Chp 14- Innate Immune System Flashcards
immune system that provides a non-specific type of defense via 1st line of defense (physical) and 2nd line of defense (cellular)
Innate/ Non Specific
physical barrier that serves as body’s border; Why is it difficult for microbes to penetrate this barrier?
Skin; keratin roughness makes breach difficult, releases acid to kill bacteria (sweat)
Innate Immune System is activated when ____?
Microbes penetrate 1st line of defense (physical barriers) , thus activating cellular defenses
process of clearing away debris, dead cells and denatured proteins; Removal of foreign particles/ Microbial infections
phagocytosis
4 Cardinal signs of inflammation
Redness (rubor), Swelling (tumor), Pain (dolor), Heat (calor); sometimes loss of function
results in vasodilation, leakage of fluid from vessels, and migration of leukocytes out of bloodstream
inflammatory process
result of vasodilation/inflammation
More blood supply brings more leukocytes to area
How does innate immune system recognize foreign materials like bacteria?
host’s Toll Like Receptors (TLRs) attach to Pathogen Associated Molecular Patterns; TLRs induce cytokines that regulate intensity/duration of immune response),
4 main phases of Phagocytosis
Chemotaxis, Adherence, Ingestion, Digestion
event of phagocytosis where chemical attraction of the phagocytes to the microorganisms
chemotaxis
event of phagocytosis where the attachment of the phagocyte’s plasma membrane binds to surface of the microbe/foreign material
adherence
Adherence in phagocytosis is facilitated by
attachment of PAMPs of microbe, receptors of TLRs on surface of phagocyte, or mediated by antibodies or complement system (opsonization)
event of phagocytosis where phagocyte extends its psuedopods that engulfs microbe, then plasma membrane fuses to form sac called phagosome
ingestion
event of phagocytosis where phagosome detaches from plasma membrane & enters cytoplasm, combines with lysosome forming phagolysosome
Digestion
Once content of phagolysosome is digested, leftover indigestible material in phagolysosome is called a
residual body
when an infection occurs , ________ immune system is activated … _____ cells like ______ & ______ migrate to the infected area. Migration into the infected tissue stimulates the maturation of ________ into _______.
Innate; phagocytic ; neutrophils & monocytes; monocytes ; macrophages
defensive system of 30 + proteins produced by liver, are not adaptable/do not change & circulate body; complement the immune system; can be activated to help destroy and remove invading microbes.
complement system
Proteins of complement system are Inactive until they are split into
fragements (products)
Proteins of the complement system destroy microbes by
cytolysis, inflammation, and phagocytosis
Classical pathway of complement system requires
antibodies
Classical pathway of complement system
Antibody molecules bind to an antigen (forming an antibody=antigen complex/ immune complex), C1 splits into C2 and C4 , which split into C2a & C2b/ C4a and C4b , C2a and C4b combine and activate into C3 which split into C3a and C3b
Protective Outcomes of Complement System
Opsonization, Inflammation & Cytolysis
immune process that uses opsonins/coating to tag foreign materials for elimination by phagocytosis; enhances phagocytosis via coating of microbes
opsonization
bursting of cell (microbe) due to excess fluid entering
cytolysis
increase of blood vessel permeability and attraction of phagocytes
inflammation
Activation of Complement system leads to
MACs (Membrane Attack Complex’s), Opsonization, Inflammation
