Abstract
Abstract: :
Purpose: To compare the difference in proliferative capacity between human corneal endothelial cells (HCEC) cultured from the central area of the cornea (0–6.75mm) and those from the peripheral area (6.75–9.5mm). Methods: Human corneas from two groups of donors (young group: <30 years of age, and old group: > 50 years of age) were obtained and Descemet’s membrane with HCEC from the central area (0–6.75mm) and the peripheral area (6.75–9.5mm) were stripped from these corneas. HCEC were isolated from Descemet’s membranes and cultivated. The rest of the peripheral and limbal area of the cornea was fixed and stained with H&E. to elucidate contamination with the trabecular meshwork tissue. Cell morphology was documented by inverted phase–contrast microscopy. Equal numbers of passage 2 endothelial cells from each area were seeded and cell numbers were determined by hemacytometer at various times after seeding. Doubling times of cells from each area were compared. Antibody against MCM2 tested for competence to replicate. Results: Morphologically, HCEC from the central area were similar to cells from the peripheral area. The doubling time (hours) of HCEC from the central area was 28.02±10.59 in the young group (n=5) and 47.49±11.42 in the old group (n=5) and from the peripheral area, 27.57±9.65 in the young group and 36.51±7.59 in the old group. There was no statistical difference between the central areas and peripheral area in each age group. A statistical difference in doubling time was only seen between younger group and older group (p<0.05). MCM2 positive cells from central areas were seen as well as cells from peripheral areas. There was no statistical difference of positive rates between these two areas in each group. Conclusions: HCEC from both areas could proliferate in vitro in response to growth promoting agents. The morphology and proliferation rate of HCEC from the central area were similar to those from the peripheral area. These results indicate that corneal endothelium from the central area still has potential proliferative capacity. Further investigation will be needed to observe the existence of highly proliferative "stem like" cells in the far–peripheral area.
Keywords: cornea: endothelium