Innate immunity Flashcards
(32 cards)
Give a brief summary of innate immunity
Acts immediately on encounter, consisting of mechanical, chemical and microbiological barriers without longterm memry. Receptors are not unique to a specific cell but are on all of the type
What are antimicrobial proteins/defensins?
Proteins which bind to outer membrane of bacteria resulting in increased membrane permeability
What are the 3 phases of a successful immune response?
Recognition, disposal, communication
WHat are PAMPS and DAMPS
Pathogen associated molecular protiens and damage associated molecular proteins
What 2 receptors are very common?
Toll like receptors and C-type lectins
What system can be activated as a part of the innate immune system?
The Complement system
What are the 3 types of complement system activation?
Classical pathway (antigen antibody complexes, pathogen surfaces) Mannose-binding lectin pathway (binds mannose on pathogen surfaces) and alternate pathway (bacterial cell wall)
What is initially formed as the complement system is initiated?
C3 convertase
What does the C3a/C4a/C5a then do?
Mediates inflammation
What does C3b do?
Opsonisation, binds to complement receptors on phagocytes, marks pathogens to phagocytes
What does C5b, C6, C7, C8, and C9 together form?
Membrane attack complex, lysis of certain pathogens
What do collectins do and name an example
Bind sugars. Mannise binding lectin is an example
What are acute phase proteins?
Proteins released early in response to trauma. Released by liver. Includes CRP
What promotes killinf of internalised microbes of monocytes/macrophages?
Interferon-y from NK cell or Th1 cell
How are internalised microbes killed?
Reactive oxygen intermediates (ROI), or nitric oxide
What are natural killer cells
Cells that recognise via altered self antigens, killing is regulated by perforins and granzymes secreted from lytic vesicles
What do eosinophils target?
Parasitic worms
What do dead/dying neutrophils help make up?
Pus
Are T and B cells really involved with the innate immune system?
No, theyre mostly active immune system. Dont get confused!
How can some vaccines boost the innate immune system?
They can have adjuvants, which activate immune system to ensure the antigen of the vaccine is seen. Antigen presents to T-cells, which help specific B cells to make antibodies.
What do Natural killer cells do?
Kill abnormal cells with “altered self” antigens via perforins and granzymes from lytic vesicles. some produce IFNy.
What chemicals are secreted by phagocytes in tesponse to infection?
Interleukins
What does interleukin 1 do
Activates vascular endothelium and lymphocytes, increases adhesiveness of leukocytes
What does IL6 do
Contributes to acute phase response, introduces B-cell terminal maturation into plasma cells for Ig.
