Tonsils and Immunity
Tonsils are the mucosa-associated lymphoid tissue located in the aerodigestive tract They are the first-line defense against inhaled or ingested pathogens. They are bombarded by numbers of pathogens antigens as compared to other lymphoid tissue which receives pathogen antigen only via the bloodstream.
Tonsils have specialized micropore (M) cells with a tubulovesicular system for antigen transport. At the center of tonsil nodules, there is a germinal center containing densely packed lymphocytes. The antigen-presenting M cells signal the T cells and B cells. B cells produce antibodies mainly IgA which acts as mucosal immune protection. Many of the T cells regulate the antibody response. Other T cells show delayed-type hypersensitivity reaction to large fungi. Another type of T cells can kill virally infected cells. Tonsillar T cell secretes interferon-gamma. Natural killer cells are also present in tonsils.
There are four types of tonsils namely palatine, pharyngeal also known as adenoids, lingual and tubal which form a ring around the oropharynx, and nasopharynx known as the Waldeyer ring of lymphoid tissue.
Tonsils that normally are referred to are palatine. They are present in the pharynx on either side of the throat. When we open our mouth wide, we can see them oval pea-sized lumps behind the throat. They are large in children but they decrease in size in adults.
Tonsils stones happen when debris gets caught in the groove of tonsils. Then white blood cells bout the debris creating a rock-like stone. Usually, these stones can be removed by brushing, water pik, or by the dentist.
In children, the most common problem is inflammation of the tonsils called tonsillitis. This inflammation can be viral or bacterial and treated by throat lozenges, gargling saltwater. Streptococcus bacterial infection commonly affects children which are treated by antibiotics.
Tonsillitis is characterized by
- Hoarseness or loss of voice
- Issues with swallowing
- The white or yellow covering on the tonsils
This infection if reoccurs 4-7 times a year is called recurrent tonsillitis. The treatment for it is tonsillectomy.
Tonsillectomy is a surgical procedure in which the palatine tonsils are removed. Reasons for removal are
- Airway obstruction due to enlarged tonsils
- Sleep apnea
- Recurrent tonsillitis
- The second attack of Quinsy
- Tonsil cancer
- Peritonsillar abscess
Sometimes along with palatine tonsils, adenoids are also removed. Recovery time is from 10 days to 2 weeks.
Tonsillectomy does not appear to affect the long-term immune system of the children. More long studies are yet to be carried out to fully understand the effects of tonsillectomy on the immune system.