Foundations in Immunology 1-3 Flashcards
Understand the main role of the immune system.
Immune system is body’s ability to resist or eliminate potentially harmful foreign materials (pathogens)
Recognise major cells of the innate immune system and the role they play.
Phagocytes, eosinophils, mast cells, basophils. These cells participate in not only the phagocytosis but also the inflammatory process.
Understand phagocytosis and intracellular killing.
Phagocytosis and intracellular killing are the final steps in the resolution of extracellular microbial infections. Intracellular killing involves oxygen-dependent and oxygen-independent intracellular killing mechanisms.
Understand the basic role of eosinophils and mast cells.
Mast cells are tissue resident cells and uniquely required for immediate hypersensitivity. They play an important role in how the immune system responds to certain bacteria and parasites and they help control other types of immune responses.
Eosinophils are resident to the GI tract, but also home to allergic inflammatory sites. Eosinophilic functions include: movement to inflamed areas, trapping substances, killing cells, anti-parasitic and bactericidal activity, participating in immediate allergic reactions, and modulating inflammatory responses.
Understand the role of cytokines.
Cytokines are small proteins that are crucial in controlling the growth and activity of other immune system cells and blood cells. When released, they signal the immune system to do its job. Cytokines affect the growth of all blood cells and other cells that help the body’s immune and inflammation responses.
Define primary and secondary lymphoid organs.
Primary lymphoid organs: These organs include the bone marrow and the thymus. They make special immune system cells called lymphocytes. Secondary lymphoid organs: These organs include the lymph nodes, the spleen, the tonsils and certain tissue in various mucous membrane layers in the body (for instance, in the bowel).
Define the function of lymphoid organs.
Since the function of the lymphoid organs is to filter and trap invading pathogens and present them to immune competent cells
Understand the features of T-helper 1, T helper 2 and cytotoxic T cells (Tc).
TH1 helper cells release a molecule that activates a type of cell called a macrophage. Macrophages are specialized cells that help eliminate foreign substances from your body.
TH2 helper cells release molecules that activate B cells.
TH1 cells also activate cytotoxic T cells. These are a type of immune cell that can kill certain cells, including foreign cells, cancer cells, and cells infected with a virus.
Understand antigen processing and T-cell interactions.
The usual process of antigen presentation through the MHC I molecule is based on an interaction between the T-cell receptor and a peptide bound to the MHC class I molecule. There is also an interaction between the CD8+ molecule on the surface of the T cell and non-peptide binding regions on the MHC class I molecule.
Understand the role of B cells in immunity.
B cells protect you from infection by making proteins called antibodies. B cells are a type of white blood cell called lymphocytes. When your immune system detects antigens — markers that indicate a threat like a bacteria or virus has entered your body — your B cells produce antibodies to fight the invader.
Understand the structure and function of antibodies.
Antibodies: are proteins that are produced as an immune response against antigens
Antibodies can be divided into two regions:
- Upper region is called antigen binding region, the specific part of the antibody that recognises and interacts with antigen.Different antigens induce the production of different antibodies
- The lower region is called Fc region
Understand the role of the complement.
Complement system consists of more than 30 proteins/factors that are found in the plasms, present in an inactive form. They are activated in a cascade.
The functions incude;
- Direct lysis of target cells
- Enhance the immune response (by increasing blood flow and acr as chemo-attractants and recruit other immune cells to the site of infection)
- Other products facilitate and enhance phagocytosis (opsonization)
Understand the active and passive immunity.
Active immunity:
- Produced by host own immune system
- Takes weeks to develop
- Memory cells produced
- Protection is permanent
Passive immunity:
- Transfer of Abs/cells from other individual
- Immediately has immunity
- No memory cells
- Protection temporary
