Expression and significance of CD_(34),AC133,C KIT,STRO 1 in pterygium / 眼科研究

ABSTRACT

Background Many researches have reported the high proliferation ability of pterygium tissue.However,the origin of cells in pterygium tissue and their role in pathogenesis and recurrence of pterygium are below understand up to now.Objective This study is to explore the role of bone marrow derived stem cells and progenitor cells in the pathogenesis of pterygium.Methods Informed consent was obtained from 12 patients with the pterygium stretching the edge of the pupil prior to this trail.Pterygium specimen was obtained from 8 patients with primary pterygium and 4 patients with recurrent pterygium during the operation.The normal conjunctival tissue was obtained from the location of 10 mm from the pterygium in the operation eye.The expression levels of marker of the primitive haematopoietic progenitors(AC133),marker of the haematopoietic progenitor cells and endothelium (CD_(34)),marker of haematopoietic and stromal progenitor cells (C KIT ),and differentiation antigen of bone marrow fibroblast cells and nonhaematopoietic progenitor cells 1 (STRO 1) were detected by using immunohistochemistry.Results Various progenitor cell markers originated from bone marrow,including CD_(34),AC133,C KIT,STRO 1,were positively expressed in pterygium specimen rather than normal conjunctival specimen mainly in the basal epithelium or stroma of pterygia tissue.Majority of the positive cells were seen in the head of pterygium.C KIT positive cells were observed mainly in the basal epithelium and stroma of pterygium.The morphology of positive cells varied upon different distribution.Fibroblast like and spindle shaped positive cells were seen in the stroma layer of pterygium,and round or ovoid shaped cells were in basal epithelial layer.The distribution and shape of positive cells for AC133 and CD_(34) were similar to ones of C KIT but numbers of cells were varied between them.C KIT,AC133 and CD_(34) positive cells were coexpressed in basal epithelium and vascular endothelium.Expression of STRO 1 was found in the stroma layer not in the basal epithelium of pterygium.Similar distribution,numbers and shape of positive cells were seen between recurrent and primary pterygium.Conclusion The cells with stem cells markers and progenitor cells markers originated from bone marrow may play a role in the pathogenesis of pterygium.