Effect of Multiple Antigenic Exposures in the Gut on Oral Tolerance and Induction of Antibacterial Systemic Immunity
AUTOR(ES)
Garg, Sanjay
FONTE
American Society for Microbiology
RESUMO
We have analyzed oral tolerance of microbial antigens in an experimental model in which mice are treated orally with a single small dose of soluble antigen and challenged systemically with the antigen in complete Freund's adjuvant. We found that, while oral administration of sonicated extracts of either Leishmania major, Leishmania donovani, or Staphylococcus aureus was tolerogenic, as was administration of the nominal antigen ovalbumin or conalbumin, oral administration of Escherichia coli or Salmonella typhimurium sonicated extract was not. Since E. coli is an enteric commensal that colonizes the intestine soon after birth, these data suggested that lack of demonstrable oral tolerance may be related to the frequency of oral exposure to an antigen. In support of this, we found that multiple oral doses of ovalbumin or S. aureus or L. donovani antigens did not increase systemic hyporesponsiveness beyond that achieved with a single oral dose. We have also tested the ability of mice fed with sonicates of the tolerogenic S. aureus or the nontolerogenic S. typhimurium to clear a subsequent systemic infection with the homologous bacteria and found that, while clearance of S. aureus was unaffected by prior feeding, clearance of S. typhimurium was actually enhanced. The data suggest that frequent oral antigenic exposure may eventually lead to induction of systemic immunity in tolerant mice.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=96974Documentos Relacionados
- Effect of oral immunization with Pseudomonas aeruginosa on the development of specific antibacterial immunity in the lungs.
- Induction of oral tolerance and the effect of interleukin-4 on murine skin allograft rejection
- Induction of immunity and oral tolerance with polymorphic class II major histocompatibility complex allopeptides in the rat.
- Effect of Probiotic Bacteria on Induction and Maintenance of Oral Tolerance to β-Lactoglobulin in Gnotobiotic Mice
- Effect of iron on antibacterial immunity in vaccinated mice.