Protein survey in periodontal pockets using proteome analysis.

Aim: To reveal proteins associated with periodontal disease in sites where periodontopathogenic bacteria were not detectable comparing the proteomic profile of interproximal pocket tissues with interproximal healthy tissues in the same subject Methods: 39 patients, with moderate to advanced chronic periodontitis and presenting with at least one intrabony defect next to a healthy interproximal site were enrolled. The periodontal defects were treated with osseous resective surgery, and the flap design included both the periodontal pockets and the neighboring interproximal healthy sites. Pocket-associated and healthy tissues were harvested for proteomic analyses. The results were processed using standard proteomic and statistical analyses to size and density of the spots. Results: 15 proteins resulted differently expressed between pathological and healthy tissues. Particularly, annexin A2, actin cytoplasmic 1, carbonic anhydrase 1 & 2; Ig kappa chain C region (2 spots) and flavinreductase were overexpressed, whereas 14-3-3 protein sigma and zeta/delta, heat shock protein beta -1 (2 spots), triosophosphateisomerase, peroxiredoxin-1, fatty acid-binding protein-epidermal, and galectin-7 were underexpressed in pathological tissue. Conclusions: The unbalanced functional network of proteins involved could hinder adequate tissue response to pathogenic noxa through different mechanisms, ranging from a lack of control of cellular stresses to an alteration of immune and apoptotic capacity. In particular it seems that it is more significant deficiency more than the over-expression of proteins to justify the pathodynamic of the periodontal disease. The study of periodontal pocket tissue proteomic profile would be crucial to better understand the pathogenesis of and the therapeutic strategies for periodontitis.