Effects Of Egg Yolk Immunoglobulin (IgY) Against Porphyromonas Gingivalis On Experimental Periodontitis In Rats

Objective To evaluate the effects of egg yolk immunoglobulin (IgY) against Porphyromonas gingivalis in vitro and reduce the degree of periodontal tissue inflammation in vivo, explore a new immune approach to prevent and cure the chronic periodontitis.Methods The puried anti-Pg IgY was diluted six different concentration (2mg/ml, 1mg/ml, 0.5mg/ml, 0.25mg/ml, 0.125mg/ml, 0.0625mg/ml) and investigated the ihibiton effects of anti-Pg IgY on Pg (ATCC 33277) through discagar diffusion test and dilution test in vitro. Periodontitis was induced by silk ligature technique in male Sprague-Dawley rats, then the rats were fed with 100 g/L high sucrose drinking water and Pg 7 weeks. 15 adult male Sprague-Dawley rats were divided into 5 groups:①Rats with periodontitis treated by anti-Pg IgY (2mg/ml),②Rats with periodontitis treated by minocycline hydrochloride (2mg/ml),③R ats with periodontitis treated by equal volum of PBS,④periodontitis control and⑤the blank control. We recorded the weight of rats, mobility (MOB) of periodontitis, probing depth (PD) and sulcus bleeding index (SBI). After four-week-treatment, the tissues around the test site were excised, samples were embedded and fixed, then the histological assessment were carried out by HE staining to evaluate whether the test sites treated by anti-Pg IgY than before. Then compared the groups treat with anti-Pg IgY and minocycline hydrochloride. Differences between experimental groups were tested with paried t-text, using SPSS 10.0. P values less than 0.05 were considered significant. The animal experiment will evaluate anti-Pg IgY inhibition effects on periodontal tissue inflammation in vivo.Results Compared the OD value, we found the minimal inhibitory concentration of anti-Pg IgY is 0.5mg/ml, and the maxium diameter of bacteriostasis-collares is 15.16±0.33mm. During the vivo study, there were no obvious changes in the weight of rats of any groups and no symptom of toxicity were observed. The periodontitis control rats had bacterial plaque assembled on gingival sulcus inner margin epithelium. Pathology examination also showed a significant gingival epithlium anabrosis and a notable inflammatory cells infiltration. Parts of periodontal membrane spaces became wide, angiectasis and engorge, the alveolar bone was destroyed and absorbed. Anti-Pg IgY and minocycline hydrochloride could significantly improved the periodontal clinical paraments, and there was no significantly difference between them (P>0.05). Anti-Pg IgY and minocycline hydrochloride could lighten the periodontal inflammation, reduced the probing depth and the mobility of test site; However, there are significantly difference between anti-Pg IgY and PBS group (P<0.05). The pathology examination of HE staining also indicated that the test sites which were treated with anti-Pg IgY have a certainly control of gingival inflammation, and the tissue could repaired. These data means anti-Pg IgY could achieve the similar clinic therapeutics with minocycline hydrochloride. Conclusion Our study showed that anti-Pg IgY is kind of effectively immunotherapeutic agent without toxicity, it could effectivly inhibitied Pg in vitro and improved the periodontal tissue inflammation in rats. Anti-Pg IgY have and a bright application foreground in periodontitis immune prophylaxis and treatment.