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 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 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 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