Lecture 7 + 8

Question 1

Where are dendritic cells normally located?

Answer 1

In the peripheral tissues and the skin mucosa tissues.

Question 2

Roles of dendritic cells.

Answer 2

Surveillance, move cells to the lymphatic system.

Question 3

What are the different parts of the lymphatic system? (4)

Answer 3

Mucosal associated lymphatic tissues, lymph nodes, spleen and thymus

Question 4

What are some mucosal associated lymphatic tissues? (3)

Answer 4

Tonsils, appendix, peyer’s patches

Question 5

When can’t PAMPS (innate immune cells) recognize the cells?

Answer 5

When the innate cells are incapsulated or when a virus changes the molecules on the surface.

Question 6

What does clones mean for B cells?

Answer 6

A group of B cells that all derive from a single parent B cell and are able to recognize each other. They undergo clonal expansion: divide rapidly to produce many identical daughter cells or clones to produce large amounts of antibodies specific to the antigen (plasma cells) or become memory B cells (have more effective responses).

Question 7

Give examples of antibody structures.

Answer 7

IgG is a monomer (basic antibody structure).
IgA is a dimer.
IgM is a pentamer.

Question 8

Describe a basic antibody structure.

Answer 8

A twofold axis of symmetry and is composed of 2 identical heavy chains and 2 identical light chains. The variable regions of a heavy and a light chain combine to form an antigen-binding site, so that both chains contribute to the antigen-binding specificity of the antibody molecule.

Question 9

What is the FC fragment? What activates this fragment?

Answer 9

What the antibody uses to interact with its effector molecules. C1 will interact with this fragment.

Question 10

What happens during the B-cell development in the bone marrow?

Answer 10

Gene rearrangement

Question 11

Describe gene rearrangement.

Answer 11

Changing segments of nucleotides… change the type of protein that is produced.

Question 12

Where does B cell diversity come from?

Answer 12

Recombination and clonal selection

Question 13

Antibodies are _________ in nature and also ______ receptors that can be secreted in serum to activate ________.

Answer 13

proteins; B-cell; complement

Question 14

What are the types of T cells?

Answer 14

Helper and cytotoxic

Question 15

Lymphocytes can be __ cells and __ cells.

Answer 15

T; B

Question 16

What are plasma cells? What do they secrete?

Answer 16

Plasma cells are the effector B cells. They are the cells that will secrete antibodies.

Question 17

What are the functions of antibodies

Answer 17

Can neutralize toxins, agglutinate (bind stuff), and activate the complement of other cells.

Question 18

Why are we able to identify T helper cells?

Answer 18

We are able to identify T helper cells because of the difference of CD4 and the CD8 molecules (that can interact with MHC) to tell us the cytotoxic cells.

Question 19

Why are APCs important?

Answer 19

APC are usually the only cell types in the body capable of producing antigen to both type I and II cytotoxic and helper cells b/c they have MHC I and MHC molecules.

Question 20

Which cell doesn’t have a nucleus?

Answer 20

Human red blood cells.
(Avian red blood cells have a nucleus)

Question 21

The majority of T cells are _________ (alpha/beta/gamma)

Answer 21

alpha/beta

Question 22

X-ray crystallographic is used for what?

Answer 22

Allows us to study the structure of proteins.

Question 23

When T cell signaling is activated, what 3 things can they do?

Answer 23

Proliferation, cytokine production and differentiation (effector and memory)

Question 24

Signaling through the TRC depends on what?

Answer 24

A complex of proteins referred to collectively as CD3

Question 25

The CD3 complex is made up of 3 dimers. What are they?

Answer 25

A delta epsilon pair, a gamma epsilon pair and either 2 CD3 zeta molecules or heterodimer.

Question 26

What kinds of bonds will the negative paths of the T cell receptors form?

Answer 26

Ionic bonds

Question 27

What will CD8 T cells recognize?

Answer 27

Antigen that is expressed on the surface of class I MHC molecules.

Question 28

CD28 is on the _____.
CD80 on the _____________ (3) for full activation to occur.

Answer 28

T cell; antigen presenting cells

Question 29

What is CD45?

Answer 29

A phosphatase which removes/cleaves the inhibitory phosphate group on the Lck

Question 30

What is one of the earliest adapter molecules to be incorporated into the signaling complex?

Answer 30

LAT which is a transmembrane protein.

Question 31

PLC1, localized to the _____________ by binding to ___, is further activated by ______________, mediated by the __________.

Answer 31

plasma membrane; LAT; tyrosine phosphorylation; kinase Itk

Question 32

Describethe release of calcium.

Answer 32

PLC1 breaks down PIP2, releasing IP3, which induces the release of calcium and the activation of NFAT via calcineurin activation