mcmp 422: immunology class mwf 11:30-12:20 instructors –dr. geahlen –dr. harrison –dr. hazbun...
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MCMP 422: Immunology• Class MWF 11:30-12:20• Instructors
– Dr. Geahlen– Dr. Harrison– Dr. Hazbun (RHPH 406D, 496-8228,
• Objectives• Course Policies• Grading
The Immune System
Second Edition
Chapter 1
Elements of the Immune Systemand their Roles in Defense
Copyright © 2005 by Garland Science Publishing
Peter Parham
Chapter 1Summarizes all of immunology
Get a good Foundation
Before class: Read the textbook in general and try to understand all the terminologies in bold.
During class: Take good notes because I will be adding information that will be tested
After class: Review material to commit to long-term memory
What components make up the immune system?Cells, organs, cytokines and molecules involved in the
immune system
What is the goal of the immune system?To clear pathogens and cancer cells in our body
How do we classify immune responses?Innate and adaptive immune responses
What are the side effects of the immune system?Autoimmune diseases, Allergies, Transplantation Rejection
Lecture Concepts
• Immunology: the science of how the body responds to foreign organisms (e.g. pathogens) or substances (e.g. allergen)
•Immune system: the organs, cells and molecules that defend and respond to pathogens/allergens
1. Tissues/organs
2. Cells
3. Blood borne proteins
Origin of Immunology - individuals who survived a disease seemed to be untouched upon re-exposure
Vaccination/Immunization - procedure where disease is prevented by deliberate exposure to infectious agent that cannot cause disease.
Figure 1-2
Part of body BacteriaHead (scalp) 1,000,000 /cm2Surface of skin 1000 /cm2Saliva 100,000,000 /gNose mucus 10,000,000 /gFaeces over 100,000,000 /g
How Clean are You?
• Four Classes
• Opportunistic pathogens
• Pathogen-Host relationship
Diversity of Pathogens
Defenses against Pathogens
Physical Defenses1. Skin
2. Mucosal surfaces
Immune Defenses1. Innate2. Adaptive
Figure 1-4
Pathogen Recognition
Signal
Effector mechanisms
Effector Cells Complement
Innate immunity - “naïve” everyday immunity Acquired immunity - “specialized” immunity
Immunity: Basic Parts
(Binding event)(Foreign)
(Self)
Immunedisorders
Figure 1-5 part 1 of 2
ComplementEffector cellEndocytosis
One way Immunity Works
Figure 1-5 part 2 of 2
Figure 1-6
CytokinesInflammationPhagocytosisInflammatory cells
Innate Immunity
What if Innate Immunity is not Enough?
• Innate immunity keeps us healthy most of the time
• Some pathogens escape the innate immune process
• Need a specific system to adapt to a specific pathogen
• Adaptive immune response
Figure 1-7Characteristics of Innate vs Adaptive Immunity
Lymphocytes - white blood cells that increase the immune response to ongoing infection
Innate vs Adaptive Molecular Recognition
• Most important difference: Receptors used to recognize pathogens
• Innate immunity: Receptors recognize conserved structures present in many pathogens
Pathogen-associated Molecular Patterns: LPS, peptidoglycan, lipids, mannose, bacterial DNA and viral RNA
• Adaptive immunity: Receptors recognize a specific structure unique to that pathogen
Figure 1-11 part 1 of 2Flowchart of Hematopoiesis
Figure 1-11Flowchart of Hematopoiesis
Myeloid Lineage
Figure 1-9 part 3 of 6Neutrophils:Most abundantPhagocyteEffector cells of Innate ImmunityShort-lived - Pus
Eosinophils:Worms/intestinal parasitesAmplify inflammationBind IgEVery Toxic - Pathogen and hostChronic asthma
Basophils:RareUnknown functionBind to IgE
Granulocytes (Myeloid progenitor)Polymorphonuclear leukocytes (PMLs)
Figure 1-9 part 5 of 6
Figure 1-13
Lymphoid Lineage Cells
Figure 1-9 part 2 of 6
Lymp
Figure 1-9 part 1 of 6
Erythroid Lineage
Figure 1-9 part 6 of 6
Figure 1-11 part 2 of 2Lymphoid Myeloid Erythroid
Figure 1-12
Figure 1-14
Figure 1-15
Sites of Lymphoid Tissue
Primary and SecondaryGALT, BALT, MALTLymphRecirculation
Figure 1-16
Draining Lymph nodeEdemaAfferent and Efferent
Figure 1-17 part 1 of 2
B-cell area(follicle)
Figure 1-19Anatomy of immune function in the Spleen
Figure 1-19 part 1 of 2
Figure 1-19 part 2 of 2
Figure 1-20
Adaptive Immunity
1. Vertebrates only
2. Specificity- recognition modules - BCR, Ab and TCR- gene rearrangement is the source of diversity- clonal selection
3. Small lymphocytes- types and sub-types- functions
Recognition concept
Receptor or Antibody molecule
Antigen - structure recognized by an Ab, BCR or TCR
Epitope - particular sub-structure of the Ag that is bound
Affinity - how much a molecule like to bind to a structure
B-cellsBCR is Immunoglobulin (Ig)Plasma cells - effector cells that secrete Ab
T-cellsTc = cytotoxic (CD8+)
TH = helper T-cells (CD4+)Th1 (inflammation)Th2 (help B-cells make AB)
Small lymphocyte sub-types
Recognition modules of Adaptive immunity
B cells T cells
B-cells T-cell
Figure 1-25
Intracellularpathogens
Extracellular pathogens
Figure 1-26MHC class I communicates with Tc cells
Figure 1-27MHC class II communicates with TH cells
Parasite +
Mast cell
Inflammation
Mast cell activated
Expel and/or destroy
pathogen
• Neutralization• Opsonization1. Inflammation
Parasitic infection
Principles of Adaptive Immunity
DiversitySpecificityMemorySelf-tolerance
Gene Rearrangement is the source of Diversity
Germline configuration
Diversity1. Alternative combinations2. Imprecise joints3. Different types of chains4. B-cells - somatic hypermutation
In the absence of antigen
Clonal Selection
1. Each cell = one receptor2. Millions of lymphocytes
are generated3. Small subset will
recognize a pathogen4. Proliferation and
differentiation5. Acquired immunity - the
adaptive immunity provided by immunological memory
Figure 1-22
Figure 1-30
Figure 1-31
Figure 1-28
Mechanism of Self-tolerance
Immunodeficiencies
Inherited deficiencies
Stress induced
Pathogen caused deficiencies
Figure 1-32IgGCD4 TH1CD8 CTL
Figure 1-33Insulin-Dependent Diabetes Mellitus
Figure 1-34
Figure 1-10
Figure 1-29 part 1 of 2
Figure 1-29 part 2 of 2
Figure 1-31 part 1 of 3
Figure 1-31 part 2 of 3
Figure 1-31 part 3 of 3