Abstract: Objective: To investigate the inhibiting effect of anti-Hgp44-IgY for experimental periodontitis in rat. Methods: A total of 24 male SD rats were divided randomly into four groups, including the blank group (A), incubation with normal saline (NS) group (B), incubation with anti-Hgp44-IgY group (C) and incubation with cetylpyridinium chloride group (D). Periodontitis was induced by ligation of a silk suture around the neck of the four molar teeth in rats following inoculated with porphyromonas gingivalis. Gingiva index (GI) and BANA test of subgingival bacterial plaque were performed 4 weeks later. Alveolar bone loss (ABL) was detected by dissecting microscope and gum observed by HE stain. The relative mRNA expression levels of IL-10, OPG and RANKL in gums of rats were detected by qRT-PCR and the ratio of OPG/RANKL was calculated. Results: Compared with group B, GI, ABL and BANA were significantly downregulated in both Group C and Group D (P<0.01); while mRNA expression levels of IL-10, OPG and OPG/RANKL ratio were significantly increased in gingival tissue (P<0.01) and the level of RANKL was significantly decreased (P<0.05). The differences of GI, ABL, BANA, IL-10 and RANKL mRNA and OPG/RANKL ratio between Group C and Group D showed no statistical significances; while the OPG mRNA in the Group C was significantly lower than Group D. Conclusion: Anti-Hgp44-IgY can decrease the alveolar bone loss of the experimental periodontitis in rats.

Key words: Experimental periodontitis, Gingipains, Egg yolk antibody, Alveolar bone loss