microbiology

inappropriate or exaggerated immune responses

• allergies: triggered by an antigen called an allergen
• antibodies: IgE
• response varies: a) atopy: localized response ex: hay fever, asthma (can be life threatening). b) anaphylaxis: systemic, life threatening

• sensitization: 1st time you are exposed to allergen producing IgE.  IgE bind to mast cells or basophils.
• provocative dose: subsequent exposure to allergen.
• IgE binds allergen
• causes increased in Ca+2
• increased activity of adenylyl cyclase break down cAMP
• decreased cAMP causes degranulation granules - histamine, serotonin, heparin, leukotrienes, prostaglandins

• avoid allergen
• OTC meds: counteract granules ex: antihistamines. OR interfere with signal ex: zyrtec
• desensitization - allergy shots increase doses over time; creating IgG to block

• cytotoxic response - complement activation
• antibodies - IgG and IgM
• bind to target
• activate complement
• MAC (membrane attack complex) forms and pokes holes in target

• transfusion rxns
• hemolytic disease of the newborns
• thrombocytopenia
• goodpasture syndrome
• myasthenia gravis

• receive wrong blood type
• serum sickness due to many lysed blood cells

• Rh disease
• if mother's immune system "sees" baby's Rh+ blood cells
• she will produce Anti Rh antibodies
• IgG's - cross placenta
• IgG binds the RBC's
• complement activated
• babys RBC lysed
• prevention - give mom RhoGam - Anti Rh Ab's

drug induced

• autoimmune disease
• Ab's target kidney

• auto immune
• Ab's bind to Ach at the NMJ
• loss of muscle function

• immune complex formation
• Ag/Ab complexes
• agglutinate (clump) and precipitate and trigger inflammation

• arthus rxn: at site of Ag introduction or in blood vessels.  ex: vaccination or farmers lung (mold spores, lungs fill w/ fluid)
• rheumatoid arthritis: complexes form in joints; autoimmune
• glomerulonephritis: inflammation due to immune complexes; depositing in kidneys
• systemic lupus (SLE): auto immune; complexes in skin and body organs; butterfly rash and organ lesions

• cell mediated immunity (CMI)
• cellular or delayed type reaction
• takes 24-72 hrs to appear
• ex: contact dermatitis, tuberculin skin test (PPD), poison ivy (uroshiol, hapten)

lack a component in immune response or it's not functioning properly; genetic or viral induced

• bruton's agammaglobulinemia: lack B cells, genetic
• SCID: severe combined immunodeficiency; lack stem cells to produce any WBC; bubble boy; bone marrow transplants; genetic
• AIDS

donated tissue, cells, organs

from self, same MHC's

from genetically identical twin or clone

donor is same species, not genetically identical

donor is another species