IM 2 Flashcards
what category is immune responses?
internal defenses
what are the 2 types of immune responses?
innate and adaptive
what’s the encoutner stage?
where pathogen and cell meet
what are locations for encoutner stage?
resident immune cell populations and in circulatin
what is resident immune cell populations?
immune cell in fixed location, pathogen brought by circulation (lymph or blood)
what is circulation for encounter stage?
both pathogen and immune cell in circulation and come together in non-fixed location
what are innate immune responses
general, 2nd line of defense, rapid but limited response
what is the recognition stage?
pathogen and immune cell binding
-general recognition
-toll receptors on immune cell membrane act as pattern-recognition receptors (can recognize large number of patterns)
-resulting binding triggers innate immune responses
what’s innate and adaptive difference?
innate responses contain and limit spread of pathogen while adaptive mounts more specific response
explain the interferon
- cell infected with virus produce proteins called interferons to interfere with viral replication
what is the process of a type 1 interferon
-virus infected cell releases type 1 interferon from cell surface into IF
-most cells have type 1 interferon receptor for binding
-if binding occurs on a non-infected cell, the non-infected cell will start producing antiviral proteins
-if at some point later, the cell becomes virus infected, the antiviral proteins will prevent viral replication
what’s a phagocyte and what are types?
any cell that can do phagocytosis, neutrophils and macrophages
what are neutrophils
quickest response
what are macrophages
have largest capacity
what’s the 4 step process for phagocytosis
- recognition
- ingestion
- digestion
- kill
what are the components of the alternative complement pathway?
complement proteins, opsonization, membrane attack complex
what are complement proteins?
plasma proteins from liver that circulate inactive in blood
-inactive C3 binds pathogen to activate
-activated proteins complement or enhance immune reactions
what is opsonization
portion of active C3 (C3b) left attached to pathogen because the phagocyte has a receptor for C3b and then C3b acts as an opsonin (marker) so that makes recognition easier which enhances phagocytosis
what the membrane attach complex?
- cascade of activations after C3 activates C5-C9
- pore formed by inserting activated C5-C9 into pathogen cell membrane
- inflow of fluid/material into pathogen intracellular environment → apoptosis triggered (programmed cell death)
What are sources of inflammation?
pathogens, abrasions, chemical irritants, cell distortion or disturbance, extreme temperature
what are characteristic symptoms of inflammation?
redness, pain, heat, swelling (also loss of tissue function in damage site sometimes)
what are the goals of inflammation?
-isolate, destroy or inactivate pathogen
-remove debris
-prepare for wound healing and tissue repair
what’s stage 1 of inflammation?
release of inflammatory mediators
types: cytokines, prostaglandins, histamine
what are the local effects for stage 1 inflammation?
-vasodilation microcirculation
-increased permeability of blood vessels
what are the non-local effects for stage 1 inflammation?
-stored immune cells released into circulation, especially from spleen and lymph nodes
-red bone marrow proliferation of new immune cells
what is stage 2 of inflammation?
-phagocyte movement into damage site from blood (start within 1 hour)
-neutrophils early, monocytes mature into wandering macrophages arriving later
what are the steps of stage 2 inflammation?
-margination
-diapedesis
-chemotaxis
what is margination?
phagocytes and local endothelium each form adhesion molecules for attachment to local area
what is diapedesis?
phagocyte migration through blood vessel walls into IF
chemotaxis
phagocyte migration to damage site guided by cytokines using chemoattraction
what is stage 3 of inflammation?
worn out or damaged or dead cells replaced
includes
-angiogenesis
-tissue repair leaving scar
-remodelling after repair
what is the purpose of angiogenesis in inflammation?
a new network of small blood vessels to help remove debris and deliver needed nutrients and oxygen
