Immunity Flashcards
What are the two types of barrier immunity?
Physical - skin, mucus, respiratory cilia, commensal organisms
Biochemical - antimicrobial effect - sebaceous secretions in skin, lysozyme in tears, spermine in sperm, gastric acidity
Define what is an antigen
Any substance capable of inducing a specific immune response
What are the differences between innate & adaptive immunity?
Innate - primary line of defence, immediate response, recognise certain threats, no antigen presentation, no clonal selection, no immunological memory
Adaptive - secondary line of defence, delayed response, recognise all threats, antigen presentation, clonal selection, immunological memory
What is the main function of neutrophils?
Phagocytosis (mainly innate)
What are the types of T lymphyocytes?
Cytotoxic, memory, helper, suppressor
What are the types of B lymphocytes?
Plasma cells, memory cells
What is the difference between monocytes & macrophages?
Monocytes are when they’re in the blood.
Become macrophages when in tissue.
What is the function of monocytes/macrophages?
Phagocytosis –> adaptive antigen presenting cells
What are eosinophils for?
Parasitic infections & allergic responses
What are basophils & mast cells for?
Inflammatory & hypersensitivity
What is involved in innate cell-mediated immunity?
Phagocytes -
- Polymorphonuclear leukocytes - Neutrophils
- Mononuclear phagocyte system - monocytes/macrophages
What is neutropenia?
Low neutrophil level in blood
What is the oxidative burst in phagocytosis?
The process of creating the toxic chemicals used to digest the ingested microbe
What is the role of natural killer cells in innate cell-mediated immunity?
Detects when cells lose MHC class I surface molecules → NK cell activation → inserts pore-forming molecules into target cell to pumps cytotoxic chemicals in
What is involved in innate humoral immunity?
- Acute phase proteins (APPs) - released in inflammation/tissue injury for immediate/non-specific cytoxicity.
E.g. CRP, pro-calcitonin, alkaline phosphatase, ferritin - Complement - Alternative and classical pathways
Alternative - antibody independent cell lysis
Classical - antibody dependent cell lysis