1. Immune system
    • restores system balance
    • the body's defense system - foreign (external) and internal enemies
    • foreign enemies - extreme temperature environment, trauma, infection
    • internal enemies - cancer, cells not functioning properly (eg sickle cell)
    • the body's response to disease - organs and cells that help to restore health
  2. Immune system
    the group of organs that function together to protect the body from foreign and internal enemies
  3. Parts of the immune system
    • see picture in slides
    • lymphatic system - right lymphatic duct, thoracic duct, lymph nodes, spleen
    • adenoids
    • tonsils
    • thymus - only in juveniles (gone by 6 mos old in animals); produces T-lymphocytes
    • Peyer's patches - immune cells lining intestines
    • large intestine
    • small intestine
    • appendix
    • bone marrow
  4. Activities of the immune system
    • may be measured
    • exposure - allowing immune system to be in the presence of a foreign protein
    • natural exposure - eg sniffing something infectious on a walk
    • artificial exposure - eg vaccination - best for rabies as it is always fatal
    • immunity - immune system has responded to an exposure
    • humoral response - can measure antibodies
    • cell-mediated response - can't measure
    • protection - will not get sick when challenged by natural exposure
    • titers - measure the antibodies
    • feline coronal disease - high titer means cat will get sick next time it is exposed
    • C6, Lyme disease - high titer means you are sick/have Lyme disease
    • other titers - are a measure of immunity
  5. Nonspecific immunity
    • like a fence in a gated community
    • response is not dependent upon the enemy of the body
    • includes:
    • species resistance - eg cats don't get leptospirosis
    • mechanical actions - coughing, sneezing, itching, vomiting, tears
    • chemical barriers - eg ear wax
    • inflammatory response - takes over when stuff gets past physical and chemical barriers (got past gates, doors, windows and alarm is sounding)
  6. Inflammatory response indications
    • red
    • hot
    • painful
    • swollen
    • loss of function - if it hurts, you won't use it
    • - some animals can have inflammation and fever without infection (in infection, fever will rise instead of staying constant)
  7. Spectrum of pain
    tickle, itch, hurt
  8. Chemotaxis
    • chemical mediators that attract white blood cells to areas of invasion
    • see picture in slides
  9. Phagosytosis
    • cell eating, the process by which neutrophils clear the body of bacteria
    • see picture in slides
  10. Pus
    dead neutrophils (once they eat, they die)
  11. Rules of veterinary medicine
    • 80% of animals will get better without your help
    • 10% will die no matter what you do
    • 10% you can affect the outcome
    • however, you can always improve their quality of life
  12. Nonspecific response at the cellular level
    • complement - protein in blood that kills antigen after antibody attaches to (captures) it
    • lymphokines
  13. Lymphokines
    • command center of immune system
    • released by lymphocytes
    • product of T-lymphocytes (came out of thymus)
    • include interferon
    • eg
    • 1. neutrophils going to infection site
    • 2. becoming depleted
    • 3. T-lymphocytes release chemical to tell bone marrow to step up production of neutrophils
    • 4. later release another chemical to slow it down
  14. Interferon
    increases antviral activity of immune system
  15. Cytokines
    any cell can release when injured to alert immune system
  16. Lymphocytes
    2 types - B-lymphocytes, T-lymphocytes
  17. B-lymphocytes
    • don't know where they come from in mammals; Bursa of Fabricius in avians (analog of the thymus)
    • produce antibodies specific to invading antigens - can measure with titre
    • humoral immunity
    • divide when exposed to antigens, becoming plasma cells
    • plasma cells produce antibodies specific to the antigen to which they were exposed
    • others remain in lymph nodes as memory cells
    • antibodies also called immunoglobulins
    • TP (total protein) - Albumin = Immunoglobulin
  18. Humoral immunity
    • 1. antigen invades
    • 2. cell releases cytokines
    • 3. neutrophils appear and take invader to lymph nodes
    • 4. if dangerous, B-lymphocyte production is stimulated and they go through body looking for invaders
    • takes 7-10 days the first time an specific invader comes, almost immediately thereafter
  19. T-lymphocytes
    • involved in the tactical side
    • coordinate bone marrow and spleen
    • can't measure this at all
    • some animals will only respond with T-lymphocytes, so they won't titer for any diseases
    • produce lymphokines
    • interact with foreign cells
    • cell-mediated immunity
    • originate in thymus (present in juvenile animals)
    • integral in the process of identifying self vs not self
    • circulate in the blood
    • reside in lymph nodes and spleen (if lose spleen, risk of infection increases 40%)
  20. Immunity classification
    • ways to develop immunity - inherited or acquired
    • additional classifications - passive or active
  21. Inherited immunity
    • result of genetic factors that influence the developing animal prior to birth
    • can be either generic to species or individual animal
    • eg some people are immune to AIDS
  22. Acquired immunity
    result of exposure that occurs after birth - natural or artificial
  23. Natural acquired immunity
    exposure to the pathogen through normal living (get sick, then get better)
  24. Artificial acquired immunity
    • deliberate exposure to a pathogen - eg vaccination
    • eg approx 30% of people bitten by rabid animals get rabies and die
    • eg parvo - over 90% mortality rate in immune naive animals
  25. Passive immunity
    • give someone else's immunity - eg colostrum or hyperimmune serum
    • colostrum gives immunity to everything mom was exposed to
    • is lost, but, hopefully, by that time exposure wull have given you active immunity
    • horses, especially Arabians, will often fail to pass along immunity
  26. Active immunity
    • exposure - either natural or artificial
    • animal's own immune system is exposed and responds to a pathogen
    • body will remember this type of immunity
    • this is the principle behind the process of vaccination
Card Set
vet tech animal diseases intro set