What is immunity?
Ability of the body to defend against infection agents, foreign cells, abnormal cells
What are the immunity system's three lines of defense?
- Physical barrier
- Innate immune system
- Acquired or Adaptive Immunity
What is a physical barrier? give an example
The immunity system's first line of defense. skin, mucus, tears
What are interferons?
- Called cytokines
- serve as signals during immune response
What are anitmicrobial agents?
Act to deter or destroy microorganisms
What is lactoferrin and transferrin and where are is each found?
- They reduce iron so bacteria can't grow (bacteria needs iron)
- Lactoferrin- milk saliva, mucus, tears
- Transferrin- blood
What is a complement?
A family of more than 20 proteins in the blood serum.
How do complements work?
- Coat pathogen so phagocytes can ingulf
- lyse cell wall
- Release substances like histamine that increase inflamation
- Attract lymphocytes to the infection site
What do phagocytic cells do?
- Engulf and devour pathogen
- uses lysozymes, nucleases, proteases etc
What are the two types of phagocytic cells?
- Stationary (macrophages) engulf cells
- Wandering (leukocytes)
What are the two types of leukocytes?
- Neutrophils- best on bacteria
- Monocytes - mobile phase of macrophage
What are the 3 nonphagocytic cells?
- Basophils- Inflammation and allergies
- Eosinophils- phagocytic and used against parasitic worms
- Lymphocytes- acquired immunity
What are natural killer cells?
Non-phagocytic cells that kill infected cells
What are lymphocytes?
T, B and NK cells and are circulated in lymphatic system and blood
What are B-lymphocytes?
- Made in bone marrow
- Naive B
- Plasma cellsm (effector)
- Memory B-
What is the Major Histocompatibility Complex (MHC)?
- Body cell antigens that identify the cells of the body as a self.
- Activates B and T cells
What are antibodies (immunoglobulins)?
Made of 2 heavy and 2 light polypeptide chains
What are the immune system disorders?
- Autoimmune disorder
- Immune-complex hypersensitivity