1. A Brief Overview of Immunology
Dennis E. Lopatin, Ph.D.
University of Michigan

2. What’s the bottom line? Immune system recognizes foreign agents
Immune response is mounted to produce activated T cells and specific antibodies
Antibodies react with foreign agent
Activated T cells react with foreign agent
Activated T cells may influence other cells
Antibodies provide specificity to non-specific cytotoxic systems
Immune system “remembers: what it did.

3. What happens upon antigen exposure?
B lymphocytes
T lymphocytes
Virgin lymphocyte pool
PRIMARY RESPONSE
effector cells
memory cell pool
SECONDARY RESPONSE
Exposure to Antigen
(Naturally-acquired or artificial)
effector cells
memory cell pool
Activated T lymphocytes
Plasma cells
Regulatory
Cytotoxic
Antibodies

4. Polymorphonuclear leukocytes (or Granulocytes)
Where is that stuff?
Blood
Serum or Plasma
Leukocytes, Platelets and RBC
Mononuclear Cells
Polymorphonuclear leukocytes (or Granulocytes)
Serum Proteins
Immunoglobulins
Complement
Clotting factors
Many others
Lymphocytes (T cells, B cells & NK cells)
Monocytes
Neutrophils
Eosinophils
Basophils

5. What are the effector functions?
Antibody-Mediated
Ways to Destroy the Target
Complement activation
Agglutination
Neutralization
Mask receptors
Antibody-mediated cellular cytotoxicity (ADCC)
Opsonization and phagocytosis
Cell-Mediated
Cytotoxic T-Lymphocyte
Natural Killer Cells
Antibody-mediated cellular cytotoxicity (ADCC)

6. Hypersensitivity Reactions
When a good response goes terribly bad
Hypersensitivity Reactions
Reactions that are detrimental to the host
The result of autoimmunity
An atypical immune response
An inability to eliminate a pathogen
The tissues become a carrier for a hapten
Transplanted tissues are recognized