Expressions of TLR4 and Dectin-1 in cornea tissue of rats with Aspergillus fungal keratitis and their effects in pathogenesis of keratitis / 吉林大学学报(医学版)

ABSTRACT

Objective To explore the expressions of Dectin-1 and Toll-like receptor 4 (TLR4)and the secretory charateristics of inflammatory factors of the Aspergillus fumigatus infected cornea of the rats,and to clarify theirs role in the pathogenesis of rat keratitis.Methods 40 SD rats were separated into control group (n = 10)and aspergillus keratitis group (n=30).The rats in aspergillus keratitis group were infected by Aspergillus fumigatus in two eyes for 12,24 and 48 h,and the cornea tissue was took and ELISA kit was used to detect the level of inflammatory cytokines IL-1,TNF-a,IL- 6,IL-10,and NF-κB;immunohistochemistry,Western blotting and RT-PCR methods were used to determine the Dectin-1 and TLR4 protein and mRNA expressions.Results The rat models were successfully established.The eyes of the rats in control group were limpid tested by corneal slit lamp, however,there existed a clear boundary film on the surface of eyes of the rats in aspergillus keratitis group infected for 12 h,white infiltrates and bloodshot in the eyes in 24 h group and the white infiltrates were further strengthened and almost covered the entire eyes in 48 h group. The order of inflammatory cytokines IL-1,TNF-α,IL-6,IL-10, NF-κB was48 h group> 24 h group> 12 h group> control group (P < 0.05),so did the expression levels of Dectin-1 and TLR4 protein and mRNA in various groups tested by Western blotting and RT-PCR methods.The expression levels of Dectin-1 and TLR4 were increased with the prolongation of time investigated by immunohistochemical staining.Conclusion Dectin-1 and TLR4 are secreted in excess after the eyes are infected with fumigatus,which promotes the expressions of related inflammatory cytokines and results in the occurrence of keratitis.