Experimental Study On The Effect Of Macrophages Activation On Fungal Keratitis Immune Status

Objective: To observe the effect of macrophages activation on immune status ofcorneal, submaxillary lymph nodes and peripheral blood in fungal keratitis.Methods: BALB/c mices were divided into three groups. Firstly A group was amouse model of macrophage activation which was achieved by intra-cornealinstillation of latex beads. Secondly a mouse model of Fusarium solani keratitis wasestablished by epikeratophakia. On day1,3,5,7after inoculation, the appearance ofcorneal ulcer was observed by slitlamp. Infected corneas and submaxillary lymphnodes were subjected to histopathological analysis and immunohistochemistry. Flowcytomytry was used to determine the effects of the fungal keratitis on T-lymphocytesubsets of peripheral blood.Results: After we injected the latex beads into the cornea, we found moremacrophages which were maked by F4/80specific antibody. Keratomycosisdeveloped more severely in the mice treated with Latex Beads than the others on theday5and7after inoculation. In the Latex Beads-treated group, more expression ofinflammatory corpuscle could be detected in the cornea and submaxillary lymphnodes and there was increasing number of T-lymphocytes (CD3+, CD4+andCD8+).The expression of CD4+T-lymphocytes were much more than CD8+T-lymphocytes both in cornea and submaxillary lymph nodes. The level of CD4+T-lymphocytes was declined while the level of CD8+T-lymphocytes was slightlyelevated on the day5and7after inoculation in peripheral blood.Conclusions: Mcrophage activation could be achieved by intra-corneal instillation oflatex beads. Local activation of macrophages may up-regulate the immune responseon cornea and submaxillary lymph nodes and the intense immune response aggravatefungal keratitis. There is reason to believe that systemic immunosuppression may playan important role in the fungal keratitis.