Lecture 2

Question 1

Which MHC molecule do cytotoxic T cells recognize?

Answer 1

MHC1.

The CD8 molecule binds to MCH1.

Question 1

What percentage of total lymphocytes are circulating in the blood at any one time?

Answer 1

2%

Question 1

What do monocytes mature into in the tissues?

Answer 1

Macrophages or dendritic cells.

Question 2

Is a blood lymphocyte count an accurate representation of total lymphocyes in the body?

Answer 2

No.

The majority of lymphocytes are found in the tissues.

Question 3

True or False: Basophils are covered in IgE antibody.

Answer 3

TRUE.

These cells are important in the detection of parasites.

Question 3

True or False: NK cells are antigen-specific.

Answer 3

FALSE.

NK cells are part of the innate immune system.

Question 3

Where is the antigen binding site on an antibody?

Answer 3

On the light chain.

Question 3

Identify the following cell types.

Answer 3

4. Monocyte
5. Endothelial cell
6. Neutrophil
7. Leukocyte

Question 4

True or false: leukocyte is synonymous with lymphocyte.

Answer 4

FALSE. Leukocyte refers to any white blood cell, whereas lymphocyte refers to T, B, and NK cells.

Question 5

Name the cells derived from the lymphoid cell lineage.

Answer 5

B cells, T cells, NK cells

Some dendritic cells

Question 6

Name the three lineages of hematopoeitic stem cells.

Answer 6

1. Erythroid
2. Myeloid
3. Lymphoid

Question 6

What is the normal ratio of helper T cells (CD4+) to cytotoxic T cells (CD8+)?

Answer 6

2:1

If the ratio approaches 1:1, the patient becomes immunodeficient.

Question 8

Where do dendritic cells mature?

Answer 8

In the tissues, where they act as important sentinel and antigen-presenting cells.

Question 9

What is the definition of “half life” for a blood cell?

Answer 9

The amount of time it takes for half of the cells of a particular type to be replaced in the blood stream.

Question 9

True or False: Each B cell can recognize multiple antigens.

Answer 9

FALSE

Each B cell expresses only one B cell receptor (BCR) and so can only recognize one antigen.

Question 11

Name the cells derived from the myeloid cell lineage.

Answer 11

Monocytes, eosinophils, basophils, neutrophils

Some dendritic cells

Mast cells

Question 12

What is a neutrophil’s primary function?

Answer 12

Protect against bacterial infection.

Question 13

What is the difference between cytotoxic T cell surface receptors and helper T cell surface receptors?

Answer 13

Helper T cells express CD4.

Cytotoxic T cells express CD8.

Question 14

Name the cells derived from the erythroid cell lineage.

Answer 14

RBCs and Platelets

Question 14

What is the term for an immature neutrophil released into the circulation?

Answer 14

Band cell

or

Band neutrophil

Question 16

List the secondary lymphoid tissues.

Answer 16

1. Lymph nodes.
2. Spleen.
3. MALT - mucosal-associated lymphoid tissue.

Question 18

Which leukocyte is present in the highest concentrations in the blood?

Answer 18

Neutrophil

Question 19

What is one of the first thing that happens when a lymphocyte encounters its target antigen?

Answer 19

Rapid clonal expansion (mitosis).

Question 20

True or false: You are going to kick some serious ass on the Immunology test.

Answer 20

GODDAM TRUE

Question 21

Define "addressins."

Answer 21

Adhesion molecules on the surface of endothelial cells that allow leukocytes to identify where they are in the body.

Question 22

What is the difference between alpha beta T cells and gamma delta T cells?

Answer 22

Alpha beta T cells express CD4 and CD8. Gamma delta T cells do not express CD4 or CD8.

Question 23

Which molecule is responsible for signal transduction after a T cell encounters an antigen?

Answer 23

CD3

Question 25

List the primary lymphoid tissues.

Answer 25

1. Thymus - maturation site of T cells. 2. Bursa of Fabricius - maturation site of B cells in birds. 3. Bone marrow - maturation site of B cells in primates, rabbits, and rodents. 4. Peyer's patches - maturation site of B cells in ruminants, pigs, and dogs.

Question 26

List the types of lymphocytes.

Answer 26

1. T cells. 2. B cells. 3. Nk cells.

Question 27

Which MHC molecule do helper T cells recognize?

Answer 27

MCH2. The CD4 molecule binds to MHC2.

Question 28

An animal showing an eosinophilia from blood work might have what kind of condition?

Answer 28

Parasitic infestation.

Question 30

Identify the leukocyte type.

Answer 30

Lymphocyte.

Question 31

What is meant by the term "memory cell?"

Answer 31

Long-lived clone of a lymphocyte.

Question 33

Identify the following blood cell types.

Answer 33

1. Erythrocyte 2. Basophil 3. Eosinophil

Question 34

True or False: B cells can recognize unprocessed antigens (i.e. not presented by the MHC).

Answer 34

TRUE

Question 35

Identify the components of this surface immunoglobulin.

Answer 35

1. Antigen binding site. 2. Light chain. 3. Heavy chain. 4. Trans-membrane region.

Question 36

True or false: Of all the WBCs, the bone marrow spends most of its energy making lymphocytes.

Answer 36

FALSE. Most energy is spent on making neutrophils.

Question 37

How are new antigen receptors generated by T cells?

Answer 37

DNA rearrangement while maturing in the thymus. If a newly generated receptor recognizes self antigens, the cells will quickly be destroyed.

Question 38

Lymphocytes make up what percentage of circulating white blood cells?

Answer 38

30%

Question 40

Name the leukocytes that are classified as granulocytes.

Answer 40

1. Neutrophils 2. Eosinophils 3. Basophils

Question 41

What are Peyer's patches?

Answer 41

Part of the gut-associated lymphoid tissue (GALT).

Question 42

What is the half life of an eosinophil in the bood stream?

Answer 42

30 seconds. Can live for 2 weeks in the tissues.

Question 43

What is meant by the term "neutropenia?"

Answer 43

A decreased number of neutrophils in the blood stream.