Differential recognition of oral indigenous bacteria by salivary immunoglobulins A and G

Microbiol Immunol. 1987;31(3):199-209. doi: 10.1111/j.1348-0421.1987.tb03084.x.


Assuming that salivary immunity to indigenous microorganisms could develop, we assessed antibacterial reactivities of natural salivary antibodies in specific pathogen-free inbred mice. An ELISA was set up, using whole bacterial cells, to map reactivities of salivary IgA and IgG which accounted respectively for 91% and 8.7% of salivary Ig's in the BALB/c mouse. Representative strains of seven species from three genera (Lactobacilli, Staphylococci, and Streptococci), including major and minor components of the murine oral flora (38, 43, and 8%, respectively), were used to determine the presence and level of specific antibodies in individual saliva. It was verified that naturally occurring IgA antibodies can display diverse antibacterial reactivities. A characteristic profile emerged for salivary IgA where antibodies to Streptococcus faecalis predominate. Natural salivary IgG antibodies did not show the same reactivity pattern as IgA, anti-Lactobacilli and anti-Staphylococci reactivities being much less frequent in the salivary IgG repertoire. However, antibodies to S. faecalis occurred at the same high frequency for both isotypes (62-70% of the samples). Besides being species-specific, antibacterial reactivities were also found to be strain-specific. Broad variations in antibacterial titers were detected among individual mice under standardized experimental conditions. Present data thus suggest that the dynamics of salivary antibody production in the mouse reflect a differential natural sensitization of the secretory (IgA) versus the systemic (IgG) immune systems by distinct populations of indigenous bacteria.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacteria / immunology*
  • Enzyme-Linked Immunosorbent Assay
  • Fluorescent Antibody Technique
  • Immunoglobulin A, Secretory / immunology*
  • Immunoglobulin G / immunology*
  • Lactobacillus / immunology
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mouth / microbiology*
  • Saliva / immunology*
  • Specific Pathogen-Free Organisms
  • Staphylococcus / immunology
  • Streptococcus / immunology


  • Immunoglobulin A, Secretory
  • Immunoglobulin G