Module 2: Lecture 5 Flashcards
what is essential to start the adaptive immune response?
the innate immune cells
what occurs every time, everywhere you have an infection? What does it help with?
inflammation
- helps us get rid of the pathogen
- help us repair and regenerate tissue
what is inflammation?
- redness, swelling, painful
- innate, nonspecific response to tissue injury
- recruitment of phagocytes to invaded or injured area
every tissue with no exception will have ______ and will have _______ ______ ____.
- macrophages
- resident immune cells
when there is an injury, inflammation recruits phagocytes to the invaded or injured area to do what?
- isolate, destroy or inactivate the invaders
- remove debris (macrophages are really good at eating pathogens)
- prepare for subsequent healing and repair
what are our most important cells to activate inflammation?
macrophages
what cell is first alerted to the presence of a pathogen or injury?
macrophages
when macrophages engulf pathogens in innate immunity, what do they secrete?
cytokines and chemotaxins
what does activated mast cells release?
histamine
what does histamine do in innate immunity?
dilates local blood vessels and widens the localized capillary pores. the cytokines cause neutrophils and monocytes to stick to the blood vessel wall
what does chemotaxins attract? what do they do?
- attracts neutrophils and monocytes, which squeeze out between cells of the blood vessel wall (called diapedesis) and migrates to the infection site
what is diapedesis?
when neutrophils and monocytes squeeze out between cells of the blood vessel wall
when neutrophils and monocytes migrate to the infection site in innate immunity, what do they do?
monocytes enlarge into macrophages. the macrophages and neutrophils engulf the pathogens and destroy them
what happens when the epithelial cells of a capillary dilate during innate immunity?
cells and fluid are going to leave the capillary. the cells help to destroy the pathogens and the fluid (plasma) is going to cause the inflammation
why is inflammation red?
- increased capillary size and some RBCs exit
why is inflammation hot?
cytokines. they increase temperature
when does the inflammation response differ?
- it is similar no matter what the triggering event. whether it is sterile or from pathogens
- what is the inflammatory response initiated by?
resident tissue macrophages that release cytokines and chemokines
what is edema?
swelling
does inflammation have a clotting factor?
yes. to make sure no more pathogens enter
what is emigration?
the recruitment of leukocytes (neutrophils and monocytes)
when the macrophages and mast cells call for recruitment to an infected area during innate immune response, where is the backup coming from?
the blood
- neutrophils and monocytes are the backup
what do complement proteins do?
bind to the surface of pathogens
- when they bind, they can either punch holes in the surface and kill them, or allow our immune cells to phagocytosis them better
what do cytokines do?
they kill microbes directly
- allow cell movement
raise or infuse fever
what are the three major cytokines?
- interleukin 1 (IL 1)
- interleukin 2 (IL 2)
- TNF
what do the three major cytokines do?
- EP (endogenous pyrogen) induces fever in the body
- decrease plasma concentration of iron
- stimulate release of acute phase proteins (eg. CRP) of the liver to cause systemic inflammation
- trigger clotting and anticlotting systems to seal off an infected area
why do we want to lower iron in our plasma via cytokines?
because bacteria cannot source their own iron. they steal our iron to grow
- what is the ultimate goal of inflammation?
to repair the tissue
- cell division replaces lost cells with same kind of cells
what is the ultimate goal of inflammation in non-regenerative tissues like nerve and muscle?
lost cells are replaced with scar tissue (collagen)
how is your inflammation reaction measured?
because on the threat
what can be caused by prolonged, unwanted, chronic inflammation?
- Alzheimer’s disease, atherosclerosis, asthma, diabetes, cancer
- medicine for inflammation: NSAIDs, glucocorticoids
what are interferons?
very good innate immune response to end viral presence
- they go and activate a large program of gene transcription in the cell and prevent or limit the spread of the virus
- either cause the cell to self-destruct or cause it stop making more proteins
what are complement proteins made by?
the liver
what cells make gamma globulins?
B cells or plasma cells
are all plasma proteins made in the liver?
yes, except for gamma globulins
what is the complement system?
- a nonspecific response
- composed of plasma proteins that are produced by the liver and circulate in inactive form
what are the three mechanisms of activation of the complement system?
- spontaneous activation on microbial surfaces
- binding to carbohydrate chains (sugar) present on surfaces of microorganisms but not on human cells
- activation by antibody binding to antigens on pathogens
what are the two main ways the complement system causes destruction of a pathogen once activtated?
- forms membrane attack complexes (MAC) that punch holes in the pathogen (fluids will move in and out, killing the pathogen)
- enhances the uptake of the pathogen by phagocytes (opsonization)
can phagocytosis be enhances by receptor mediated endocytosis?
yes because if a pathogen is coated by complement proteins, phagocytes have receptors for those complement proteins and then now enhance the phagocytic ability
are dendritic cells, resident immune cells?
yes
how does T-cells get activated when?
when a dendritic cell takes the pathogen, chops it into small peptides, combine it with a protein and put it into the surface of the dendritic cell
can a T-cell be activated without a dendritic cell?
no
which dendritic cell in tissue have very high ability to internalize particles? (macropinocytosis)
immature dendritic cells
what causes the maturation of a dendritic cell?
encounter with a pathogen
what cell is a profession antigen presentation cell?
dendritic cells
how do dendritic cells migrate to regional lymph nodes?
via lymphatic vessels
