Pharmacology 4 - Immune System

Front 1

What are the 2 primary organs of the immune system?

Back 1

Bone marrow and Thymus

Front 2

Where does Haematopoetic cell division take place?

Back 2

Bone marrow

Front 3

What cell is the cell that all cells are derived from?

Back 3

HSC - Hematopoetic Stem Cell

Front 4

Which immune cells move to the thymus to mature?

Back 4

T cells

Front 5

What can a T cell progenitor differentiate into?

Back 5

Th, Tc or Treg

Front 6

What cells are derived from the Lymphoid Progenitor cell?

Back 6

Dendritic, NK, T cells and B cells

Front 7

What cells are derived from the Myeloid progenitor cell?

Back 7

Dendritic, Esinophils, Basophils, RBCs, Platelets, Monophages, Macrophages and Neutrophils

Front 8

What must a T cell be able to do in order to be allowed to leave the thymus?

Back 8

Differentiate non-self Ag presented by MHC

Front 9

What is the role of the spleen?

Back 9

Filter blood to trap blood-born Ag and phagocytose old or defective RBCs

Front 10

What are the 3 divisions of the spleen?

Back 10

Cortex - primary, secondary follicles for B cell maturation and DCs
Paracortex - Populated by T cells and DCs expressing MHC II
Medulla - A-b secreting cells

Front 11

What are the 3 secondary immune system organs

Back 11

Spleen, Lymph nodes and MALT

Front 12

What is and where are Peyer's patches found?

Back 12

Collections of lymphoid tissue in submucosa of small intestine and appendix

Front 13

What is a another name for MHC in humans?

Back 13

Human Leukocyte Antigens (HLA)

Front 14

What cells have MHC I?

Back 14

All nucleated cells, even ones with MHC II additionally have MHC I - Major function is Ag to Tc. Subcategories consist of HLA-A, HLA-B and HLA-C

Front 15

What cells have MHC II?

Back 15

On all APCs (Ag presenting cells) - Macrophages, B cells and Dendritic cells. Subcategories consist of HLD-DP, HLA-DQ and HLA-DR

Front 16

What are the characteristics of Non-Specific response?

Back 16

Fast, no memory, same response every time

Front 17

What cells and mechanisms participate in Non-Specific response?

Back 17

Physical barrier, NK, mono/macrophages, Mast cells, basophils, eosinophils, DCs, lysozyme, interferon and complement.

Front 18

What is the complement cascade?

Back 18

Heat labile (30) proteins, inactive in blood and when activated develop attack complex. Insert in bacteria causing loss of solutes and death. Also inflammatory and attracts WBC = increased phagocytosis

Front 19

What are neutrophils?

Back 19

First at site of inflammation, use enzymes within their granules to destroy phagocytosed material. Express TLRs, 1-3day life span and high amounts in blood circulating indicate infection

Front 20

What are eosinophils?

Back 20

Motile phagocytic cells, have a role in parasitic infections and have large granules thought to be secreted to damage parasitic membrane

Front 21

What are mast cells and basophils? What differentiates them?

Back 21

Both bind to IgE Ab on surface, activation cause degranulation and release of chemical mediators. Basophils differentiate from Mast calls as although they both release Histamine and Heparin, it also releases serotonin.

Front 22

A pollen is received by a B cell.. In terms of mast cell response, what happens next?

Back 22

The B cells differentiates into a plasma cell and secretes IgE Ab specific for that pollen. The Mast cell then attaches to the Ab, when the pollen returns and the Ag of the pollen connects with the mast cell, the mast cell will degranulate and release its chemical mediators

Front 23

What is a Natural Killer cell?

Back 23

Lymphocyte that displays cytotoxic activity against tumour and virally infected cells. It recognizes cells via their NK (down-regulation of MHC I). If down-regulated, displaying an Ag bound to their Ab, it will destroy the cell via perforin release or opsionisation. Can additionally detect abnormalities by binding to constant region of Ab that have attached themselves to affected cells (DC16)

Front 24

What is the characteristics of Specific (Adaptive) immunity?

Back 24

Highly Ag specific, slower response, can generate memory via T and B cells. Adaptive can be further divided into Humeral and Cell-mediated

Front 25

What cells are involved in the Humeral response? And what is their role?

Back 25

B cells --> secretion of Ab

Front 26

What is Cell-mediated response? And what is their role?

Back 26

T cells (Th, Tc and Treg) --> Th cells are activated after the recognition of Ag presenting MHC II. It has a TCR that binds to the MHC complex which usually displays extracellular bacteria or viral particles or Ag from dead/dying cells that have been phagocytosed.
Th cells become fully activated by the costimualtion of APC and secrete cytokines to help Tc and B cells responses + additional memory response.

Front 27

What membrane glycoprotein do Th cells display?

Back 27

CD4 only

Front 28

What is the role of Th cells?

Back 28

Secrete cytokines to help Tc and B responses + memory response.

Front 29

What subclass are Treg cells?

Back 29

Treg cells are a subclass of Th cells but can suppress immune response and thus drive tolerance.

Front 30

Which cell is most important in protection of the fetus in pregnancy?

Back 30

Treg cells

Front 31

What is the MOA of a Treg cell?

