OBJECTIVETo explore the expression of thrombospondin 2 (TSP2) during the repair process after alkali burn injury to cornea in mice.

METHODSForty mice were employed in the study. The murine corneal alkali burn model was reproduced (n = 35) as experimental group (E), and the mice were randomly divided into control (C, n = 5) and experimental (E, n = 35) groups. The mice in E group were again divided into 7 sub-groups according to different time points [3, 6, 12, 24, 48, 96 and 192 postburn hours (PBHs)] with 5 mice in each sub-group. HE staining, immunocytochemistry (ICC) and RT-PCR were employed to observe the expression of TSP2 in the corneal tissue of mice in both control and all animals in experimental sub-groups at all above mentioned time points (PBHs).

RESULTSTSP2 was expressed in corneal tissue in both C and E groups, especially in the basal layer of epithelial layer, and also a weak expression in substantia propria layer. Compared with that in C group (0.48 +/- 0.15), the expression of TSP2 in E group enhanced at 3 PBH, peaked at 6 PBH, (1.54 +/- 0.45, P < 0.05), dropped to the nadir at 24 PBH (0.73 +/- 0.19), and bounded back afterwards. It peaked again at 96 PBH (1.79 +/- 0.63, P < 0.05), then decreased thereafter, and approached the control level at 192 PBH (P > 0.05). There was remarkable angiogenesis in the cornea at 24 PBH in the mice in E group.

CONCLUSIONThe expressions of TSP2 exhibits fluctuating changes along with the course of repair. This might be related to the compensatory process under stress condition.