immuno- L3: complement system and inflammation

adaptive

is inflammation in relation to innate or adaptive immunity?

an influx of WBCs and fluid to fight infection and aid tissue repair

what happens during acute inflammation?

chronic inflammation, which leads to tissue damage and loss of tissue function

what happens if the inducer of inflammation is not removed?

if the inducer of inflammation is not removed

why does chronic inflammation occur?

neutrophils

when bacteria enters, what is the first cell to arrive?

dendritic cells and macrophages

after the influx of neutrophils to the site of invasion, what cells arrive next?

neutrophils

which are arrive quicker to the site of invasion- macrophages or neutrophils?

macrophages

which are more efficient at producing immune responses- macrophages or neutrophils?

cytokines, chemokines, lipid mediators

what are the inflammatory regulators?

phagocytizing the invadors

when macrophages are activated innately, they respond by...

phagocytizing the invadors and then displaying the MHC II and producing enzymes

when macrophages are activated by an adaptive immune response, they respond by...

both

if innate, they just phagocytize the invador and are done

if adaptive, they phagocytize the invador and then act as APCs

are macrophages activated innately or adaptively?

TNF

IL-1

IL-6

macrophages and dendritic cells secrete pro-inflammatory cytokines, especially what types?

signal endothelial cells to make them leaky to fluid (so plasma with antibodies and complement can be secreted) and sticky for leukocytes

what do TNF and IL-1 do?

produce inflammation symptoms- heat, swelling, pain, redness

act on neutrophils to enhance their ability to kill microbes

what are the effects of TNF?

TNF

what is the main cytokine for producing symptoms of inflammation?

macrophages, dendritic cells

what cell secretes the cytokine TNF?

activate lymphocytes for adaptive immunity

send signals to the brain and liver

what are the main effects of IL-1?

IL-1

which is the main cytokine for activating lymphocytes?

mediates septic shock

promotes adaptive immune response

has C reactive protein

what are the main effects of IL-6?

CRP- C reactive protein

what is the protein thats levels are measured to indicate systemic inflammation?

IL-6

which cytokine has CRP- C reactive protein?

IL-6

which cytokine produces a systemic response?

the secretion of cytokines (TNF, IL-1) by macrophages and dendritic cells

what triggers neutrophils to begin their response?

short

are neutrophils short or long lived?

they often damage host tissue as a by-product of their response

what is a problem that neutrophils cause?

chemotaxis- chemical signals

how do neutrophils find the site of infection?

the type of chemokines

the type of cell that responds to an invasion depends on what?

Kupffer cells (macrophages of the liver)

in dogs, bacterial clearance is mostly done by....

pulmonary macrophages

in cats, bacterial clearance is mostly done by....

loss of appetite

fever

depression

neutrophilia

what are the symptoms of systematic inflammation?

CRP and opsonin

what are the main proteins that play a role in the acute phase of systemic inflammation?

systemic inflammatory response syndrome

what is SIRS?

in response to massive tissue injury

when does SIRS occur?

an exaggerated defense response- the release of large amounts of cytokines and oxidants

what does SIRS cause?

fever

rigors

myalgia

headache

nausea

acidosis

low blood pressure

organ damage

MODS- multiple organ disfunction syndrome

death

what are the symptoms of SIRS?

E. coli, salmonella

what are the most common bacteria that cause SIRS?

SIRS- systemic inflammatory response syndrome

what disease may occur in response to massive tissue injury?

because of SIRS (systemic inflammatory response syndrome)-

the bacteria somehow triggered the body to induce a very exaggerated immune response, which is too much for the body. it leads to MODS- multiple organ disfunction syndrome, which causes death

why is an immune response causing death?

SIRS-

the bacteria Staphylococcus aureus has ensotoxins (staphylococcal toxic shock syndrome toxin) which interfere with the macrophage-T helper cell communication, causing the overproduction of cytokines, and therefore and extreme immune response that results in death

what problem does this represent?

foreign material is not completely destroyed

chronic inflammation occurs if...

-macrophages, fibroblasts, and lymphocytes accumulate

-giant cells are formed to try to ingest the particles

-fibrosis- cells deposit collagen in infected tissues

-granuloma (a cluster of WBCs and other tissue) forms

if foreign material is not completely destroyed, chronic inflammation occurs. what exactly happens?

chronic inflammation-

accumulation of WBCs to attempt to ingest the invador, and fibrosis occurs

what causes a granuloma to form?

C3

what is the most important component of the complement system?

usually the adaptive immune system- the immune complexes bind to CIq

OR the innate immune system- C3b binds to the the microorganism surface

what activates the complement system?

yes, it can distinguish self from nonself

does the complement system have self-recognition?

25-30

how many proteins are involved in the complement system?

a cascade of proteolytic reactions on microbial surfaces- coats the microbe with fragments that are recognized by macrophages

the activation of the complement system activates.....

no, only microbial invadors

does the complement system also act on infected host cells?

defends against pyogenic bacterial infections

bridges/connects innate and adaptive immune systems

assists in disposing immune complexes

what are the roles of the complement system?

the coating of bacteria with a protein (usually C3b in the complement system) so that it can be recognized by a phagocyte

what is opsonization?

opsonizes microbes

what does C3b do (part of the complement system)?

causes inflammation by causing mast cell degranulation

what does C3a do (part of the complement system)?

C3a

what part of the complement system causes mast cell degranulation?

opsonization- C3b

inflammation (by degranulating mast cells)- C3a

cytolysis- C5-C9

what are the 3 functions of the complement system?

cytolysis- they form a membrane attack complex- a pore in the target cell that causes the breakdown of the cell

what do C5-C9 do in the complement system?

complement system

what system does this represent?

C5-C9

which are the complement proteins here?

cytolysis

what is this action called?

local arteriolar vasodilation and increased local capillary permeability, which leads to increased blood delivery to the tissue and accumulation of fluid, which increases plasma proteins and phagocytes in the area for a defense response

what is the purpose of mast cells releasing histamine?

-activation of coagulation and complement system

-increased regulation of acid metabolism

-release of proinflammatory factors (C3a, C5a)

-activation of macrophages, which release proinflammatory cytokines (IL-1, IL-6, TNF)

what exactly occurs during innate immunity?

-accumulation of mononuclear cells

-antigen processing and presentation

-immune recognition

-activities of T cells and B cells

what exactly occurs during adaptive immunity?

reparation:

-elimination of insult

-decreased immune functions

-immune memory

-activation of fibroblasts

-repair of blood vessels and skin integrity

-elimination of inflammatory cells

-scar formation

after the adaptive immune response is successful, what must occur?

fever

what is the most common symptom of systemic immunity?