Immune system

• Immune system functions


  • Protection from invaders
  • Warding off (self vs non self)
  • Destruction (phagocytosis)
  • Mitigating (antibody production)
  • Healing and adaptation

  
• Cytokines


  Molecules involved in healing and adaptation
• Anamnestic response


  Immune response involving memory cells
• Immune system components


  • WBC
  • Antibodies
  • Cytokines
  • Complement system
  • Lymph nodes
  • Spleen
  • Tonsils & adenoids
  • Thymus
  • Bone marrow
  • Skin
  • Mucosa

  
• Weak vs overactive immune system

  • Cannot defend body
  • Opportunistic pathogens
  • Immunocompromised/Immunodeficient
  • Immunosuppressed
  • Defends itself against own body
  • Molecular mimicry
  • Epitope spreading
  • Bystander activation
  • Constant activation
  • Superantigens
  • Clearance deficiency
• Types of autoimmune disorders

  • Organ-specific
  • Systemic
  • Confirmed
  • Probable
  • Possible
  • Uncertain
• Types of hypersensitivity reactions

  • Type I
  • Type II
  • Type III
  • Type IV
• Type I hypersensitivity


  Mast-cell activation releases histamines and other mediators
• Type II hypersensitivity


  Antigens embedded in host cells cause complement activation and destruction by MAC
• Type III hypersensitivity


  Ab binds to soluble Ag, forming a circulating immune complex that lodges in a blood vessel wall and causes a local inflammatory response
• Type IV hypersensitivity


  APC activates Th1/CTL. T-cells activation macrophages and cause an inflammatory response
• Innate vs Acquired immunity

  • Born/non-specific
  • Adaptive/specific
• Passive vs Active immunity

  • Breastfeeding
  • Vaccines: Attenuated species/organisms or Epitopes
• Humoral vs Cellular immunity

  • Effectors: B cells
  • Effectors: T cells
• Ways to boost the immune system

  • Proper diet
  • Exercise
  • Healthy weight
  • Sleep
  • Vaccines
  • Avoid smoking, alcohol, carcinogens
  • Know your family tree