expression of examined genes between primary and recurrent lesions were determined.…”

Immunohistochemical detection of Hsp90 and Ki-67 in pterygium

“…Pterygium is a chronic condition, characterized by the invasion of an altered ocular surface tissue, into the normal cornea [1,29]. …”

“…Many causative environmental factors may induce ocular inflammation, and various types of cytokines may cause abnormal cell changes of the ocular surface. UV-B exposure causes oxidative stress, leading to an excess of many potential mediators of pterygium growth [29]. The noxious effects of UV irradiation are caused either directly by UV phototoxic effects or indirectly by formation of radical oxygen species (ROS).…”

Pterygium: etiology, pathogenesis, treatment

“…формирование мобильного конъюнктивального лоскута либо сверху, либо снизу от ложа птеригиума, которым затем покрывали зону, ранее занимаемую поражением, создавая тем самым барьер из нормальной ткани, предотвращающий повторный рост птеригиума с более периферических участков [39]. Сейчас считается, что свободный конъюнктивальный трансплантат (конъюнктивальная аутотрансплантация) имеет преимущества по сравнению с транспозицией конъюнктивального лоскута, так как первый не только покрывает ложе птеригиума здоровой тканью, но также потенциально обеспечивает лимбальную зону, изначально связанную с птеригиумом, популяцией нормальных стволовых клеток [25,40].…”