[A primary study on soluble protein and soluble antigen of corneal stroma in Mooren ' s ulcer patients]

To investigate changes of soluble protein and soluble antigen of corneal stroma in Mooren's ulcer patients and autoantibody in the patients' sera against the soluble antigen.

The corneal stromal specimens taken from 15 Mooren's ulcer patients who received lamellar keratoplasty were studied. Soluble protein and soluble antigen of the corneal stroma were extracted. The soluble protein contents were measured. The soluble corneal stromal extracts were tested by using sodium dodecyl sulfate polyacrylamide gel electrophoresis technique (SDS-PAGE). The protein strips of electrophoresis were analyzed using thin layer scanning system. Peripheral vein blood of 15 patients with Mooren's ulcer was taken. Indirect enzyme linked immunosorbent assay (ELISA) was used to test the level of autoantibody in the patients' sera against the soluble antigen of the corneal stroma.

Soluble protein contents of corneal stroma extracts were 0.435 mg/L in the patient group and 0.645 mg/L in the normal control group. SDS-PAGE results of the affected corneal stromal extracts showed that a protein about 12 000 of molecular weight appeared at 0.92 of Rf. 12 000 protein was not found in the control group. The content of 12 000 protein was 22.1% of the total soluble protein of the involved corneal stroma. The level of autoantibody in the patients' sera against the soluble antigen was much higher than that of normal control (t = 15.15,P < 0.001).

The appearance of 12 000 protein in the soluble protein of the involved corneal stroma may have a connection with the soluble corneal stromal antigen. The level of the autoantibody in the patients' sera against the soluble antigen is significantly higher than that of the control. It represents that Mooren's ulcer patients have an autoimmune reaction to the corneal stroma.