Immune System Flashcards
Locations of WBCs
- blood vessels –> when there is an infection or wound , WBC can leave the veesel and go into the tissue cells
- lymph vessels –> circulate to lymph organs, where alot of them (ie. B and T lymphocytes) reside and are always on patrol (the B and T cells).
- lymph organs- tonsils, appendix, thymus, lymph nodes
What is the tissue counterpart of basophils?
mast cells, found in mucus membrane tissues (ie. GI tract and respiratory tract)
Function of histamine
- dilating blood vessels –> increases blood flow to site of injury –> inc WBC and complement TO the site of injury (red and hot sx)
- inc permeability of blood vessel wall –> making leaky capillaries –> fluid part of blood aka plasma w/ complement as well as WBC’s leak into tissue site of injury (edema and pain sx’s)
- both of these processes is to promote inflammation response to fight off an invader.
Mast cells/ Basophils and eosiniophils are able to release histamine
What is a key differentiator b/w NK cells and B/T cells, which are both [______]?
- NK cells DON’T require activation (by antigen presentation) to function
- lymphocytes
What lymphocyte is NOT part of adaptive immunity? Why?
NK cells; DOES NOT have to be activated by antigen to carry out function
What are the antigen presenting cells?
macrophages and dendritic cells
xtra notes: B cells are also such cells
General immune response switch from innate to adaptive immunity
APC (macrophages and dendritic cells) activate mature but naive helper T (CD4) cell into functional and mature active helper T cell, which is ready to :
* continue stimulation of inflammatory cells to prepare for adaptive immunity to take over
* activate B cells –> B cells proliferate –> turn into plasma B cells and memory B cells
* activate cytotoxic T cells (CD8 T cells) –> T cells proliferate –> directly kill pathogen infected cells w/ the same antigen (also can cause apoptosis virus infected cells) or turn into memory T cells
What is the link between innate and adaptive immunity? In other words, how is adaptive immunity started?
Antigen presenting cells (of innate immunity) : macrophages and dendritic cells engulf and present antigen to helper T cells (of adaptive immunity), specifically mature naive ones to turn them into mature activated ones
each helper T cell can only recognize ONE antigen of a pathogen in the whole world, which means MULTIPLE T cells can respond to DIFFERENT antigens on a SINGLE pathogen
- What is the major hormone that causes inflammation ?
- What cells release this hormone?
- How are these cells activated?
- When can inflammation occur?
- histamine
- basophils/ mast cells and eosinophils
- pathogen presence, damaged host cells, T Cells or other WBC’s.
- foreign invader -to fight off ivading harmful pathogens (ie. that enters through a cut on the skin) or during allergic rxn (recognize allergen antigen as bad) or during autoimmune rxn (recognize self antigen as bad) [ allergic and autoimmune are non pathogens aka harmless invaders.]
Where are basophils and mast cells usually found?
- circulating in blood and mucus membrane tissues, respectively.
Similarities between basophils and mast cell
- release histamine to promote inflammation
- help fight off infection by pathogen
- involved in allergic reactions (BUT mast cells have the first and biggest role w/ allergic reactions with basophils coming after)
Differences between basophils and mast cells
- one found in blood more and one found in tissues more
What do antibodies bind to?
specific target antigen of a particular pathogen [lock and key]
antibodies are proteins, another name is immunoglobulin.
This is a short living phagocyte
neutrophils
This is a long living phagocyte
eosinophils
A blood protein that counteracts a specific antigen
antibody
A foreign particle that stimulates, triggers the immune system
antigen
What normally is an antigen
a protein
on the surface of bacteria, virus, or fungi
Where do the immune cells aka WBC’s ALL originate from?
the (red) bone marrow - hematopoiesis
in long or flat bones
What is the function of the immune system?
to provide immunity and defense against disease causing foreign invaders aka pathogens
What are the two divisions of the immune system?
Innate and Adaptive immunity
The innate immune system is _____. Further explain.
NON-specific.
* the person is born with it
* there is protection against ALL foreign invaders. (non-self)
The adaptive immune system is ____. Further explain.
SPECIFIC
* the person has to be exposed to a particular pathogen before this arm of the immune system starts working –> so this is acquired
* fights against specific bacteria, fungi, or virus.
* attacking specific antigen on a specific pathogen
In general, adaptive immunity targets [______] on [______], whether the antigen be a whole pathogen or [_____] part of the pathogen and forms [_____] cells that remain in the blood in case a pathogen shows up again
- specific ANTIGENS
- specific pathogens
- protein
- memory
What is the first line defense of innate immunity?
- the surface physical barriers that prevent entry into the body tissues and blood. [barriers are outside the body OR inside the body but OPEN to the outside world]
What makes up the first line innate immunity?
- unbroken skin- acidity (along with vaginal, stomach, and urine acidity); oils with microbial fatty acids; normal flora prevents pathogen colonization
- hair, earwax
- mucus membranes- GI, respiratory, urinary, reproductive tracts, conjunctiva. ; normal flora prevent pathogen colonization
- associated protected chemicals (lysozymes that are present in saliva, tears, sweat of skin, and stomach) and mucus
- mutually beneficial microorganisms
Where are the mucus membranes located?
GI, respiratory, urinary, reproductive tracts, conjunctiva
What is the purpose of the mucus in innate immunity?
sticky to trap particles, then the cilia in teh trachea sweeps the mucus that has the pathogen out through our throat and mouth and it doens’t get into our lungs.
