Transcript Immune System

Chapter 31 Opener
Table 31.1 Innate and Adaptive Immune Responses to an Infection
Figure 31.1 White Blood Cells
Figure 31.2 Innate Immunity
Figure 31.2 Innate Immunity
In-Text Art, Ch. 31, p. 623 (1)
In-Text Art, Ch. 31, p. 623 (2)
Figure 31.3 Interactions of Cells and Chemical Signals Result in Inflammation
Figure 31.3 Interactions of Cells and Chemical Signals Result in Inflammation
Concept 31.1 Animals Use Innate And Adaptive Mechanisms to Defend Themselves against
Pathogens
Innate vs. adaptive immunity
Working in pairs and without looking at your notes, identify whether each item
below is characteristic of innate immunity and/or adaptive immunity:
1. Barriers such as skin
2. Antibodies
3. Phagocytes
4. Lysozyme
5. B cells
6. Complement system
7. Distinguishing “self” from “non-self”
8. T cells
9. Lymphocytes
10. Interferon
11. Always “ready to go”; does not need time to develop
12. Mucus
13. Found only in vertebrates
14. Can retain a “memory” of previous infections
Concept 31.1 Animals Use Innate And Adaptive Mechanisms to Defend Themselves against
Pathogens
Innate immunity includes
a. B cells.
b. lymphocytes.
c. phagocytes.
d. Both a and b
e. Both b and c
Concept 31.2 Innate Defenses Are Nonspecific
Inflammation: helping or hurting?
Working in small groups, review the following common symptoms of
inflammation that occur after tissue injury. Identify the proximate cause of
each symptom (for example, what exactly causes the injured tissue to
become warm, red, etc.). Then discuss whether you think each symptom is
adaptive—that is, does the symptom help speed wound healing or help
defend against infection?
• Heat
• Redness
• Pain
• Swelling
Finally, consider the following question: Many athletes, after an injury,
immediately take action to reduce the symptoms of inflammation, with
treatments such as compression bandages, ice, aspirin or anti-inflammatory
drugs. Given what you have discussed, do you think it is always a good idea
to try to reduce symptoms of inflammation after an injury?
Concept 31.2 Innate Defenses Are Nonspecific
Which of the following statements about inflammation is
false?
a. Mast cells release prostaglandins.
b. Dilation of blood vessels causes swelling and heat.
c. Natural killer cells release histamine.
d. Histamine increases the permeability of blood
vessels.
e. Aspirin blocks prostaglandin synthesis.
Figure 43.7 Immunological memory
Figure 31.14 Vaccination
Figure 43.6 Clonal selection
Figure 43.10 An overview of the immune responses (Layer 4)
In-Text Art, Ch. 31, p. 625
In-Text Art, Ch. 31, p. 625
Figure 31.4 The Discovery of Specific Immunity
Figure 31.4 The Discovery of Specific Immunity
Figure 31.4 The Discovery of Specific Immunity (Part 1)
Figure 31.4 The Discovery of Specific Immunity (Part 2)
Figure 31.5 Clonal Selection in B Cells
Figure 31.5 Clonal Selection in B Cells
Figure 31.6 The Adaptive Immune System
Figure 31.6 The Adaptive Immune System
Figure 31.6 The Adaptive Immune System (Part 1)
Figure 31.6 The Adaptive Immune System (Part 2)
Apply the Concept, Ch. 31, p. 629
Concept 31.3 The Adaptive Immune Response Is Specific
Antibody production
Suppose you were exposed to a new cold virus when you walked in to lecture
today. Your body has never encountered this particular virus before. The
virus is now circulating in your body, and is encountering B and T cells.
Working in pairs or small groups, discuss what would happen to your ability to
produce antibodies against this virus if you…
1. have no helper T cells at all? (Assume you still have other types of T
cells.)
2. have no B cells at all?
3. have B and T cells, but due to a genetic mutation, your developing B
and T cells never rearranged their DNA?
