Immunity Notes
Quarter 4 Week 3
Immune Response
• There are 2 categories of immunity
• Specific and Non Specific
Nonspecific immunity
• Nonspecific immunity includes things that protect
your body continually no matter what is trying to
enter. Here are some examples.
• 1. Skin
• 2. mucus membranes
• 3. hair, tears, ear wax
• 4. inflammatory response
• 5. macrophages –White blood cells that engulf
and digest antigens
Specific Immunity
• Specific immunity only protects your body
against one particular pathogen. For
example Chicken pox
• There are 2 branches of Specific Immunity
• 1. Cell mediated (T cells)
• 2. Antibody mediated (B cells)
Antibody Immunity
• B Cells are cells in your immune system
that make antibodies.
• They do not directly attack cellular
pathogens, but instead make antibodies
to mark the pathogens for destruction.
• Types of B Cells include: Memory B cells
and Plasma cells
Plasma cells
• Plasma cells make antibodies specific to
only one particular antigen.
• Once antibody levels in the blood are
established the plasma cells die and only
cell left are MEMORY B Cells.
Memory B Cells
• Memory B cells remain circulating in the
blood stream.
• If the body is exposed to the same antigen
in the future the body can quickly respond
and kill the antigen. This is the basis of
VACCINES
Cell mediated Immunity
• There are 4 main types of T Cells: Helper
T cell, Cytotoxic T cell, Suppressor T cell,
Memory T cell
• Helper T cells –
• Turn on the immune response. They alert the immune system that a
pathogen is present and allow the immune system to mount an
attack.
• Aids attacks helper T cells and that is the reason people with aids
die of unrelated infections that their bodies should be able to fight
off.
Cell mediated Immunity
• Cytotoxic T Cells
• Also called Killer T cells
• Kills viruses that have invaded the cell
• Also kills cells that have become Cancerous
• Suppressor T Cells
• Slows or stops the activity of T and B Cells
• Turns off the immune response.
Cell mediated immunity
• Memory T Cells
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Exist in the body for years after
Enable the body to respond quickly and efficiently to subsequent infections
or meetings with the same antigen.
Passive and Active Immunity
• Active immunity
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When you encounter and antigen and produce antibodies against them.
Can be Naturally or Artificially acquired
Artificially acquired – When we receive vaccines
Naturally Acquired – During bacterial or viral infections in which we
develop symptoms of the disease and suffer.
Active immunity you get to keep for life. Exception: some vaccines
require booster shots.
Vaccines contain dead or attenuated (weakened) pathogens that will
provoke the immune system to make antibodies.
Passive and active immunity
• Passive immunity
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Antibodies are obtained form the serum or immune system of an human or
animal immune donor. Not made by your own plasma cells
Short lived – passive immunity will only last about 1 month
Natural passive immunity – passed from the mother to the baby either
through the placenta or breast milk
Artificial passive immunity – receive immune serum or gamma globulin’s
from a donor. Ex hepatitis or rabies and antitoxins to things like snake bites.
Malaria