Lecture 14 Flashcards Preview

Mbio 1220 > Lecture 14 > Flashcards

Flashcards in Lecture 14 Deck (32):
1

Hypersensitivity also referred to as an...

allergy

2

Hypersensitivity

antigenic response beyond that considered normal. immune response is mounted against an allergen (the allergen is that antigen that causes hypersensitivity)

3

Hypersensitivity type 1 is referred to as

anaphylactic response

4

Type 1 hypersensitivity; 1st encounter with allergen..

causes B cells to differentiate into plasma and memory cells, the plasma cells make IgE which binds to mast cells or basophils (no symptoms)

5

Type 1 hypersensitivity; 2nd encounter with allergen...

IgE molecules bind to antigen and mast cell/basophil releases histamine

6

Histamine triggers

-vasodilation, redness, swelling itchiness
-mucous production
-contraction of bronchial muscles

7

If allergen is spread throughout the body..

sudden decrease in blood pressure (anaphylactic shock)

8

3 treatments to type 1 hypersensitivity

-antihistamine
-epinephrine
-allergy shots

9

Antihistamine

blocks the action of histamine, its still produced but cannot trigger inflammation (best for mild symptoms)

10

Epinephrine

used to treat anaphylactic shock. acts as vasoconstrictor increasing blood pressure, lasts for 20 min that buys time to allow for admin of intravenous antihistamine

11

Allergy shot

injected like vaccine, increasing doses of antigen are given over 2 years. induces memory cells that produce IgG not IgE. IgG will bind to and neutralize the antigen preventing it from binding to IgE (no histamine release)

12

Type 2 hypersensitivity

antibody dependent cytotoxicity, antibodies are produced by foreign human cells

13

Type 2 hypersensitivity blood transfusion

ABO blood group system, antibodies target A and B antigens on red blood cells. activates macrophages leading to phagocytosis and complement activation against foreign cells

14

Type 2 hypersensitivity Rh factor

only occurs on 2nd or subsequent pregnancy. Rh is another surface antigen on red blood cells. hemolytic disease of newborn can result. child produced between Rh- woman and Rh+ man. Child has 50% of being Rh+ If occurred, mother makes antibodies again Rh+ blood cells which can kill baby after birth

15

Type 3 hypersensitivity

immune complex formation, occurs when there are certain antibody to antigen ratios in the blood. antibody forms small complexes w. the antigen which get trapped in membrane causing probs

16

Type 3 hypersensitivity can also..

activate complement which in turn activates neutrophils to release enzymes. causes inflammation and damage to blood vessels

17

Type 4 hypersensitivity

delayed hypersensitivity, result of a cell mediated response. causes delayed reaction 1-3 days after contact. results in activation of memory T cells

18

How does type 4 hypersensitivity happen

-small chemicals interact with the skin proteins to form antigen
-causes change in skill cells
-cell mediated immune response acts against foregone or abnormal cells

19

Hype 4 hypersensitivity example

poison ivy. first contact limited response occurs and there is no resulting dermatitis (memory T cells produced) second contact memory T cells differentiate into activated cytotoxic T cells

20

Transplantation

involved cells mediated response against antigenic ally different MHC molecules.

21

Successful transplants require

-closely matched tissues
-treatments; drugs that suppress the immune system
-since immune system is suppressed transplant patients are very susceptible to infection

22

Cyclosporin

prevents clonal expansion of T cells (for transplant)

23

Graft vs. host disease

cytotoxic T cells from the donor tissue see the host's body as foregone and attack. often occurs after bone marrow transplant

24

2 immunodeficiency disorders

-primary (congenital) immunodeficiency
-acquired immune deficiency

25

Primary congenital immunodeficiency

ex: severe combined immunodeficiency disease (SCID). non functional T and B cells. allows severe infection to develop

26

Acquired immune deficiency

ex: acquired immunodeficiency syndrome (AIDS) last stage in HIV, kills all T helper, macrophages, dendritic cells. patient in extremely susceptible to infection

27

Autoimmune disease

body mounts an immune response against itself. can occur in response to infection, can be genetic, or unknown

28

4 types of autoimmune disease

-rheumatic fever
-rheumatoid arthritis
-lupus
-multiple sclerosis

29

Rheumatic fever

develops in some people following strep throat, antibodies are produced against streptococcus M protein (very similar to heart muscle protein, so cause attack of heart tissue)

30

Rheumatoid arthritis

IgM, IgG, and complement act against collagen in the joints. causes chronic inflammation and joint pain

31

Lupus

antibodies produced to chromatin which is a complex of protein, DNA and RNA. chromatin-antibody complexes accumulate in the joints, kidneys, and blood vessels

32

Multiple sclerosis

T cells and macrophages attack the myelin sheath covering neurons. Symptoms range from mild father to severe paralysis. (may be triggered by infection w/ epistein barr virus