Module 11: Innate Immune System

• innate immunity: always present, first line of defense
• what are the 2 main components of innate immunity?

  phagocytosis and inflammatory response
• acquired immunity: adapts to pathogens, increases over time
• what are the 2 main components of acquired immunity?

  antibody mediated immunity (B cells) and cell mediated immunity (T cells)
• how does the immune system identify itself?

  creates lymphocytes that respond to macromolecules
• antigens: cause immune response in host by interaction with specific receptors on lymphocytes
• what molecule is the strongest antigen?

  proteins
• primary tissues: create and educate immune system
• where do immune cells originate?

  in bone marrow
• where are immune cells educated?

  bone marrow, thymus, or MALT tissues
• secondary tissues: house immune cells that participate in defense
• Which systems are primary tissues?

  thymus, spleen, bone marrow, MALT

  
• which systems are secondary tissues?

  spleen, lymph, MALT, lymphatic

  
• innate immunity recognizes MAMPS and DAMPS
• MAMPS: macromolecules unique to microbes
• MAMPS are recognized by pattern recognition receptors: recognize foreign particles and notify immune system
• DAMPS: indicate cell damage, immune system binds and induces inflammation
• where do white blood cells originate from?

  bone marrow stem cells, determined by cytokines
• which white blood cells are generated from bone marrow stem cells?

  A) T cells

  B) B cells

  C) Monocytes

  D) neutrophils

  
• physical barriers in skin:

  1. hair
  2. glands
  3. epithelial cells
• how is hair a physical barrier?

  tightly packed cells, hydrophobic and dry (unfavorable conditions)
• how are sebaceous glands a physical barrier?

  secrete hydrophobic oils
• how are epithelial cells a physical barrier?

  produce peptide antibiotics
• examples of movement as physical barriers:

  • blinking
  • cilia in throat and lungs
  • peristaltic action in intestine
  • flow of urine in urethra
• complement: enzymatic system, circulates in bloodstream until activated
• classic pathway: antibody binds to target cell, c1 protein recognizes and forms complex
• alternative pathway: semi-active c3 protein enters pathogen membrane
• what happens if a semi-active c3 protein enters host membrane?

  proteins prevent further activation
• MB-lectin pathway: binds with mannose on pathogen surface to imitate c1, joins with c2 protein
• c3a and c5a: chemoattractants for phagocytes, bind to mast cells and induce inflammation
• c3b: binds to phagocytes
• c5b and c6-9: form pore in microbe membrane
• c8 and c9: form phospholipase to degrade membrane lipids
• label the results of the complement pathway

  A) c3a, c5a

  B) c3b

  C) c5b, c6-9

  
• inflammation: initial response to pathogen, focuses immune response
• what is the first step of inflammation?

  vasodilation and increased vascular permeability provides access to tissue
• what are the triggers of inflammation?

  damage, immunological reactions, and infection
• what are the 4 signs of inflammation?

  swelling, redness, heat, and pain
• swelling: fluid passing through gaps between capillary cells
• redness: flow of blood into area