Download The Immune System

Fig. 43-1
Chapter 43
The Immune System
PowerPoint® Lecture Presentations for
Biology
Eighth Edition
Neil Campbell and Jane Reece
1.5 µm
Lectures by Chris Romero, updated by Erin Barley with contributions from Joan Sharp
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 43-3
Microbes
• Innate immunity
PHAGOCYTIC CELL
• Acquired immunity, or adaptive immunity
Vacuole
Lysosome
containing
enzymes
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 43-7
Fig. 43-8-1
Interstitial fluid
The human lym
mphatic system
Adenoid
Tonsil
Blood
capillary
Lymph
nodes
Spleen
Tissue
cells
Pathogen
Lymphatic
vessel
Peyer’s patches
(small intestine)
Splinter
Chemical Macrophage
signals
i
l
Mast cell
巨噬細胞
Capillary
Appendix
Red blood cells Phagocytic cell
吞噬細胞
Lymphatic
vessels
Lymph
node
Masses of
defensive cells
1
Fig. 43-8-2
Pathogen
Fig. 43-8-3
Splinter
Chemical Macrophage
signals
i
l
Mast cell
Pathogen
Fluid
Capillary
Red blood cells Phagocytic cell
Splinter
Chemical Macrophage
signals
i
l
Mast cell
巨噬細胞
Fluid
Capillary
Phagocytosis
Red blood cells Phagocytic cell
吞噬細胞
Natural Killer Cells
Innate Immune System Evasion by Pathogens
• All cells in the body (except red blood cells)
have a class 1 MHC protein on their surface
• Some pathogens avoid destruction by
modifying their surface to prevent recognition
or by resisting breakdown following
phagocytosis
• Cancerous or infected cells no longer express
this protein; natural killer (NK) cells attack
these damaged cells
• Tuberculosis (TB) is one such disease and kills
more than a million people a year
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Concept 43.2: In acquired immunity, lymphocyte
receptors provide pathogen-specific recognition
Antigen Recognition by Lymphocytes
• White blood cells called lymphocytes
recognize and respond to antigens, foreign
molecules
• An antigen (抗原) is any foreign molecule to
which a lymphocyte responds
• Lymphocytes that mature in the thymus (胸腺)
above the heart are called T cells, and those
that mature in bone marrow are called B cells
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
• A single B cell or T cell has about 100,000
identical antigen receptors
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
2
Fig. 43-15
Antibody
y concentration
(arbitrary units)
Primary immune response
to antigen A produces
antibodies to A.
Cytotoxic T Cells: A Response to Infected Cells
Secondary immune response to
antigen A produces antibodies to A;
primary immune response to antigen
B produces antibodies to B.
• Cytotoxic T cells are the effector cells in cellmediated immune response
104
• Cytotoxic T cells make CD8, a surface protein
that greatly enhances interaction between a
target
g cell and a cytotoxic
y
T cell
103
Antibodies
to A
102
Antibodies
to B
• Binding to a class I MHC complex on an
infected cell activates a cytotoxic T cell and
makes it an active killer
101
100
0
7
14
21
Exposure
to antigen A
28
35
42
49
56
• The activated cytotoxic T cell secretes proteins
that destroy the infected target cell
Exposure to
antigens A and B
Time (days)
Animation: Cytotoxic T Cells
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 43-21
Fig. 43-21a
Viral neutralization
Virus
Viral neutralization
Opsonization
Activation of complement system and pore formation
Bacterium
Complement proteins
Virus
Formation of
membrane
attack complex
Flow of water
and ions
Macrophage
Pore
Foreign
cell
Fig. 43-21b
Fig. 43-24
Opsonization
autoimmune diseases
Bacterium
M
Macrophage
h
3
Fig. 43-26
AIDS
Helper T cell concentration
in blood (cells/mm3)
Latency
Relative antibody
concentration
800
Relative HIV
concentration
600
Helper T cell
concentration
400
200
0
0
1
2
3
4
5
6
7
8
Years after untreated infection
9
10
4