PHSC420 - intro to vaccines & overview of immunity

immunity and how it works

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immunology

the more infectious something is, the higher r not needs to be

smallpox

• significance & prevention

• effectiveness

origins & history of variolation

what is a vaccine

• vaccine history

• vaccine effectiveness

Herd immunity & Rnot

susceptibility

• factors that influence susceptibility

SUSCEPTIBILTY: the quality or state of being susceptible, especially lack of ability to resist some extraneous agent (such as a pathogen or drug)

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- General health – fatigue, nutrition
• Demographics – sex, age, race
• Chemical – pH, environmental exposure
• Stress
• Immunity – previous exposure, white
blood cell levels

Immune system

Definition: Human immune responses rely on recognition of (pathogen) molecules by (host) receptors

*the ability for it to remember (memory) is the most important part of the immune response

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THE IMMUNE SYSTEM IS:

The cells, organs, and body systems that
recognize and defend against foreign substances
• Most frequently pathogens (viruses, bacteria, fungi, parasites)
• Can be induced by mis-regulation or mistaking self as foreign (autoimmunity)

Antigen – Any substance (usually foreign) that
binds specifically to an antibody or T-cell receptor (STARTS UP THE IMMUNE RESPONSE)
• Derived from pathogens
• Can come from self
• Can be presented by other immune cells

Human immune responses (2)

• there is ____ and _____

• germ-line encoded (pattern recognition receptors)

  - The same in EVERYONE, inherited from previous generations
  - These bind to pathogen-associated molecular patterns (PAMPs)―generic molecules found on many different types of pathogens (ex: peptidoglycan)

  - Innate Immunity

• Randomly generated (B and T cell receptors)
  - These bind to very specific antigens, rather than generic molecules found on many pathogens
  - Adaptive Immunity

• innate immune response, when you initially get sick, your start coughing, sneezing with snot etc.

where do cells of the immune system cells come from?

• what are the types of immune cell

• Hematopoiesis: Formation and differentiation of blood cells

  - Myeloid progenitor: cells from the bone marrow
  - Lymphoid progenitor: cells that produce immunity mediated by cells or antibodies - ADAPTIVE

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types of immune cells

• granulocytes (ex: mast cells, neutrophul, basophils,eosinphil)

  • Contain granules that release proteins and peptides with variety of effects
    - Inflammation (Histamine)
    - Cell recruitment (Chemokines)
    - Anticoagulation (Heparin)
    - Cytokines

  • They can also present
    - Receptors that bind antibodies
    - Antigens to other cells

• myeloid antigen-presenting cells

  • Cells arising from myeloid progenitor cells that are professional antigen-presenting cells (pAPC)
    - Bridge the innate and adaptive immune systems

  • Important roles:
    - Phagocytosis and antigen presentation
    - Inflammatory mediators
    - Produce cytokines and other signaling molecules

• lymphocytes (innate that come from adaptive)

  • Principle cells of the adaptive immune system

  • 3 primary populations (B-cells, T-cells, Natural Killer cells)

tissue of the immune system: primary and secondary lymphoid tissue

PRIMARY LYMPHOID TISSUE

SECONDARY LYMPHOID TISSUE

passive vs active immunity