Back 31

Effects T-effector cells via inhibitory cytokines, cytolysis, metabolic disruption, blocks DCs and high levels of IL-10 to downregulate T cell response.

Front 32

What membrane glycocproteins do Treg cells display?

Back 32

CD4, CD25 and FoxP3 (intracellular)

Front 33

What membrane glycoprotein do Tc cells display?

Back 33

CD8 only

Front 34

How are Tc cells activated?

Back 34

Recognition of Ag presenting MHC I. The TLR bonds to the Ag-MHC complex of which the antigen comes from within the cell. The Ag can be intracellular virus of bacteria or tumour. Tc cells become fully activated through cytokine effect from Th cells. Once fully activated, Tc cells can kill any cells expressing its Ag via MHC I through perforin release. Can also develop a memory response.

Front 35

How are B cells activated?

Back 35

B cells have an Ab on their surface (membrane bound receptor) and can bind directly to Ag. Require Th cell for full activation and once are, can differentiate in to plasma cells (effector B cells). These cells then secrete high levels of Ab and memory B cells. The Ab subtypes are IgM, IgG, IgE, IgD and IgA.

Front 36

What is IgM responsible for?

Back 36

First response and highly expressed by immature B cells (5-10%)

Front 37

What is IgG responsible for?

Back 37

Crosses placenta to protect fetus (80%)

Front 38

What is IgA responsible for?

Back 38

Predominates mucosal secretions

Front 39

What is IgE responsible for?

Back 39

Low concentration although potent, involved in hypersensitvity reactions. Involve basophils and mast cells

Front 40

What are the (4) types of DCs?

Back 40

Langerhans - skin
Interstitial - interstitial space of organs
Monocyte-derived
Plasmacytoid dendritic cells

Front 41

What cells is the 'linker' of the innate and adaptive immune systems?

Back 41

Dendritic cell

Front 42

What are DCs?

Back 42

Express exogenous Ag via MHC I and MHC II, express CD80, CD40, CD86 for the required co-stimulated activation of bound T cells (via their CD28 receptor)

Front 43

What differentiates Immature DCs from Mature DCs?

Back 43

Immature DCs are highly phagocytic, express low levels of MHC II and high levels of cytokine receptors. They are poor immunostimulants

Mature DCs lost their ability to phagocytose, express high levels of MHC II upregulation, upregulate costimulatory molecules and can prime the immune system.

Front 44

What are Plasmacytoid Dendritic Cells?

Back 44

Highly specialized, secrete large quantities of anti-viral molecules including Type 1 IFN, IFN alpha, IFN beta.
Express TLR7 and TLR9

Front 45

What is the action of IFN alpha and IFN beta?

Back 45

To induce antiviral state by activating the JAK-STAT pathway, inducing interferon stimulated genes, RNAsel (degrades RNA), PKR (inactivation of viral protein sythesis) and binds to NK cells to induce lytic activity

Front 46

Is MHC I intracellular or extracellular Ag presenting?

Back 46

Intracelluar and by all nucleated cells to Tc cells

Front 47

Is MHC II intracellular or extracellular Ag presenting?

Back 47

Extracellular by APC to Th cells

Front 48

What does PRISH stand for?

Back 48

Pain, redness, inflammation, swelling and heat

Front 49

PPRs stands for?

Back 49

Pattern recognition receptors

Front 50

What is the key to identifying virus infection?

Back 50

Presence of nucleic acid in endosome as would occur under normal physiological conditions

Front 51

What is antigenic drift?

Back 51

Spontaneous mutations that occur over time on the viral surface of proteins (Hemagglutiinin and Neuraminidase) that changes virus slightly. The Ab in the vaccine loses its binding site after the mutation hence requires new strain

Front 52

Who are vaccines contraindicated in?

Back 52

Those with allergies to eggs

Front 53

Differentiate bacteria from virus in terms of infection

Back 53

Bacteria are outside of the cell - interstitial fluid
Virus need the machinery of a cell to replicate therefore are internal

Front 54

In sepsis, a systemic inflammatory infection, what (2) things are in high circulation?

Back 54

TNF-alpha and HMGB1 cytokines

Front 55

In sepsis, what can be given via IV from 1000-10000 donors in terms of therapy?

Back 55

Anti-TNF-alpha and anti-HMGB1 Ab to downregulate immune response

Front 56

What type of infection is malaria?

Back 56

Parasitic - Protozoan - Has a poor immune response with no memory developed. It is difficult to control as has different stages (including stages of intracellular replication)

Front 57

What is the difference between Protozoan and Helminthic organisms?

Back 57

Protozoan are single celled, helminthic are multi celled.

Front 58

What is schistosoma?

Back 58

Is a trematode worm, fresh water snail host, enzymes allow them to bore into human skin, enter capillaries --> lungs, Gi, Urinary bladder and become worms. Results in cell medicated delayed type hypersensitivity reaction from blood flow obstruction by granuloma which protects the effs layed by worms. Worm literally runs away from basophils and eosinophils.

Front 59

What type of automated body function usually deals with fungal infections?

Back 59

Commensal organisms of the body

Front 60

Which cells are critical in fungal infections?

Back 60

Phagocytic cells