Cells Sem 2 Test 1 Part 2 Aquired Immunity

Front 1

WHAT ARE THE KEY FEATURES OF AQUIRED IMMUNITY

Back 1

Specificity - can be immune to one pathogen but suceptible to another

Diversity - many different antibodies and antigen specific T cells that react to different antigens
(NK cells/Eosinophils are all the same but each B/T lymphocyte is unique)

Immunologic memory - this is the basis of vaccination

Self vs Nonself recognition - mechanism to remove autoreactive immune cells to prevent you from being immune to yourself

Front 2

what is tolerance

Back 2

ability of our immune system to recognize us and not attack us. our immune system is tolerant of us but intolerant of invading pathogens

Front 3

how is an antibody and adapter

Back 3

an antibody is an adapter because it tethers pathogens to killing mechanism

Front 4

how do the variable and constant regions compare

Back 4

the variable regions of antibodies are all different
the constant regions of antibodies are practically all the same

Front 5

what does the variable region do

Back 5

it is the recognition area and recognizes the pathogen via recognition site that is compliment to a feature of the pathogen allowing it to tightly bind

Front 6

what does the biological region do

Back 6

it is the constant region and has functions that lead to death of pathogens

biological region is a toxin/toxic of the microbe and bind to the phagocyte via antibody receptor and when binding occurs there is a signal sent to the phagocyte to activate it

C3B DOES THIS TOO BY COATING MICROBES AND BINDING TO RECEPTORS ON PHAGOCYTES

Front 7

what happens in the classical compliment pathway

Back 7

C1qrs gets activated by an antigen-antibody complex or antibody-microbe complex and it becomes ACTIVE C1QRS

C1QRS OR MASP1/2 can cleave C4 into C4A AND C4B

C4B + C2 FORMS C4b2

C4b2 gets cleaved by C1QRS OR MASP1/2 to form C3 CONVERTASE

Front 8

what initiates the classical pathway

Back 8

antibodies (when C1qrs activated by antibody-antigen complex or antibody-microbe complex)

Front 9

what initiates the alternative pathway

Back 9

bacterial surfaces (C3b is stabalized when it binds to surface of bacteria)

Front 10

what happens in the clearance of antibody-antigen complexes/immune complexes via complements

Back 10

C1qrs gets activated by antibody-antigen complex

active C1qrs goes through classical complement pathway and forms C3b

C3b binds to immune complex

Immune complex binds to RBC via CR1 receptors

RBC transfers immune complex to phagocytes

Phagocytes bind the immune comples via CR1 and destroy it

Front 11

what are the negatives of immune complexes

Back 11

if they complex formation is excessive, or not cleared fast enough the complex will deposit in tissues and cause problems

Front 12

how is a toxoid made

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you deactivate a toxin with fromaldahyde which maintains the toxins shape but it is essentially dead and you then inject it into the person (this is how vaccinations are done) when exposed for the 2nd time they will have a much greater antibody response

Front 13

in cell mediated immunity what contains the compliment and antibodies

Back 13

fluid of blood

can get WBC from cellular fraction of blood

Front 14

what do B cells make

Back 14

antigen specific antibodies

Front 15

what do T cells make

Back 15

they don't make antibodies but have T cell receptors (TCR) on their surface which are antigen specefic receptors that allow T cell to recognize pathogen

TCR on antibodies are never secreted and always bound

Front 16

what is cell mediated immunity important for

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for pathogens that live inside cells b/c antibodies can't cross cell membranes

Front 17

what are some examples of intracellular pathogens

Back 17

viruses
Myobacteria (TB)

T cells are needed for defense against these pathogens

Front 18

what are the types of T cells

Back 18

T helper (TH)
T cytotoxic cells (CTL)

Front 19

what do T helper cells do

Back 19

help B cells make antibodies and w/o them your body will only make a small amount of antibodies and won't have as great of a response upon 2nd encounter

Front 20

what are CTLs

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t cytotoxic cells that kill target cells and virus infected/cancer cells

Front 21

what do T helper cells bind to

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MHCII

Front 22

what to T cytotoxic cells bind to

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MHCI

Front 23

how do T helper cells help macrophage kill pathogen

Back 23

Macrophage will process some of the virus and send it to the surface coupled with MHCII

MHCII will present the peptide to the T cell

The T cell will bind to the MHCII and a signal will be sent to the inside of the T cell to make Interferon Gamma IFNgamma

Interferon gamma acts on the macrophage and activates its killing mechanism that helps macrophage clear the pathogens

as a result macrophage makes more enzymes or reactive oxygen

Front 24

how are virus infected cells killed

Back 24

some viral proteins will be present on the surface of the cell

since the viral proteins aren't part of the virus in the cell it can make a antibody

antibodies can bind to the infected cell via the surface proteins

NK cells have FcGAMMA receptors for biological part of antibody
-NK cells become tethered to the virus infected cell and kill it via Perforin and Fasl

Front 25

what are the mechanism NK cells use to kill

Back 25

perforin and FasL

Front 26

how do NK cells participate in non specefic killing

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NK cells kill virus infected cells just because it can recognize abnormal cell surfaces