immune system 2nd line of defense Flashcards
phagocytes
capable of engulfing pathogens, dead/damaged cells, and foreign objects through phagocytosis
neutrophils
engulfs microbes/damaged cells/virus infected cells
monocytes
precursor to macrophages
macrophages
engulfs microbes/debris/virus infected cells and can
release: TNF alpha, IL – 1, IL – 6
TNF alpha
(tumor necrosis factor alpha) increases phagocytic activity, can recognize some types of tumors
IL 1
(Interleukin 1) signals response by white blood cells and distant organs
IL 6
(Interleukin 6) stimulates stem cells to produce more macrophages
natural killer cell
kills abnormal body cells/infected body cells/tumors by inducing apoptosis
interferon
secreted by cells that are infected with viruses that communicate with the cells around it. These cells do this by releasing antiviral proteins that plug up receptors on neighboring cells so viruses can’t bind.
complement
antimicrobial protein that drills holes into foreign cells or coats foreign cells to
make them more susceptible to macrophages. Can trigger/amplify inflammatory response.
what triggers inflammatory response?
an infectious agent or break in barrier
after inflammatory response is triggered…
basophils/damaged cells secrete histamine in the blood and connective tissue
histamine causes…
vasodilation
vasodilation causes…
redness, swelling, heat, and pain due to red and white blood cells leaking out of the vessels near damaged area
what do phagocytes do in inflammatory response?
the ones found in blood engulf pathogens and damaged cells
what does compliment (C’) antimicrobial protein do during inflammatory response?
drills holes into foreign cells, attract more phagocytes and can trigger basophils to release histamine (process cycles until all damaged tissue / pathogens are gone)
what is the purpose of wound healing (clotting)?
seal off affected region and allow repairs to begin
fever in inflammatory response
because some pathogens circulate throughout your blood a systemic response may take place, which includes fever. fever stimulates phagocytes and inhibits microbial growth
materials needed for clotting
(all carried in blood) platelets, the plasma protein fibrinogen, and clotting factors
first step of clotting process
damaged cell and or blood vessels release an enzyme that activates factor X
factor X turns…
turns prothombrin into thrombin
thrombin turns…
fibrinogen into fibrin
fibrin + platelets =
blood clot
why clots are also bad
they circulate through your bloodstream and may cause stroke, heart attack, or thrombosis. body breaks down clots that that form where they aren’t supposed to
how to break a clot
tissue plasminogen activator turns plasminogen into plasmin which breaks the bond between fibrin and platelets
what is included in lymphatic system
vessels, lymph nodes, thymus, tonsils, adenoids, spleen, bone marrow, and possible the appendix
2 functions of lymphatic system
return excess extracellular fluid to the circulatory system (this happens near shoulders) and fight infection
lymph
the fluid of the lymphatic system, enters system through lymphatic capillaries
lymph nodes
concentrated area of ducts that contain lymphocytes (B cells and T cells) and macrophages. during infection these areas become activated and swell = tenderness, pain and aches associated with systemic infections
spleen
stores dormant memory cells
MHC
major histocompatibility complex - how your immune system differentiates between self and nonself. set of glycoproteins (protein/carb combo) on cell membrane. every person has unique MHC except identical twins
MHC class I
found on essentially all nucleated cells except sperm, associated with T cytotoxic cells
MHC class II
found only on antigen presenting cells, associated with T helper cells
