Incorporation of instilled Candida albicans and a lipopolysaccharide into the palatine tonsil of rabbit.

Abstract

The palatine tonsil is thought to be the organ which accepts antigens to initiate an immunological response, but the incorporation of the antigens from the oral cavity was not yet known. To show this incorporation, fluorescence-labeled Candida albicans and a lipopolysaccharide were instilled around the rabbit palatine tonsil. The distribution of fluorescence was examined in frozen sections of the tonsil after 30 , 60 and 180 minutes of the instillation. Candida albicans and a lipopolysaccharide were incorporated into the cryptoepitherial tissue of the palatine tonsil within 30 minutes. The antigens in the epithelium were transported to the intratonsillar follicles and partly to the deep cervical lymph nodes after 60 minutes. The lipopolysaccharide was found intrafollicular by in both the tonsil and the deep cervical lymph nodes earlier than Candida albicans was. Because the normal cryptoepithelium easily passed through the external antigens which were transported to the neighboring lymphoid follicles, it was suggested that the cryptoepithelium was the entrance of the immunological response in the palatine tonsil and neighboring lymphoid tissues in the normal condition.

Simultaneous induction of specific immunoglobulin A–producing cells in major and minor salivary glands after tonsillar application of antigen in rabbits

“…We found that all salivary glands react immunologically as a single unit, rather than showing preferential increases in IgA‐producing cells in palatine glands. Previous studies have shown that other antigens such as bacterial lipopolysaccharides and formalin‐killed yeast cells are rapidly incorporated into palatine tonsils ( 6), where they elicit specific antibodies that appear in the saliva (submitted). The proposed mechanism that tonsils supply IgA‐producing cells to salivary glands is supported by the observations that tonsillectomy results in significant reduction in salivary IgA level in humans ( 3).…”

“…Suspensions at 1×10 10 cells per ml were used in tonsillar application. Every three days, while three rabbits in each experimental group were under general anesthesia induced by ketamine hydrochloride and diethyl ether, 300 μl of sheep red blood cell suspension was dropped on the surface around the openings of the crypts of the palatine tonsils, directly instilled into the stomach using a probe, or intramuscularly injected at both sides of the femoral muscle ( 6). In three control rabbits, 300 μl of phosphate‐buffered saline alone was applied to the surface of the palatine tonsil.…”

“…The crypts that characterize the palatine tonsils can retain antigenic material for long periods, increasing the opportunity for lymphocytes to react with the antigens. Antigens applied around the openings of the crypts are rapidly incorporated into the lymphatic component of the tonsils ( 6). When sheep red blood cells are applied to palatine tonsil of rabbits, a high titer of sheep red blood cell–specific IgA antibody is induced in saliva compared with the titer induced via other routes of immunization ( 5).…”

Sheep Red Blood Cell Instillation at Palatine Tonsil Effectively Induces Specific IgA Class Antibody in Saliva in Rabbits

“…In the tonsil, MC-3 cells have been found at the bottom of its crypt, and have been found to incorporate various kinds of substances into the ton-sillar parenchyma (1,13,14,32). We reported that yeast and bacterial components instilled at the surface of the palatine tonsil were detected in the tonsillar parenchyma within a short time, and were transported to the intra-follicular region of the cervical lymph nodes (8). Based on this prompt incorporation and the similarity to Peyer's patches, we speculated that the palatine tonsil might serve as an inductive site like Peyer's patches in mucosal immunity.…”

Streptococcus sobrinus Antigens That React to Salivary Antibodies Induced by Tonsillar Application of Formalin-Killed S. sobrinus in Rabbits

“…Over the past several years, we have been developing tonsillar application, a new immunization route for mucosal immunity, specifically for the oral cavity (3)(4)(5)(6)(7)13). Tonsillar application of sheep erythrocytes (4) and formalin-killed bacterial cells (7,13) induced production of salivary immunoglobulin A (IgA) and blood plasma IgG more effectively than did intragastric instillation or nasal application.…”