Acute inflammation Flashcards
What are the 5 features of acute inflammation?
Calor (heat), Rubor (redness) Tumor (swelling) Dolor (pain) and Functio-laesa (loss of function)
What can cause inflammation? (4)
Infections, tissue necrosis, foreign bodies, immune reactions
What is acute inflammation generally?
The initial rapid response to infection or tissue damage.
Is acute inflammation more closely linked to innate or acquired immunity?
Innate
What two types of patterns stimulate macrophages, dendritic cells or mast cells to produce interleukin 1?
PAMPs or DAMPs.
What does Interleukin 1 do?
Recruits leucocytes (ie neutrophils and monocytes) inducing inflammation
What are the 5 steps of inflammation (5 Rs)
Recognition of the infectious agent
Recruitment of leucocytes
Removal of the agent
Regulation of the agent
Resolution
What are cytokines
Proteins which are secreted by many cell types (including activated lymphocytes, macrophages, dendritic cells) that mediate and regulate immune and inflammatory reactions
What are chemokines
A family of small proteins that act primarily as chemoattractants of specific types of leucocytes.
What is hageman factor? (factor XII)
Inactive pro-inflammatory protein produced by the liver, activated when exposed to sub-endothelial or tissue collagen
What does Hageman factor work to accomplish?
Vasodilation, increased vascular permeability
What are the 3 ways oof activating the complement system?
Classical pathway (Antigen binds to IgG or IgM, activating C1)
Alternative pathway (activation by direct exposure to microbial components)
Mannose-binding lectin pathway (MBL binds to mannose on the bacterial surface)
What do the 3 pathways of the complement system stimulate?
Actication ofC3 convertase which splits C3 into C3a and C3b. C3a recruits and activates leucocytes while C3b binds to the microbe (opsonisation)
C3B can also bind to others of itself to form C5 convertase splitting C5 to form C5a and C5b.
C5b bonds with C6, C7, C8, C9 to form a membrane attack complex causing lysis of the microbe
what do C3a, C4a, and C5a do together?
Cause histamine to be released from mast cells. C5a also acts as a chemotactic aactivation agent for neutrophils, monocytes, eosinophils and basophils.
What activates mast cells
Tissue trauma, C3a and C5a, and cross linkin gof cell surface IgE by antigen.