The role of CD4+and CD8+T cells on antibody production by murine Peyer's patch cells following mucosal presentation of Actinomyces viscosus

The effect of immune status, age and genetic background on induction of oral tolerance to Actinomyces viscosus in mice

The aim of the present study was to determine the effect of immune status, age and genetic background on the induction of oral tolerance to Actinomyces viscosus. Suppression of delayed type hypersensitivity (DTH) response and antigen-specific serum antibody levels could be induced in DBA/2 mice intragastrically and systemically immunized with A. viscocus, suggesting the induction of oral tolerance. In contrast, this immune suppression could be abrogated if the animals had been systemically immunized prior to the induction of oral tolerance with the same bacterium. Long-term systemic immunization prior to intragastric immunization with A. viscocus suppressed DTH response only. Cell transfer of this group of animals also suppressed DTH response in the donors, indicating the action of suppressor cells for inhibition of DTH response. Furthermore, oral tolerance to A. viscocus failed to occur in mice aged at 3 days and 1, 2, 4, 6 and 36 weeks old. Mice bearing H-2(d) haplotype were the most susceptible to oral tolerization, followed by H-2(b) and H-2(k). Therefore, the results of the presence study suggest that the induction of oral tolerance to A. viscosus in mice may be dependence on the immune status and genetic background but not age.

The role of the actinomyces in obstructive tonsillar hypertrophy and recurrent tonsillitis in pediatric population

OBJECTIVE

To determine the prevalence of tonsillar Actinomyces in subjects with recurrent tonsillitis and those with obstructive tonsillar hypertrophy, and to determine the association between the presence of Actinomyces and tonsillar volume, and crypt abscess.

SUBJECTS AND METHODS

A prospective designed cross-sectional study consisted of 90 children subjects who underwent tonsillectomy or adenotonsillectomy for recurrent tonsillitis and obstructive tonsillar hypertrophy. The subjects of recurrent tonsillitis (Group A) and obstructive tonsillar hypertrophy (Group B) were compared to the presence of Actinomyces. The relationship between the presence of Actinomyces and the presence of crypt abscess, and tonsillar volume were also compared.

RESULTS

Actinomyces was found to be significantly more prominent in obstructive tonsillar hypertrophy group (61.5%) compared to recurrent tonsillitis group (26.6%) (p<0.001). Additionally, the mean tonsillar volume was significantly higher in tonsils with Actinomyces than those without (p<0.001). The histopathological study revealed that there was no significant inflammatory response to the existence of Actinomyces.

CONCLUSION

According to the presented study, Actinomyces was seen more prominent in subjects with obstructive tonsillar hypertrophy compared those with recurrent tonsillitis. Furthermore Actinomyces had a pathological influence on tonsil size. This study showed there was a significant relation between Actinomyces and enlargement of tonsillar tissue. However, how causes tonsillar hypertrophy is not understood yet in tonsillar disease.