title: Transcutaneous immunization with an outer membrane protein of Porphyromonas gingivalis without adjuvant elicits marked antibody responses.
abstract: OBJECTIVE
  We have previously reported that specific immunoglobulin G (IgG) antibodies induced by transcutaneous immunization (TCI) with a 40-kDa outer membrane protein (40k-OMP) of Porphyromonas gingivalis, with cholera toxin (CT) as adjuvant, inhibited coaggregation by P. gingivalis. In this study, we further pursue the potential of the 40k-OMP as a transcutaneous vaccine.
  
  
  RESULTS
  TCI of rats administered 40k-OMP elicited significant 40k-OMP-specific serum IgG and IgA, as well as salivary IgG antibody titers. Importantly, these antibody responses were induced without adjuvant. Thus, both serum and saliva antibody titers induced by TCI with the 40k-OMP alone were identical to those of 40k-OMP plus cholera toxin as adjuvant. The serum antibody responses induced by 40k-OMP persisted for more than 140 days. On the other hand, salivary IgG anti-40k-OMP antibodies were gradually decreased. Analysis of antibody-forming cells (AFCs) confirmed the antibody titers by detecting high numbers of 40k-OMP-specific IgG AFCs in spleen and cervical lymph node.
  
  
  CONCLUSIONS
  Since 40k-OMP-specific IgG inhibited the coaggregation of P. gingivalis with Streptococcus gordonii, and the hemagglutinin activity of P. gingivalis, TCI with the 40k-OMP may be important as an adjuvant-free immunogen for the prevention of chronic periodontitis.
authors.affiliation: Department of Microbiology and Immunology, Nihon University School of Dentistry at Matsudo, Chiba, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Koizumi
authors.forename: T
authors.initials: T
authors.lastname: Kurita-Ochiai
authors.forename: M
authors.initials: M
authors.lastname: Yamamoto
mesh_terms: D000276:Adjuvants, Immunologic; D000279:Administration, Cutaneous; D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D001422:Bacterial Adhesion / Q000187:drug effects; D001425:Bacterial Outer Membrane Proteins / Q000008:administration & dosage / Q000276:immunology*; D001428:Bacterial Vaccines / Q000008:administration & dosage*; D006384:Hemagglutination / Q000187:drug effects; D007114:Immunization / Q000379:methods*; D007070:Immunoglobulin A / Q000096:biosynthesis / Q000097:blood; D007074:Immunoglobulin G / Q000096:biosynthesis / Q000097:blood; D010518:Periodontitis / Q000517:prevention & control; D016966:Porphyromonas gingivalis / Q000276:immunology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins; D012463:Saliva / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D000907:Antibodies, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001428:Bacterial Vaccines; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D011994:Recombinant Proteins