Deck 13: Host Defenses Ii: Specific Immunity and Immunization

Question 1

CA S E FIL E

Too Much of a Good Thing
I was working in a neurology unit when a young woman named Stacy was admitted. Stacy was 24 years old. She was married and had a 2-year-old at home. She was a full-time student, studying social work at the local university.
Stacy had been referred to one of our neurologists by her family doctor with some unusual symptoms. Over the past several months, Stacy had been experiencing increasing fatigue that she described as akin to "walking under water." She had to walk considerable distances on campus and she was finding it very difficult to climb stairs. She complained of blurred vision and her eyelids sagged. She had lost weight and stated that eating was "too much effort." She ate mainly soft foods that were easy to chew because eating meat and other foods that required a lot of chewing took too much effort. Her facial expression was fixed-even smiling took too much energy. Stacy and her family were very frightened by her symptoms.
She was examined by the neurologist, who immediately suspected myasthenia gravis. He admitted her to the unit and ordered several tests to confirm the diagnosis, including a blood test for acetylcholine receptor antibodies, an electromyography, and nerve conduction studies. A CT of the chest was also ordered. Fifteen percent of patients with myasthenia gravis have a thymoma, or a tumor on the thymus.
The CT showed the presence of a thymoma, and the other tests were all indicative of myasthenia gravis. Stacy was scheduled for a thymectomy. She was also started on prednisone and neostigmine.
Following surgery, Stacy gradually improved, although she stated that fatigue continued to be a problem; however, she noticed an overall improvement in muscle strength. She was able to continue her education on a part-time basis with scheduled rest periods.
• What is the underlying cause of myasthenia gravis?
• How do immunosuppressant drugs improve symptoms in myasthenia gravis?

Answer 1

Myasthenia Gravis (MG) is a chronic neuromuscular autoimmune disorder. In this condition the circulating antibodies cause weakness by blocking acetylcholine receptors (AChR) at the post-synaptic neuromuscular junction. This in turn inhibits the stimulative effect of the neurotransmitter acetylcholine (ACh).
Myasthenia Gravis is treated with cholinesterase inhibitors, or immunosuppressants like Edrophonium and Pyridostigmine. There is no complete cure for this condition. However, treatment with immunosuppressants is effective in lessening symptoms of double vision, muscle weakness, speech difficulties, and drooping eyelids, swallowing, chewing, and breathing.

Question 2

Critical thinking is the ability to reason and solve problems using facts and concepts. These questions can be approached from a number of angles and, in most cases, they do not have a single correct answer.
Describe the major histocompatibility complex, and explain how it participates in immune reactions.

Answer 2

The Major histocompatibility complex is used to identify antigens on the surface of cells using protein makers. Class-I major histocompatibility complex molecules will present self-antigens, so the immune system will not attack the cell. The Class-II major histocompatibility complex molecules are located on macrophages, B-cells, and dendritic cells. They present non-self-antigen to immune system to attack.

Question 3

Describe how the third line of defense is different from the other two.

Answer 3

The third line of immune defense is different than the other two because it is specific to that antigen. The body has already encountered this antigen before and created memory cells that will only attack that specific antigen. The other two lines of defense are not specific to an antigen; they will attack any foreign body they encounter in the body.

Question 4

Select the correct answer from the answers provided. The primary B-cell receptor is

A) IgD.
B) IgA.
C) IgE.
D) IgG.

Question 5

The major histocompatibility complex (MHC) is a gene complex that gives rise to a series of glycoproteins (MHC molecules) found on all cells except
a. red blood cells.
b. white blood cells.
c. plasma cells.
d. B cells.

Question 6

This question connects previous images to a new concept.
From table 13.9. In this figure describing primary and secondary responses to antigen, indicate where a vaccination might be most effective, and also indicate where natural infection would play a role.
Reference: table 13.9

Question 7

Critical thinking is the ability to reason and solve problems using facts and concepts. These questions can be approached from a number of angles and, in most cases, they do not have a single correct answer.
Explain the clonal selection theory of antibody specificity and diversity.

