[Occurrence of various immunoglobulin isotopes in horses with equine recurrent uveitis (ERU)].

This research investigated immunoglobulin levels in the eyes of horses with equine recurrent uveitis (ERU), compared to healthy horses. The study found that horses with ERU have significantly higher levels of all types of immunoglobulins measured in their eye fluid, suggesting possible local production of antibodies or increased permeability of intraocular barriers in affected horses.

Participant Selection

In the research, the eyes of 57 horses were investigated. This included 30 healthy eyes and 41 eyes affected by equine recurrent uveitis (ERU).

Procedure and Techniques

Total immunoglobulin titers and titers of specific immunoglobulins (IgGa, IgGb, IgM) were measured in the aqueous humour, vitreous, and serum of the horses. This was achieved using a variety of enzyme-linked immunosorbent assay (ELISA) techniques.

Findings

• All samples investigated contained detectable amounts of immunoglobulins, regardless of health status.
• Significantly increased titers of all immunoglobulin types studied were found in the aqueous humour and vitreous fluid of ERU-affected eyes, as compared to the control (healthy) eyes.
• In the case of IgM, while it was detected in only 2 out of 30 aqueous humour samples and none of the vitreous samples of healthy eyes, around 80% samples of ERU eyes revealed considerable IgM levels.
• The ratio of IgGa to IgGb differed in the eye compared to the serum, more frequently in ERU-affected eyes than in healthy ones.
• No significant differences were found in the serum immunoglobulin levels of healthy horses as opposed to those affected by ERU, suggesting the differences observed were specific to ocular tissues.

Conclusions

Overall, the results point to a physiological appearance of immunoglobulins in a healthy eye. The heightened levels of immunoglobulins in the eyes affected by ERU could either be caused by local production of antibodies in response to inflammation or an increased permeability of the barriers in the eye, allowing more immunoglobulins to penetrate. Further research is needed to elucidate the exact mechanism and the potential therapeutic implications.