Dectin-1 Regulates Macrophage Phenotype Related Factors In Fungal Keratitis Via MAPK Signal Pathway

Purpose: To study macrophage phenotype related factors are regulated by dectin-1 via MAPK singal pathway in Aspergillus fumigates keratitis.Methods: 1.Mouse model of fungal keratitis at 1d,3d and 5d were established by instromal injection.RT-PCR was used to detect the changes in the expression of M1(TNF-ɑ、INOS、IL-6、IL-12)and M2(Arg-1、IL-10)cytokines in macrophages of Aspergillus fumigatus infected mouse corneas at 1,3 and 5 days.2.Mice were injected with dectin-1 agonist Curdlan and inhibitor laminaran 1d post infection,then animal model of mouse Aspergillus fumigatus keratitis was established,The keratitis reaction of mice was observed under slit lamp and the clinical score was recorded,the macrophages were observed under an immunofluorescence microscope;RT-PCR was used to detect the changes in the expression of macrophage M1 and M2 cytokines in the corneas of mice infected with Aspergillus fumigatus after pretreatment with Dectin-1 agonist and inhibitor and the PBS group.3.MAPK pathway inhibitor(P38 JNK ERK inhibitor)pretreated RAW264.7 cells for 2h and stimulated by aspergillus tabaci for 12 h.PCR was used to detect the mRNA expression changes of m1-type cytokines and m2-type cytokines in macrophages.Results: Compared with the normal control group,the mRNA expression levels of macrophage phenotype-related M1 cytokines(TNF-α,INOS,IL-6 and IL-12)and M2 cytokines(Arg-1 and IL-10)were significantly increased after Aspergillus fumigatus infected the cornea of mice at 1d,3d and 5d(P<0.01).2.Compared with the PBS group at three days after fungal infection,the area of corneal ulcer in the dectin-1 agonist Curdlan pretreatment group significantly increased,the inflammatory score increased(p<0.01),and the mRNA level of m1-type cytokines increased in corneal tissue(p<0.01),and the mRNA level of m2-type cytokines decreased(p<0.01).Compared with the PBS group,,the area of corneal ulcer in the dectin-1 inhibitor laminaran pretreatment group was significantly reduced,the inflammation score was decreased(p<0.01),the mRNA level of m1-type cytokines was decreased(p<0.01),and the mRNA level of m2-type cytokines was significantly increased(p<0.01).3.Compared with the control group,RAW264.7 cells in the MAPK pathway inhibitor pretreatment group showed decreased mRNA expression of m1-type cytokines(p<0.01)and increased mRNA expression of m2-type cytokines(p<0.01).Conclusion: In mouse fungal keratitis,dectin-1 can affect the recruitment of mouse corneal macrophages and regulate phenotypic related factors of macrop hages in fungal keratitis through MAPK signaling pathway.