1-14 Cohen Overview Of Immune System

Front 1

What is the immune system?

Back 1

A bunch of cells throughout the body whose purpose is to recognize invading microorganisms, attack them, and eliminate them.

Front 2

The immune system responds to ___ which by definition are

Back 2

antigens

any antigen is a molecule that is non-self. The immune system attacks the non-self antigen: the foreign.

Front 3

When the immune system attacks infectious agents it's an example of ...?
if it's a tumor...?
Innocuous substances?
grafted organs?
self organ?

These are all examples of a ___ immune response

Back 3

protective immunity
tumor immunity
allergy
rejection
autoimmunity

normal- it's normal operations even if outcome is detrimental

Front 4

The immune system responds to microbes in a manner ___ to the type of pathogen. The manner in which it responds is different for bacteria or fungi, so that choice is ___.

Back 4

tailored

critical-- if you don't respond right, the immune system generates the wrong kind of immune response and it doesn't work --> super bad infection

Front 5

Can you name them?

Back 5

Front 6

All of these EXCEPT ___ are in the ___ immune response

Back 6

lymphocyte is not in the innate immune response

Front 7

Innate immune response is equivalent to the ___ inflammation response we learned about

Back 7

acute

Front 8

Lymphocytes then are part of the ___ immune response

Back 8

adaptive

Front 9

We identify two types of lymphocytes:

Back 9

the T cells and B cells

Front 10

The immune system is considered ___ meaning cells are everywhere though they are ___ in certain tissues like:

Back 10

systemic
concentrated or accumulated
bone marrow and thymus

Front 11

T/F: Most immune cells are in the primary lymphoid tissue like bone marrow and thymus.

Back 11

No.

They are concentrated in these organs (more concentrated than other places), but in absolute number, most of the cells are out in circulation doing their jobs as immune cells

Front 12

What organs/tissues are 1o lymphoid (primary lymphoid)?

Which organs/tissues are 2o lymphoid (secondary)?

Back 12

bone marrow and thymus

adenoid/tonsils, lymph nodes, appendix, spleen, parts of small and large intestine

Front 13

What is in/happens in secondary lymphoid tissues?

Back 13

Contain only mature cells (no precursors like in primary).
This is where the immune response is initiated.

Front 14

What are lymphatics and blood circulation systems considered? Why does this matter/what is their role?

Back 14

super highway between the different tissues/organs of primary and secondary lymphoid tissues.

This is important because the cells have to find an infection, go to secondary lymphoid tissues, then go back to infection.

Front 15

Where do you find the hematopoietic stem cell?

It has the potential to become ____ making it a ___ cell.

Back 15

bone marrow

every cell in the immune system (and more)

pluripotent

Front 16

How do you identify a hematopoietic stem cell in the bone marrow?

Back 16

You use the marker CD34

Front 17

The CD markers are used to ....? (2)

Back 17

driving the immune response: interacting with other cells and extracellular matrix

Front 18

Hematopoietic stem cells can directly become 3 cell types. Name them.

Back 18

Three progenitor cells:
common lymphoid
common myeloid
common erythroid

Front 19

What does common lymphoid cell give rise to?

How would you describe then the response type that arises from the hematopoietic stem cell -> common lymphoid progenitor?

Back 19

lymphocytes, so B cell and T cell

This is the stem cell giving rise to the adaptive immune response cells.

Front 20

What does common myeloid cell give rise to?

How would you describe then the response type that arises from the hematopoietic stem cell -> common myeloid progenitor?

Back 20

Basically granulocytes (neutrophils, eosinophil, basophil) and monocytes (dendritic cell and macrophages)

This is the stem cell giving rise to the innate immune response cells.

Front 21

The erythroid cells aren't actually part of the immune system. It's made up of

Back 21

RBC and platelets

Front 22

What triggers a B cell to go into a plasma cell?

This same trigger makes T cells turn into..?

Back 22

antigen

effector T cell

Front 23

Run it back- draw out the differentiation of immune cells from the stem cell.
Bonus points if you include info on type of response and/or location.

Back 23

**Note: The NK/T cell precursor --> T cell does NOT take place in bone marrow but in the THYMUS**

Front 24

What do plasma cells do?

Back 24

Pump out the antibodies.

Front 25

The process of hematopoietic stem cell going into the different cells happens at what age?

Back 25

All ages- your entire life (though it declines in old age)

Front 26

The innate pathway is pumping out how many neutrophil cells a day?

The adaptive's T cell?

Back 26

10^10 or 10^11 number of cells made.

10^6

A lot.

Front 27

What are some of the ways innate and adaptive immunity differ?
include info about timeline, receptors, evolution (~6 things)

Back 27

Front 28

T/F: When comparing innate and adaptive immunity mechanisms, the differences lie much more with the recognition mechanisms as opposed to the destruction effector mechanisms which is basically the same for both pathways.

Back 28

True

The map shows both going to the same "common effector mechanisms for the destruction of pathogens"

Front 29

The innate immunte system is made up of ___ proteins and ___ (kind of a stupid question). It's mediating ___ inflammation.

Back 29

soluble/serum proteins and cells
acute

Front 30

In healthy skin under all ___ layers that are ___ cells aka ____. There are also ___ proteins. These are present all the time even when there is no infection.

