Exam 2 Concept Review: Chapter 7 Flashcards
What is Type I Hypersensitivity?
Caused by allergen (can from any type of allergy)
IgEs made for allergen, binds on mast cells leads to chem mediators released
What are the complications of Type I Hypersensitivity?
Anaphylaxis
Hay fever: allergic rhinitis - Nasal mucosa
Food allergies: digestive tract mucosa
Atopic dermatitis/eczema-skin
Asthma- Bronchial mucosa
What is anaphylaxis?
Is a severe, potentially life-threatening allergic reaction. It can occur within seconds or minutes of exposure to something you’re allergic to, such as peanuts or bee stings.
A a systemic reaction
By release of histamine
What does anaphylaxis (anaphylactic shock) cause?
Severe hypoxia: the airways are getting right due to vasodilation around it (it gets smaller from the pressure from the outside pushing it)
Airway obstruction
Decrease blood pressure caused
How does histamine work?
As a result of histamine release, there is vasodilation around it (the blood vessels are getting bigger) so as the pipe gets bigger, the blood pressure lowers
What are the signs and symptoms of Anaphylaxis?
Generalized itching or tingling, especially in the oral cavity
Coughing
Difficulty breathing
Feeling of weakness
Dizziness or fainting
Sense of fear and panic
Edema of eyes, lips, tongue, hands, feet
Hives
Collapse with loss of consciousness
What is anaphylaxis caused by?
Nuts or shellfish
Latex materials
Insect stings
What is the treatment for anaphylaxis?
Requires first aid response: administer EpiPen if available (usually first thing to do) and call 911 (may paramedics can start drug treatment and oxygen)
Treatment in emergency department:
Epinephrine: will vasoconstrict (reduce swelling) and vasodilate the smooth muscle meaning it is going to relax. Vasoconstriction helps bring up blood pressure and elevate the heart beat
Glucocorticoids (steroids)
Antihistamines
Oxygen
Stabilize blood pressure
What are the reasons to intentionally suppress the immune system (immunosuppression)?
Reduction of immune response to prevent rejection: commonly used drugs (cyclosporine, azathiosprine , prednisone)
What are the different types of tissue and organ transplant rejections?
Host vs graft rejection: transplant rejection by recipients immune system
Hyperacute rejection: immediately after transplantation
Acute rejection: develops after several week
Chronic, late rejection: occurs after months or years
What are the risks of immunosuppression?
Risk of infection: opportunistic organism and cancer
What are autoimmune disorders?
Development of antibodies against own cells or tissues
Autoantibodies are antibodies formed against self-antigens - loss of self-intolerance (they know self from non self)
It can affect single organs or tissues or can be generalized
What are the common manifestations of Lupus (SLE)?
Joints: polyarthritis with swollen, painful joints, without damage; arthralgia
Skin: butterfly rash. With erythema on cheeks and over nose or rash on body; photo sensitivity - exacerbation with sun exposure; ulceration sin oral mucosa; hair loss
Kidneys: glomerulonephritis with antigen-antibody deposit in glomerulus, causing inflammation with marked proteinuria and progressive renal damage
Heart: carditis - inflammation of any layer of the heart, commonly pericarditis
What is Lupus (SLE)?
Chronic inflammatory disease-immune complex deposits of antinuclear antibodies (ANA)
Affects primarily women due to inappropriate levels of female hormones
What are antigens and what is it recognized by?
Specific molecules, or parts of molecules body recognizes as foreign and worthy of attack
Recognized by three-dimensional regions called epitopes on antigens
What are classified as antigens?
Proteins of viruses, fungi, and Protozoa
Food(proteins, polysaccharides) and dust
What are the different types of antibodies?
IgG: it is the antibody that cross the placenta and it is the second responder in the body in terms of order on how antibodies respond (Most common in blood)
IgM: first to increase in immune response
IgA: in secretions- tears, colostrum, saliva and mucous membranes (secretions that have the ability to attack pathogens)
IgE: Allergic response (causes the release of histamine and other chemicals. Results in inflammation)
IgD: Attacked to B cells, Activtates B cells
What are B lymphocytes and it’s role in immune response?
Cells that d we develop memory and keep that memory to help with producing antibodies which help the immune system recognize and defend themselves against things it has already been exposed to
What are the different types of T lymphocytes?
Cytotoxic T cells
Helper T cells: facilitate all immune activity
Memory T cells: recognize antigen and stimulate immune response
What is Type II Hypersensitivity (Cytotoxic)?
When antigen is present in cell membrane.
Circulating IgGs react with antigen activating complement system which results in destruction of erythrocytes (hemolysis) by phagocytosis or Cytolytic enzymes
What is Type III Hypersensitivity (Immune Complex)?
Antigen combines with antibody (complexes are stuck somewhere causing destruction)
Forms immune complexes, deposited in tissue
What is Type IV Hypersensitivity (cell-mediated or delayed)
Delayed response by the T lymphocytes
Happens as an inflammatory response
What are the types of acquired immunity?
Natural active: pathogens enter the body and cause illness; antibodies form in host
Ex: person has chickenpox once
Artificial active: vaccine (live or attenuated organisms) is injected into person. No illness results, but antibodies form
Ex: person has measles vaccine and gains immunity
Natural passive: antibodies passed directly from mother to child to provide temporary protection
Ex: placental passage during pregnancy or ingestion of breast milk
Artificial passive: antibodies injected into person (antiserum) to provide temporary
Ex: gamma globulin if recent exposure to microbe
What is the difference between cell-mediated immunity and humoral immunity?
Cell-mediated immunity: lymphocytes are programmed to attack abnormal cells
Humoral immunity: Antibodies are produced
