Expression of a chemokine by ciliary body epithelium in horses with naturally occurring recurrent uveitis and in cultured ciliary body epithelial cells.

The research article evaluates the role of a chemokine protein expressed by ciliary epithelium in uveitis, an inflammation of the eye, in horses. The study showed that horses with uveitis had higher concentrations of this protein and that the protein could contribute to the recruitment and activation of white blood cells.

Research Purpose

• This research aimed to determine the role of a chemokine, RANTES, in uveitis (an inflammation of the eye) in horses. The expression and impact of RANTES protein were assessed in normal horses and those with recurrent uveitis.

Methods

• The researchers involved three groups of horses: normal horses, horses diagnosed with recurrent uveitis, and normal horses of the same age and sex for comparison.
• The hypersensitivity reactions and the chemotactic activity of the recombinant human-regulated upon activation, normal T-cell expressed and secreted (rh-RANTES) protein were examined in horses.
• The researchers used enzyme-linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR) to investigate RANTES expression in the aqueous humor and ciliary body of the eyes of both normal horses and those with uveitis.
• The research also examined the production of RANTES mRNA and protein contents in primary cultures of equine ciliary pigmented epithelial cells, following stimulation with interleukin-1beta and tumor necrosis factor-alpha.

Results

• The study showed strong intradermal hypersensitivity reactions and significant chemotaxis (movement of cells in response to chemical stimuli) of horse leukocytes to rh-RANTES.
• Elevated levels of the rh-RANTES-like protein were observed in the aqueous humor of eyes from horses with uveitis, compared to those from clinically normal horses.
• Horses with uveitis showed RANTES mRNA expression in the ciliary body, while normal horses showed low expression.
• Stimulated ciliary pigmented epithelial cells showed an increase in rh-RANTES-like protein and mRNA expression, compared to unstimulated samples.

Conclusion

• The research concluded that ciliary epithelium could play a role in the recruitment and activation of leukocytes (white blood cells) through the expression of RANTES. This could further clarify the pathogenesis of uveitis and could potentially lead to new therapeutic approaches.