Expression of toll-like receptors in the healthy and herpes simplex virus-infected cornea.
OBJECTIVE
To study the expression of toll-like receptors (TLRs) in healthy corneas and corneas with active or nonactive herpetic stromal keratitis (HSK).


METHODS
Eight corneas with HSK (including 5 active and 3 nonactive cases) and 8 healthy corneas were evaluated for TLR1-10 mRNA by reverse transcription-polymerase chain reaction (RT-PCR) and relative real-time PCR. The proteins of TLR2, 9 in 3 different groups, were also compared by immunofluorescence staining. The data were analyzed with SPSS 11.5.


RESULTS
TLR1-10 mRNA was expressed in both healthy and HSK corneas. In the healthy cornea, the mRNA expression of TLR1, 2, 3, 4, and 6 was higher, whereas the expression of TLR7, 8, and 9 was lower relative to TLR 5 and 10. All the TLRs mRNA expression in the active HSK corneas were upregulated, especially TLR4, 7, 8, and 9, compared with the healthy corneas. However, in nonactive HSK corneas, only TLR7 mRNA expression upregulated, whereas the others downregulated. The immunofluorescence staining showed that the expression of TLR 9 was slightly stronger in the cornea with active HSK than that of nonactive and healthy corneas.


CONCLUSIONS
TLRs are expressed diversely in the healthy cornea and could have an important role in innate corneal immunity. TLR4, 8, and 9 may be implicated in the pathogenesis of active HSV infection in the cornea, whereas TLR7 may play a key role in HSK whether it is active or not.
Jin
Xiuming
X
Department of Ophthalmology, Zhejing University School of Medicine, Hangzhou, Zhejiang, China.
Qin
Qin
Q
Chen
Wei
W
Qu
Jia
J
D000328:Adult; D000368:Aged; D003315:Cornea / Q000378:metabolism*; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D005786:Gene Expression Regulation / Q000502:physiology*; D006801:Humans; D016849:Keratitis, Herpetic / Q000235:genetics* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051193:Toll-Like Receptors / Q000235:genetics* / Q000378:metabolism
D012333:RNA, Messenger; D051193:Toll-Like Receptors