Back 30

epithelial
effector cells or tissue resident macrophages
complement

Front 31

As soon as something breaches the epithelial layer, the macrophages are in high enough concentration that one comes in contact to trigger the complement system. That includes macrophages phagocytosing the invader and releasing cytokines like ___ which do what?

The microorganisms are also leaving behind ___ which will go out and trigger the ___ system

Back 31

IL-6, TNF, IL-1
preps vasculature (vasodilation and increased permeability) to get in neutrophils

Ag for adaptive system

Front 32

During the process of phagocytosing invaders after epithelial breach, it's really a ___ of getting rid of the invader faster than it can multiple. The injected tissues become __________ (5 descriptors).

Back 32

race

inflamed, causing redness, heat, swelling, pain

Front 33

The adaptive immunity system can be split into two categories.

Back 33

Humoral and cellular

Front 34

Humoral immunity uses what type of effector cell? What does it use for Ag elimination?
What types of pathogens does this kill?

Back 34

B cell
antibodies- circulates and finds the pathogen
Extracellular pathogens- live in body fluids and once they're phagocytized, they're effectively killed.

It makes sense that antibodies which float around kill pathogens that live extracellularly.

Front 35

The adaptive immunity's cellular immunity system uses two cell types: name them.
How does this system undergo Ag elimination?
What pathogen type is killed with this system?

Back 35

T cell's: CD4 T and CD8 T
Direct cell-cell contact (the T cell has to actually be there- not sending out floater messages like antibodies)
Intracellular ones: when they get phagocytized or for whatever reason get inside one of your cells (phagocytic ones or some parenchymal cell) they don't care- they live happily

Front 36

What is the implication and potential problem of the humoral and cellular immunity systems targeting pathogens in different ways?

Back 36

We can get rid of both kinds of pathogens, but the body has to know which system to use-- if you used a humoral immunity attack on an intracellular pathogen, it's not going to be very effective.

Front 37

When a ___ protein antigen is in it's 3D structure, it's recognized by ___. Why is that?

Back 37

native
antibodies

It makes sense because antibodies are looking for extracellular pathogens which are going to be intact.

Front 38

What do T lymphocytes recognize? Where does it find these?

Back 38

They just look for a peptide stretch from the antigen that is formed during the degradation of the antigen- never the native conformational form.

The things T cells are recognizing are actually presented on the surface of other cells- the "antigen presenting cell". This is the cell-cell contact that is required.

Front 39

The concept clonal selection means what?

Back 39

Lymphocyte repertoire is extrememly diverse in its antigen receptors-- 10^9 T and B cells looking (all the time trying to find something to fight even absent of infection). A single lymphocyte finds an invader Ag that matches it- that lymphocyte now undergoes proliferation (clones) and differentiation to effector cells.

Basically: pathogen selects lymphocyte which clones.

Front 40

The adaptive immune response to antigen is ___ at the site of antigen entry

Back 40

NOT initiated

the antigen has to migrate to a lymph node or other secondary lymphoid tissue to initiate this immune response

Front 41

What is a naive lymphocyte? What does it do?

Back 41

A cell that has the right receptor for the Ag but has not come into contact with that Ag yet. It's circulating around. When it goes through the lymph node (or whatever) where the Ag is, it finds it, but now has to go back to the site of infection which is kind of a journey.

Front 42

How does the lymphocyte get to the site of infection after finding its Ag?

What is critical in this process?

Back 42

It goes through the lymphatic drainage to get back into the blood, go back into circulation, and make their way to site of infection to eliminate it.

The circulation is critical for an effective adaptive immune response.

Front 43

There are three types of naive lymphocytes: name them.

Each one becomes a different type of effector cell: name them.

What does each of those effector cell types secrete?

Back 43

naive CD4 -> helper T cell -> cytokines (hormonal like proteins that affect surround cells)
naive CD8 -> cytotoxic T cell (aka killer T cell) -> cytotoxins to kill
naive B cell -> plasma cell -> antibodies (circulate and contribute to killing of target)

Front 44

Describe the kinetics of the adaptive responses in a relative fashion of the pathogen specific response during a primary response and secondary response.

Back 44

First 5-7 days is a lag phase.

The effector function accumulates and increases in the body. When the antigen is gone, it plateaus and then decays, but doesn't go down as far as before-- there is a residual response- "immunological memory"

For secondary immune response: lag phase much shorter and response is much more vigorous.

Front 45

Describe the kinetics of the innate responses in a relative fashion of the pathogen specific response during a primary response and secondary response.

Back 45

Lag is very very short. It peaks, and when organism is gone, it immediately decays. There is no memory.

The next time that organism appears, it is the exact same pattern of reaction.

Front 46

it's beautiful, isn't it?

Back 46

Yes.

Front 47

___ immune reactions can cause injury to normal tissue via two types of reactions-- explain each one

Back 47

Excessive/abnormal reactions

Hypersensitivity: exaggerated immune response to foreign antigen which causes indirect injury to normal tissue (pollen or food)

autoimmune reactions: abnormal immune response to self molecules which causes direct injury to normal tissues

Front 48

In a normal situation, autoimmune reactions don't happen because of ___

Back 48

tolerance

(it's easy to remember this term because the whole "attack anything foreign!!" sounds like racism, and common anti-racism phrases are things like "increasing tolerance in the workplace")