Immunity and Immunologic Oral Lesions- ash Flashcards
How does the immune response differ from the inflammatory response?
The immune response has the capacity for memory, allowing it to recognize and respond faster to pathogens it has encountered before, while the inflammatory response does not have memory.
What are the key features of innate immunity (natural, native)?
- First line of defense, immediate
- Always present, ready to provide defense against microbes and to eliminate damaged cells
- does NOT memory or antigen specificity
What are the components of innate immunity?
- Epithelium provides mechanical barrier
- Phagocytic cells (neutrophils and macrophages) in the blood that can be recruited
- Dendritic cells in the epithelium, lymphoid organs, and most tissue
- Natural killer cells
- Several plasma proteins
What are the key features of adaptive immunity (acquired, specific)?
- stimulated by microbes and can recognize microbes
- More powerful than innate immunity in fighting infections
- Has MEMORY, leading to increased responsiveness upon re-exposure to the same invader
- Primary white blood cells involved are lymphocytes: T cells, B cells, and natural killer (NK) cells
what are antigens?
An antigen is a foreign substance, such as proteins on microorganisms, that triggers the immune system to defend the body.
What is the goal of the immune system?
The goal is to identify self from non-self to protect the body.
How can transformed human cells become antigenic?
Transformed human cells, such as neoplastic (cancer) cells or virus-infected cells, can become antigenic, triggering an immune response.
What is an autoimmune disease?
It’s when the body’s immune system mistakenly identifies parts of its own body as antigens and attacks them.
What is immunodeficiency?
It’s when the body’s immune system doesn’t recognize certain antigens as foreign, leading to a weak immune response.
What is a hypersensitivity reaction?
It’s when the body overreacts to something it sees as foreign
What is the role of the bone marrow in the immune system?
The bone marrow is a primary lymphoid organ, serving as the birthplace of immune cells and the “factory” for B cells.
What type of cells are found in the bone marrow?
The bone marrow contains pluripotent hematopoietic stem cells, which can differentiate into various types of blood cells, including immune cells.
Where is bone marrow located, and how does it change with age?
Bone marrow is found in the hollow shafts called medullary cavities. As a person ages, red marrow converts to yellow marrow, which contains more fat cells. In adults, red marrow is mainly found in the central skeleton, such as the pelvis, sternum, ribs, and vertebrae.
What is the role of the thymus in the immune system?
The thymus is a primary lymphoid organ and serves as the “T-cell factory.” Lymphocytes migrate here from the bone marrow to mature into T cells.
What is the role of the spleen in the immune system?
The spleen is a secondary lymphoid organ that acts as a filter for the circulatory system and responds to antigens in the blood.
What is the largest lymphatic organ in the body?
spleen
What is the function of the spleen in terms of filtering and lymphocytes?
The spleen is a filtering organ that filters the blood and contains 25% of the body’s mature lymphocytes.
How do lymph nodes and the spleen differ in terms of their response to influences?
Lymph nodes respond primarily to regional influences, while the spleen responds to systemic influences.
How long do T cells and B cells take to travel through the body?
The transit time for T cells is about 5-6 hours, while B cells take longer to travel.
What are the main components of the spleen?
The spleen is encapsulated and contains two main parts:
- White pulp, which contains lymphoid cells and is involved in immune responses.
- Red pulp, which is the blood-filtering system that removes old or damaged blood cells.
What is the role of lymph nodes in the immune system?
Lymph nodes are secondary lymphoid organs that act as mini regional filters in the lymphatic system, filtering lymph and responding to local infections or antigens.
What does Mucosal-Associated Lymphoid Tissue (MALT) consist of?
MALT consists of non-encapsulated clusters of lymphatic tissue found in various submucosal sites throughout the body. It is populated by lymphocytes, plasma cells, and macrophages, which are ready to encounter antigens trying to pass through mucosal surfaces
Where is Mucosal-Associated Lymphoid Tissue (MALT) found?
MALT is found at the gateways to the body, including:
- Waldyer’s ring in the oropharynx
- Peyer’s patches in the small intestines
- Gut-associated lymphoid tissue (GALT) along the gastrointestinal tract.
Where do T-cell lymphocytes develop, mature, and reside?
T-cell lymphocytes develop in the bone marrow, mature in the thymus, and reside in lymphoid tissue and blood.