IADR Abstract Archives
A. actinomycetemcomitans Omp29 binding to extracellular matrix proteins
Objectives: The ability of A. actinomycetemcomitans (Aa) to interact with host molecules is a critical event in the colonization of host tissues. Omp29 is one of the major outer membrane proteins of Aa and it is associated with invasion of gingival epithelial cells, but the interaction between AaOMP29 to host molecules is still unknown. We aimed to test the hypothesis that AaOmp29 interacts with extracellular matrix proteins (pECM).
Methods: Aaomp29 was cloned in an expression vector, and recombinant Omp29His was obtained. Binding of Omp29His to laminin, plasminogen, fibrinogen, collagens types I and IV, cellular fibronectin, plasma fibronectin, and to negative control, fetuin, was determined by an ELISA-based assay. Differences in binding to each pECM and the negative control were assessed by Student’s two-tailed t test, in triplicate in three independent assays.
Results: AaOmp29 seems to have a specific binding to fibronectin since OD490nm for cellular and plasmatic fibronectins assays were 2.26±0.42 and 2.19±0.52, respectively, when compared to fetuin (1.68±0.09), whereas OD values for laminin (2.0±0.54), plasminogen (1.83±0.62), fibrinogen (1.74±0.51), collagens type I (1.66±0.2) and IV (1.3±0.31) did not differ from negative control. Omp29His was able to interact with plasmatic and cellular fibronectin (p<0.05), but not with collagens, fibrinogen, laminin and plasminogen.
Conclusions: Binding of Omp29 to pECM may be an important mechanism by which Aa interacts with the host cells on the pathogenesis of periodontitis and related systemic diseases.
Methods: Aaomp29 was cloned in an expression vector, and recombinant Omp29His was obtained. Binding of Omp29His to laminin, plasminogen, fibrinogen, collagens types I and IV, cellular fibronectin, plasma fibronectin, and to negative control, fetuin, was determined by an ELISA-based assay. Differences in binding to each pECM and the negative control were assessed by Student’s two-tailed t test, in triplicate in three independent assays.
Results: AaOmp29 seems to have a specific binding to fibronectin since OD490nm for cellular and plasmatic fibronectins assays were 2.26±0.42 and 2.19±0.52, respectively, when compared to fetuin (1.68±0.09), whereas OD values for laminin (2.0±0.54), plasminogen (1.83±0.62), fibrinogen (1.74±0.51), collagens type I (1.66±0.2) and IV (1.3±0.31) did not differ from negative control. Omp29His was able to interact with plasmatic and cellular fibronectin (p<0.05), but not with collagens, fibrinogen, laminin and plasminogen.
Conclusions: Binding of Omp29 to pECM may be an important mechanism by which Aa interacts with the host cells on the pathogenesis of periodontitis and related systemic diseases.