Secretory abzyme IgA, enzymes and DNA of oral fluid in chronic periodontitis

Catalytic abzyme activity of IgA and corresponding enzymes of oral fluid in patients with chronic periodontitis was studied. The individuals with healthy state of oral cavity were used as controls. Various kinds of proteolytic, oxidoreductase, and DNase activity were investigated; the concentarion of oral fluid DNA was evaluated as well. IgA fractions were isolated from the oral fluids by affinity chromatography on a matrix with polyclonal antibodies against human IgA, Elastase, proteolytic, cathepsin-like and amidase activities were investigated by colorimetric methods. DNase activity was assessed by the rivanol clot test. DNA concentrations in the oral fluid were determined by fluorimetric DNA test with PicoGreen fluorochrome. It has been established that certain kinds of IgA abzyme activities and oral fluid enzymes become substantially elevated following the exacerbations of chronic periodontitis in comparison with healthy controls (p<0.01-0.001). It refers to elastase, peroxidase, cathepsin, and catalase activity of oral cavity. The progression of chronic periodontitis is also characterized by high levels of patients’ DNA contents in oral fluid (p<0.001). For the diagnosis of chronic periodontitis the ROC-analysis of examined laboratory markers found the maximum diagnostic value of oral elastase testing (specificity of the test – 0,97; sensitivity – 0,85).