immunity 2 Flashcards
what is the chemical response phagocytes undergo in response to injury
inflammatory response
what does a chemical response by phagocytes cause
Injury is temporarily repaired – and additional pathogens are prevented from entering the wound
Spread of pathogens away from the wound is slowed
A wide range of defences are mobilised to overcome the pathogens and aid permanent repairs = regeneration
what does inflammation cause
Vasodilation and increased blood flow
Increased vascular permeability
Release of inflammatory mediators
Neutrophil chemotaxis - process in which neutrophils migrate towards chem signals
Microvascular coagulation - prevents loss of blood from injured sites
Systemic features - feverand raisedinflammatory markers such as CRP
Upregulation of cell surface molecules (co-stimulatory) such as MHC-II.
INFLAMMATION PROCESS
Chemical signals (histamine) released by activated macrophages and mast cells at the injury site cause nearby capillaries to dilate (widen) and become more permeable
Fluid, antimicrobial proteins, clotting elements move to the site for clotting to begin
Chemokines released by macrophages and mast cells in the tissue attract phagocytic cells to the site
Neutrophils are the first to arrive in numbers and together with macrophages they clear pathogens and debris to aid tissue repair.
what are cytokines and their function
released by immune cells in response to evidence of infection, mediating the acute inflammatory response
what molecules are cytokines
interleukins
tumour necrosis factors
chemokines (chemotaxis)
what are interferons
chem messengers that coordinate the defences agaianst viral infections
theu are small proteins released by activated lymphocytes,macrophages and tissue cells infected by viruses
stimulate the activities of macrophages and NK cells
what is the complement system
collection of 40 plasma proteins of an enzymatic receptor and regulatory nature
function together to attack pathogens directly and using inflammation
where are complement componnets produced and where do they circulate
produced by the liver
circulate in the plasma in an inactivated form before entering infected tissues, where they are enzymatically cleaved and actiavte other downstream complment proteins as part of the complemnt cascade
compliment cascade
form a cylindrical protein complex that punches holes in bactrial cell membranes - so they leak and die
what are prostaglandins
bioactive lipids that modulate immune cell function and response
pgs and inflammation
PGs regulate the initiation, activation, maintenance, and resolution of Type 2 inflammation, which can occur in response to parasitic helminth infection or exposure to allergens.
pgs and humoral immune responses
PGs can modulate humoral immune responses such as B-cell activation or antibody production.
pgs and cellular immune response
Blocking PG synthesis can enhance the cellular immune response.
regional hormones and pgs
PGs can act as regional hormones that influence the level of differentiation of lymphoid cells.
pgs and interactions betwee cells
PGs may be involved in interactions between thymic (T) and bone marrow (B) cells.
what is active immunity
occurs following exposure to tht pathogen - specifically exposure to an antigen
natural acquired active immunity
natural exposure to an antigen in the environement
chlostrum - first milk contains lots of antigens
artificially induced active immunity
caused by deliberate exposure to an antigen
vaccination
what is passive immunity
achiveed by transferring antibodies to a person from another spurce
naturally acquired passive immunity
Baby receives antibodies from the mother – either before birth across the placenta or after birth through breast milk
artificially induced passive immunity
A person is given antibodies to fight an infection or to prevent disease after exposure to the pathogen
diff between immunisation and vaccination
vaccination - getting a vaccine
immunisation - process of getting vaccine and becoming immunen following vaccination
