Experimental Research On Application Of Cpg Odn Prevention And Treatment Of Allergic Conjunctivitis

Objective To study the effect of topical or systemic CpG ODN treatment on experimental allergic conjunctivitis and related mechanism.Methods OVA-induced allergic conjunctivitis in Balb/c mice were used.Before or after the allergic conjunctivitis induction,CpG ODN or same amount of control GpC ODN were applied topically or intraperitoneally respectively.After the treatment,the mice were pulsed with OVA and examined for clinical symptoms.Mice were then sacrificed for laboratory studies including inflammation cell count in conjunctiva,IgG2a and IgG1 levels in sera,IL-2 level,IL-4 level,CD4+CD25+ and CD80+MHCⅡ+ cells analysis in cultured splenic cells.Results In the examination for preventative function of CpG ODN,compared to GpC·ODN and PBS control groups,both topical and intraperitoneal application with CpG ODN could boost the IgG2a level and lower the IgG1 level in sera.Moreover,these significances keep more days in intraperitoneal treatment than in topical treatment.In the examination for therapeutic function of CpG ODN,compared to GpC ODN and PBS control groups,both topical or intraperitoneal application of CpG ODN manifested lower inflammation cell counts,higher IgG2a production(p＜0.01) in serum,higher IL-2 level, lower IL-4 level in cultured splenocytes supernatant,increased CD4+CD25+ cells percentage and CD80+MHCⅡ+ percentages in cultured splenic cells.However,the differences of clinical scores among each group were not statistically significant(p＞0.05).Conclusion Topical or intraperitoneal CpG ODN treatment might inhibit late-phase reaction of allergic conjunctivitis,possibly by induction of IgG subclass switching and modulation of CD4+CD25+ and CD80+MHCⅡ+ ceils response in treated allergic conjunctivitis mice.But the acute-phase symptom was not affected by topical or systemic CpG ODN administration.