Introduction to Immunology

1. Leukocytes
   1. Have nuclei and involved in phagocytosis, inflammation, adaptive immune response
2. Platelets
   1. Do not have nuclei and involved in inflammation and blood clotting

1. Cardiovascular System
   1. Include heart and blood vessels
2. Mononuclear Phagocyte System
   1. Network of reticular fibres and Phagocytes
3. Lymphatic Syatem
   1. Primary lymphoid organs are the production sites of immune cells and the maturation sites for immune cells in the absence of antigen
      1. Exp- Bone marrow, thymus
   2. Secondary lymphoid organs are the maturation sites for antigen-driven immune cells
      1. Exp - adenoid, tonsils, lymph nodes, spleen, mucosa-associated lymphoid tissue (MALT)

Nota:

• Innate Immune Response - Non specific - Immune components are preformed - Response magnitude is similar during the first and subsequent encounters - No memory is stored

1. Involved external physical barriers

Nota:

• Innate Immune Response - Non specific - Immune components are preformed - Response magnitude is similar during the first and subsequent encounters - No memory is stored

1. Internal physiological barriers and create hostile environment for the invaders
   1. Antimicrobial proteins
      1. The complement system
         1. Classical, Lectin, Alternative
         2. Work in cascade reactions to destroy phatogens
      2. Interferons
         1. Cytokines involved in immune regulation, particularly against viruses
      3. Iron-binding proteins
         1. Some bacteria employ siderophores, to "steal" iron from host proteins
      4. Antimicrobial peptides
         1. Short proteins, kill bacteria by inserting themselves into the membrane
         2. Bacteriocins, Defensins, Magainins, Protegrins
   2. Phagocytosis
      1. They possess lysosome containing substances
         1. Water, Lysozyme, Protease, Phosphatase, Nuclease, Lipase
   3. Fever
      1. Increased core temperature above 37'C and initiated by pyrogens
      2. Reduced iron availability
         1. Many pathogens requires iron and during fever, iron with holding occurs
      3. Inhibition of microbial multiplication
         1. Creating suboptimal temperature
      4. Increase metabolic rate
         1. Stimulate immune reations
   4. Inflammation
      1. Redness- from increased red blood circulation
      2. Heat- given off by the increased blood flow
      3. Pain- stimulation of nerve endings
      4. Oedema- swelling caused by fluid escaping into the tisssues
      5. Stage of inflamation
         1. Vasodilation cause more blod delivered and redness and localized heat
         2. Release of cytokines cause vasodilation and increase permeability of vessels
         3. Certain cytokines also increase permeability of blood vessels