Immunology

Immunology

1. Innate Immune Response

   • First line of Defense
     • Skin
       • Epidermis: Dead layer, tightly packed, dry - not ideal for bacteria
       • Dermis: thick, has sweat (contains salt that inhibits growth), lysosomes, lower pH
     • Mucous Membrane
       • Lines body cavities; continuous shedding, produces mucus, lysosomes, and antimicrobial peptides
     • Normal Flora
       • Microbial antagonism
       • competes with potential pathogens
       • stimulates nonspecific immune response and makes vitamins
     • Other factors
       • tears, saliva, gastic acid, pH, mucus, hair, ear wax, cilia, urine/vaginal secretions, D+, V+
   • Second line of Defense
     • Phagocytes
       • Responds quickly and broadly
         • Granulocytes
           • neutrophils; basophils; eosinphils; mast cells
         • Agranulocytes
           • macrophages, T cells; B cells; NK cells
           • Monocytes
             • Tissue Histiocytes
             • Liver: Kupffer cells
             • Skin: Dendritic cells
             • Brain: microglia
             • Bone: osteoclast
           • Lymphocytes
             • CD8: cytotoxic; kills virus and damaged cells
             • Cd4: helper T Cells, helps CD8 and B cells
             • B cells: produces antibodies
     • Inflammation
       • Caused by microbes, physical & chemical agents that respond to tissue damage; destroys infectious agent, confines, repairs, replaces
         • Cardinal signs: redness, pain, heat, swelling, loss of function
         • Acute Inflammation: intense, short
           • Example: staphylocococcus skin infection
         • Chronic Inflammation: less intense, long time
           • mycobacterium infection
     • Fever
       • hypothalamus control body temp
   • Cells: neutrophils, eosinophils, basophils, monocytes, dendritic cells, macrophages