Question 8

Compare the terms antigen, immunogen, and epitope.

Question 9

Select the correct answer from the answers provided. In humans, B cells mature in the _________ and T cells mature in the _________.

A) GALT; liver
B) bursa; thymus
C) bone marrow; thymus
D) lymph nodes; spleen

Question 10

In reviewing a client's history, the nurse notes that the client's blood type is O-negative. The client's blood type is based on the presence or absence of
a. haptens.
b. alloantigens.
c. immunogens.
d. lipoproteins.

Question 11

Critical thinking is the ability to reason and solve problems using facts and concepts. These questions can be approached from a number of angles and, in most cases, they do not have a single correct answer.
Describe three ways that B cells and T cells are similar and at least five major ways in which they are different.

Question 12

List the four stages of a specific immune response.

Question 13

Select the correct answer from the answers provided. The cross-linkage of antigens by antibodies is known as

A) opsonization.
B) a cross-reaction.
C) agglutination.
D) complement fi xation.

Question 14

Which characteristic is associated with passive artificial immunity?
a. long-term protection duration
b. requires several days to develop protection
c. immediate protection
d. creation of memory in response to antigen exposure

Question 15

Critical thinking is the ability to reason and solve problems using facts and concepts. These questions can be approached from a number of angles and, in most cases, they do not have a single correct answer.
Describe the actions of an antigen-presenting cell.

Question 16

Discuss the role of cell markers in the immune response.

Question 17

Select the correct answer from the answers provided. T- __________ cells assist in the functions of certain B cells and other T cells.

A) sensitized
B) cytotoxic
C) helper
D) natural killer

Question 18

Critical thinking is the ability to reason and solve problems using facts and concepts. These questions can be approached from a number of angles and, in most cases, they do not have a single correct answer.
a. Describe the structure of immunoglobulin.
b. What are the functions of the Fab and Fc portions?
c. Describe four or five ways that antibodies function in immunity.

Question 19

Describe the major histocompatibility complex in two sentences.

Question 20

Select the correct answer from the answers provided. T C cells are important in controlling

A) virus infections.
B) allergy.
C) autoimmunity.
D) all of these.

Question 21

Summarize the maturation process of both B cells and T cells.

Question 22

Select the correct answer from the answers provided. Which of the following can serve as antigen-presenting cells (APCs)?

A) T cells
B) B cells
C) macrophages
D) dendritic cells
E) b, c, and d

Question 23

Draw a diagram showing how lymphocytes are capable of responding to nearly any epitope imaginable.

Question 24

Select the correct answer from the answers provided. A vaccine that contains parts of viruses is called

A) acellular.
B) recombinant.
C) a subunit.
D) attenuated.

Question 25

Describe the structures of the B-cell receptor and the T-cell receptor.

Question 26

Select the correct answer from the answers provided. Conjugated vaccines combine antigens and

A) antibodies.
B) adjuvants.
C) epitopes.
D) foreign proteins.

Question 27

Outline the processes of clonal selection and expansion.

Question 28

List characteristics of antigens that optimize their immunogenicity.

Question 29

Describe how the immune system responds to alloantigens, superantigens, and allergens.

Question 30

List the types of cells that can act as antigen-presenting cells.

Question 31

List the three major types of cells that T cells will differentiate into after stimulation.

Question 32

Describe the main functions of these three types of T cells.

Question 33

Note the similarities and differences between gamma-delta T cells and the other T cells.

Question 34

Diagram the steps in B-cell activation, including all types of cells produced.

Question 35

Make a detailed drawing of an antibody molecule.

Question 36

Explain the various end results of antibody binding to an antigen.

Question 37

List the five types of antibodies and important facts about each.

Question 38

Draw and label a graph-with time on the horizontal axis-that shows the development of the primary and secondary immune responses.

Question 39

List and define the four different descriptors of specific immune states.

Question 40

Discuss the qualities of an effective vaccine.

Question 41

Name the two major categories of vaccines and then the subcategories under each.

Question 42

Explain the principle of herd immunity and the risks that unfold when it is not maintained.