Innate + Adaptive Immunity Flashcards
What are the (4) roles of the immune system?
- Immunity to infection
- Inflammatory processes
- Removal of senescent cells
- Defence against neoplasia e.g. cancer
What is the medical relevance of Immunology?
Immune disorders
Immunology tests
Immunotherapies
Immunoprophylaxis
What general immune disorders are there?
Immunodeficiency - primary (birth) + secondary (later in life)
Hypersensitivity (allergy, anaphylaxis)
Autoimmunity - failure to distinguish self from non-self
What general immunology tests are available?
- Serology - antibody detection after infection
- Cellular response to infection e.g. tuberculin skin test, interferon gamma release assay)
- Diagnosis of hypersensitivity + AI
- Cross matching + tissue typing
What general immunotherapies are available?
- Immunodeficiency - transfusion of ABs from extracted blood
- Hypersensitivity - de sensitisation via slow gradual exposure
- Anti TNF drugs for autoimmunity
- Infection (IFN for chronic HCV infection)
- Cancer e.g. IL-2 for melanoma + renal cancer
- Transplantation
What method(s) of immunoprophylaxis exist?
Vaccination against infections + some cancers
Define the term ‘Antigen’
Any substance capable of inducing a specific immune response i.e. targets of immune system
What are ‘self-antigens’?
Molecules usually tolerated/ignored by own immune system
What can differentiate antigens from host molecules?
Pathogen-associated molecular patterns (PAMPs)
What components can the immune system be divided into?
Innate + Adaptive
Antigens with PAMPs mostly targeted by innate mechanisms, other antigens targeted by adaptive
List the components/differences of innate + adaptive immune system
Innate:
- primary line of defence
- immediate response
- no clonal selection (same response every time)
- no immunological memory
- no antigen presentation
- recognises certain threats
- complement
- first point of innate epithelial barriers
- natural killer cells for if antigens are inside cells e.g. virus
Adaptive:
- secondary line of defence
- delayed response
- recognises all threats
- antigen presentation
- clonal selection (clones of cells that best tackled Ags)
- immunological memory (quicker, specific response in future)
- only 1 receptor on each B lymphocyte specific for Ag
Which immune cells are involved in innate immunity?
Epithelial barriers Neutrophils, eosinophils, basophils (Phagocytes) Dendritic cells NK cells Complement
Which immune cells are involved in adaptive immunity?
B lymphocytes - plasma + memory cells T lymphocytes - cytotoxic, memory, helper, suppressor Antibodies Effector T cells Monocytes + Macrophages (phagocytes)
What is the difference between monocytes and macrophages?
No difference! Same cell just different name depending on where they appear. Monocytes = within cells, Macrophages = outside cells
What role do eosinophils have?
Associated with parasitic infections + allergic responses - filled with granules that release histamine + other mediators
What role do basophils and mast cells have?
Inflammatory + hypersensitivity responses
What are mucosa associated lymphoid tissue?
MALT = adenoids + tonsils
What is the role of the thymus?
Site for T lymphocyte maturation before birth