Transcript The Immune System 2

The Immune System 2
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Adaptive Specific immunity (acquired) = the ability of the body to
defend itself against specific invading agents such as bacteria, toxins,
viruses, and foreign tissues.
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Specificity
Memory
Lymphocytes
T-cells and B-cells
Pluripotent stem cells
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Dual Nature of the Immune System
Lymphocytes give rise to two major types of immune
responses
1.
Cell mediated immunity
2.
Humoral (Antibody mediated) immunity
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Antigens
Immunogenicity
Reactivity
Hapten
Antigen Receptors
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Cell Mediated Immunity
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Antigen Processing
By Antigen Presenting Cells
1. Breakdown the pathogen
2. Place part of the foreign antigen on the MHC molecule
Major Histocompatibility Complex
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MHC I
MHC II
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T-cell Activation
FIRST SIGNAL
T-cell Receptors
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TCRs
SECOND SIGNAL
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Costimulation
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T-cell Activation
Clonal Selection
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Lymphocyte Differentiation
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Lymphocyte Proliferation
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CLONES:
Effector cells
Memory cells
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Antibody Mediated Immunity
B-cells
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gets a little help from her
friends – Helper T-cell
Clonal selection
Clones:
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Plasma cells and
memory B cells
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Classes of Immunoglobulins
1.
IgG
2.
IgA
3.
IgM
4.
IgE
5.
IgD
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Primary Response
Secondary Response
Autoimmune Disorders
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Study Questions:
21.21 Where do T cells and B cells develop?
21.22 What are the functions of cell-mediated immunity and antibody
mediated immunity?
21.23 How do antigens induce an immune response? Use the terms
antigen processing and antigen presentation in your answer.
21.24 What is the normal function of major histocompatibility complex selfantigens?
21.32 Outline the steps of antibody production.
21.34 How do the five classes of antibodies differ in function?
21.35 How do antibodies disable antigens?
21.37 How does the complement system destroy microbes?
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