Investigation of corneal autoantibodies in horses with immune mediated keratitis (IMMK).

The study investigates the existence of autoantibodies (antibodies that mistakenly attack the body’s own tissues) in horses suffering from immune mediated keratitis (IMMK), suggesting the protein maspin as a potential player, and implying the need for further research to confirm its role in this disease affecting horse’s eyes.

Background and Purpose

• The paper discusses immune mediated keratitis (IMMK), a primary non-ulcerative keratitis disease in horses that leads to sporadic bouts of eye pain and may eventually cause visual impairment. While immunomodulatory treatment typically helps, the root cause of the disease is still unknown. This research primarily looks into the presence of autoantibodies in horses suffering from IMMK.

Methodology

• The study comprises 28 horses with IMMK and 27 healthy control horses. To detect serum autoantibodies against the corneal proteome, methods such as indirect immunofluorescence, one-dimensional (1DE) and two-dimensional electrophoresis (2DE) and subsequent western blot analysis were used.

Results

• Indirect immunofluorescence did not display any notable difference in immune response towards corneal proteins between healthy horses and the ones with IMMK.
• Through western blot analysis, it was found that some horses inflicted by IMMK showed a single band or a single spot not found in the healthy control group.
• The identified spot was detected as maspin (SERPINB5), a protein playing a key role in inhibiting corneal vascularization, cell migration, and cell adhesion to the extracellular matrix.
• However, using a commercially available recombinant human protein did not confirm the blot findings. It was suggested that the human protein might not be fully cross-reactive with the horse protein. Nonetheless, maspin might carry some significance to certain cases of equine IMMK.

Conclusions and Future Work

• Although maspin protein might carry a role in some IMMK instances, the study concluded on an open note, asserting the requirement for additional research in order to elucidate the origin of this disease.