Mucosa Associated Lymphoid Tissues Flashcards
Where is MALT found?
In the respiratory tract, gastrointestinal tract and genitourinary tract
What is GALT?
Gut-associated lymphoid tissues - part of the overall MALT
What does GALT contain?
Tonsils and adenoids, Peyers patches and appendix
What are adenoids?
They are a type of tonsil (also known as the pharyngeal tonsil) which is located high in the nasopharynx behind the nasal cavity and soft palate
What are the different types of tonsil?
Palatine tonsil, tubal tonsil and lingual tonsil
What are the tonsils and adenoids?
They are similar in structure and function to lymph nodes. They have small ‘wrinkles’ called crypts which subdivide further inside the tonsil
What is the palatine tonsil?
These are the tonsils that most people will think of when talking about tonsils - they are located at the back of the oral cavity on each side
What are the tubal tonsils?
These are located in the nasopharynx near the opening to the inner ear internally
What is the lingual tonsil?
It sits at the base of the tongue
What do the four different tonsils create?
They create a ring around the openings of the nasal and oral cavities. This produces a line of defence against pathogens which may enter into these openings. This is know as the WALDEYERs ring.
What is the Waldeyer’s ring?
The tonsils are collections of lymphatic tissue located around the pharynx. They collectively form a ring arrangement which is known as the Waldeyer’s ring.
What does the Waldeyer’s ring consist of?
Pharyngeal tonsil, tubal tonsils x2, Palatine tonsils x2 and lingual tonsil
What are the tonsils classified as?
MALT, and therefore contain T cells, B cells and macrophages
What are the tonsils role?
They have an important role in fighting infection, the first line of defence against pathogens entering through the nasopharynx.
What happens if the tonsils have an infection?
The antigen from the pathogen will appear on the lymphatics. This may enter the tonsils where it is presented to the cells of the immune system. If an immune cell recognises the antigen it begins to divide rapidly
What does the rapid division in the tonsils cause?
The tonsils to swell
What are some symptoms of tonsillitis?
Sore throat, pain or discomfort when swallowing, fever, swollen glands in the neck
What is the standard treatment for tonsillitis?
Antibiotics
Where are the Peyers patches located?
They are located in the mucosa throughout the small intestine, particular in the ileum
What are the Peyers patches?
They are specialised lymphoid tissue for collecting antigen present in the GI tract
What do the Peyers patches compose of?
They comprise of primary and secondary follicles located immediately beneath specialist epithelium known as follicular-associated epithelium
What is the appendix?
The appendix is part of the large intestine, associated with the caecum and though to have a role in the immune system
What does the appendix have like the tonsils have?
They have crypts and are susceptible to infection
What is there debate about in the appendix?
There is debate whether the appendix plays a role in the immune response, because their appears to be no change in immune response when removed
