Expression of a chemokine by ciliary body epithelium in horses with naturally occurring recurrent uveitis and in cultured ciliary body epithelial cells.
OBJECTIVE
To determine whether a chemokine (RANTES)-like protein expressed by ciliary epithelium plays a role in uveitis.


METHODS
3 clinically normal horses intradermal, 5 eyes from 5 horses with recurrent uveitis, and 10 normal eyes from 5 age- and sex-matched horses.


METHODS
Cross-reactivity and sensitivity of recombinant human (rh)-regulated upon activation, normal T-cell expressed and secreted (RANTES) protein were evaluated in horses by use of intradermal hypersensitivity reactions and a chemotaxis assay. Aqueous humor and ciliary body of eyes from clinically normal horses and horses with uveitis were examined for RANTES expression by use of an ELISA and reverse transcription-polymerase chain reaction (RT-PCR). Expression of RANTES mRNA and protein content of primary cultures of equine ciliary pigmented epithelial cells (RT-PCR) and culture supernatant (ELISA) were measured 6 or 24 hours, respectively, after cultures were stimulated with interleukin-1beta and tumor necrosis factor-alpha.


RESULTS
Strong reactions to intradermal hypersensitivity testing and significant chemotaxis of equine leukocytes to rh-RANTES wereas observed. Aqueous humor of eyes from horses with uveitis contained increased concentrations of rh-RANTES-like protein (mean +/- SD, 45.9+/-31.7 pg/ml), compared with aqueous humor from clinically normal horses (0 pg/ml). Ciliary body from horses with uveitis expressed RANTES mRNA, whereas ciliary body from clinically normal horses had low mRNA expression. Stimulated ciliary pigmented epithelial cells expressed increased amounts of rh-RANTES-like protein (506.1+/-298.3 pg/ml) and mRNA, compared with unstimulated samples.


CONCLUSIONS
Ciliary epithelium may play a role in recruitment and activation of leukocytes through expression of RANTES.
Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh 27606, USA.
Brian C
BC
Gilger
Ping
P
Yang
Jacklyn H
JH
Salmon
Glenn J
GJ
Jaffe
Janice B
JB
Allen
D000818:Animals; D001082:Aqueous Humor / Q000378:metabolism; D018946:Chemokine CCL5 / Q000096:biosynthesis* / Q000235:genetics; D002633:Chemotaxis; D002924:Ciliary Body / Q000166:cytology / Q000378:metabolism*; D004847:Epithelial Cells / Q000378:metabolism; D005260:Female; D006734:Horse Diseases / Q000378:metabolism*; D006736:Horses; D008297:Male; D012313:RNA / Q000737:chemistry / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D017422:Sequence Analysis, DNA; D014605:Uveitis / Q000378:metabolism / Q000662:veterinary*
D018946:Chemokine CCL5; D012313:RNA