Objective: To Explore the feasibility of rhesus monkey vascular endothelial cell(RMVEC) transplantation to substitute the allogeneic corneal endothelial cells(CEC), through observe the morphologic and functional change of the vascular endothelial cell which was transplanted to the inner surface of cornea without Descemet's membrane.
Methods: It was an experimental study. The rhesus monkey vascular endothelial cell was cultivated to proliferation and marked by BrdU in vitro. The experimented monkeys are divided into 2 groups: experimental group (6 monkeys), control group (3 monkey). In experimental group: the cultured RMVEC, marked by BrdU, were transplanted onto the posterior surface of rhesus monkey cornea without Descemet's membrane though centrifugal sedimentation, then sew back the corneal graft. In control group: detach the corneal Descemet's Membrane of rhesus monkey but without cultured RMVEC transplantation. Corneal transparency of every monkey was frequently observed postoperation. On 30, 60, 90 postoperative days, corneal graft were respectively detached to observe the distribution, appearance and ultrastructures morphological structure of RMVEC on the inner surface of cornea, by pathological section, anti BrdU monoclonal antibody immunohistochemistry, scanning electronic microscope(SEM) and transmission election microscopy(TEM).
Results: Corneal transparency: In the experimental observation period (three months), the corneal graft of experimental group had better transparency than control group and without corneal neovascularization and bullous keratopathy. Pathological section: A layer of cells with BrdU staining positive was found on the posterior surface of cornea in experimental group, indicated the cells are RMVEC. And no cell-like structure was found in control group. SEM: Experimental group showed that RMVEC with irregular shape uniformly distributed on the inner surface of cornea and growing well, a small amount of white blood cells can be seen between RMVEC, and part of cellular debris exist in the trabecular meshwork. Control group showed a fiber material without RMVEC. TEM: The cultured RMVEC and which in posterior surface of cornea was irregular oblateness, a large number of desmosomes link were been seen between RMVEC. Abundant organelles and characteristic WPBs appear in cytoplasm, which suggest the characteristics and vitality of vascular endothelial cells in vivo, and no cell structure in the control group.
Conclusions: Rhesus monkey endothelial cells can growth on the posterior surface of cornea without Descemet's membrane. The cultured cells, with similar ultrastructure to RMVEC in vivo, can play a role of barrier to keep the corneal dehydration and transparency to some extent.