4. cannot produce any memory cells? (That is, suppose all of your
activated B cells become plasma cells, and none become memory
cells.)
5. have a genetic mutation such that none of your B cells will divide when
activated? (Assume the B cells are otherwise normal and functional.)
Which of the above two scenarios will produce the same (or very similar)
symptoms? Explain.
Concept 31.3 The Adaptive Immune Response Is Specific
If no helper T cells are present,
a. antibodies will be produced normally.
b. a few antibodies will be produced, but not as many as
normally would be produced.
c. no antibodies will be produced.
d. I don’t know.
Concept 31.4 The Adaptive Humoral Immune Response Involves Specific Antibodies
Build your own immunoglobulin!
Suppose you’re a developing lymphocyte. You are about to start randomly
shuffling your DNA to build a “supergene” that you will use to make an
immunoglobulin chain. You have a chromosome that contains following DNA
regions:
V1-V2-V3-V4-V5-V6…D1-D2-D3-D4-D5-D6
• Roll the dice to select one of the V regions.
• Roll the dice again to select one of the D regions.
Write down your final combination of gene segments (e.g., V3-D2, or whatever
it is). You have just spliced these gene segments together! This is the final
combination of your immunoglobulin chain.
Review with a friend:
• What will you do with your immunoglobulin chain? (Secrete it? Put it in
your membrane?) Review the different types of immunoglobulins and
their functions.
• Real B cells have 100 V genes, 30 D genes, and 6 J genes for heavy
chains, and a similar amount of diversity for light chains. How many
possible combinations are there of light chain + heavy chain?
Concept 31.4 The Adaptive Humoral Immune Response Involves Specific Antibodies
Which of the following cell types produces large numbers of
antibodies?
a. Helper T (TH) cell
b. Cytotoxic T (TC) cell
c. Plasma cell
d. Memory cell
e. Both a and c
Concept 31.5 The Adaptive Cellular Immune Response Involves T Cells and Their Receptors
MHC proteins
Working in pairs, review the differences between Class I
MHC proteins and Class II MHC proteins.
Discuss:
• Which type of cell expresses Class I? Class II?
• What type of antigen is presented on each class?
• Which type of T cell will bind?
• What will the T cell do?
Concept 31.5 The Adaptive Cellular Immune Response Involves T Cells and Their Receptors
Which of the following statements is true about Class II
MHC proteins?
a. They are found on macrophages.
b. They are used to present intracellular protein
fragments.
c. Cytotoxic T cells will bind to them.
d. Once a T cell binds to them, the antigen-presenting
cell is destroyed.
e. I don’t know.
Figure 31.7 The Structure of an Immunoglobulin
Figure 31.7 The Structure of an Immunoglobulin (Part 1)
Figure 31.7 The Structure of an Immunoglobulin (Part 2)
In-Text Art, Ch. 31, p. 630
In-Text Art, Ch. 31, p. 630
Figure 31.8 Heavy-Chain Genes
Figure 43.16 Effector mechanisms of humoral immunity
Figure 43.17 The classical complement pathway, resulting in lysis of a target cell
Figure 31.8 Heavy-Chain Genes
Figure 31.9 Heavy-Chain Gene Recombination and RNA Splicing
Figure 31.9 Heavy-Chain Gene Recombination and RNA Splicing
Figure 31.10 A T Cell Receptor
Figure 31.10 A T Cell Receptor
Figure 31.11 Macrophages Are Antigen-Presenting Cells
Figure 31.11 Macrophages Are Antigen-Presenting Cells
In-Text Art, Ch. 31, p. 634
In-Text Art, Ch. 31, p. 634
Table 31.2 The Interaction between T Cells and Antigen-Presenting Cells
Figure 31.12 Tregs and Tolerance
Figure 31.12 Tregs and Tolerance
Figure 43.18 Mast cells, IgE, and the allergic response
Figure 31.13 The Course of an HIV Infection
Figure 31.13 The Course of an HIV Infection