Preliminary characterisation of antigens recognised by monoclonal antibodies raised to Porphyromonas gingivalis and by sera from patients with periodontitis

A panel of 15 monoclonal antibodies (MAbs) was raised to Porphyromonas gingivalis and used to characterise the antigens which they recognise by ELISA. immunofluorescence (IF), Western blotting and patient serum inhibition studies. All the MAbs were specific for P. gingivalis and did not recognise 24 other species. Eight MAbs gave bright ring-like staining patterns against the majority of serotypes of P. gingivalis tested by IF. The antibodies could be grouped into 5 different antigen recognition profiles on Western blotting, and ELISA indicated that 8 of them bound to a capsular extract. Five antibodies bound to antigenic determinants recognised by sera from patients with periodontitis and 4 of these (1A1, 2B/H9, 3B1, 7D5) bound to a P. gingivalis 47kDa protease preparation on Western blotting. These antibodies are potentially useful for the purification and characterisation of biologically active components of P. gingivalis that are recognised by sera from patients with periodontitis.