Association of levels of antibodies against citrullinated cyclic peptides and citrullinated α-enolase in chronic and aggressive periodontitis as a risk factor of Rheumatoid arthritis: a case control study (Journal of Translational Medicine)

Background: Periodontal disease could be a risk factor for rheumatoid arthritis (RA). It is assumed that the bacterial strain Porphyromonas gingivalis mediates citrullination of host peptides and thereby the generation of RA-associated autoantibodies in genetically predisposed individuals. For that reason non-RA individuals who suffered from generalized aggressive (GAgP, N = 51) and generalized chronic periodontitis (GChP, N = 50) were investigated regarding the occurrence of antibodies against citrullinated cyclic peptides (anti-CCP) and citrullinated α-enolase peptide-1 (anti-CEP-1) in comparison to non-RA non-periodontitis controls (N = 89). Furthermore, putative associations between infections with five periodontopathic bacteria or expression of certain human leucocyte antigens (HLA) to these autoantibodies were investigated. Methods: The presence of anti-CCP and anti-CEP-1 in plasma samples was conducted with enzyme linked immunosorbent assay. Subgingival plaque specimens were taken from the deepest pocket of each quadrant and pooled. For detection of DNA of five periodontopathic bacteria PCR with sequence specific oligonucleotides was carried out. Low resolution HLA typing was carried out with PCR with sequence specific primers. Differences between patients and controls were assessed using Chi square test with Yates correction or Fisher`s exact test if the expected number n in one group was