(8-20) Immune Disorders: Hypersensitivities Flashcards
1. Define: Hypersensitivity, Allergy, Autoimmune, Immunodeficiency 2. Describe the immunologic reactions involved defense against helminthes. 3. Describe the immunologic reactions involved in type I hypersensitivities. 4. Give an example of localized type I hypersensitivities. 5. Define: Wheal, Flare 6. Give an example of widespread type I hypersensitivities. 7. Define: Anaphylaxis, Anaphylactic shock 8. Describe the immunologic reactions involved in type II hypersensitivities and contras (30 cards)
How many types of hypersensitivities are important in microbiology?
Four
What are the 3 possible disorders of the immune system?
- Hypersensitivities (allergies)
- Autoimmunity
- Immunodeficiency
What is the immune response that causes tissue injury?
Hypersensitivity (allergy)
What causes a response against self-antigens?
Autoimmunity
What causes a lack of immunological response?
Immunodeficiency
Which type of hypersensitivity involves an immediate response and is IgE-mediated.
Type I
Which type of hypersensitivity is cytotoxic?
Type II
Which type of hypersensitivity is immune complex (Ab/Ag)-mediated?
Type III
Which type of hypersensitivity is delayed cell-mediated?
Type IV
Anaphylactic shock is an example of which type of hypersensitivity?
Type I
Blood transfusion reactions are an example of which type of hypersensitivity?
Type II
Disseminated intravascular coagulation in Gram-negative septicemia is an example of which type of hypersensitivity?
Type III
Tuberculin reaction is an example of which type of hypersensitivity?
Type IV
Can large parasites within the gut (ex. helminthes) be phagocytosed? Why or why not?
No. When a parasite is larger than a phagocytic cell it is physically impossible for phagocytosis to occur.
How are large parasites within the gut dealt with?
- Antigen from helminthes penetrates mucosa and binds (two or more) IgE on mast cells
- Mast Cells produce inflammation of the mucosal surface
- Leads to the “outflow” of antibody, complement, effectors cells of ADCC (NK cells and eosinophils)
- Eosinophils produce toxic proteins against helminthes
How do Mast Cells produce inflammation?
- Mast cells have IgE antibodies on their surface.
2. IgE releases pro-inflammatory compounds (e.g., histamine) when antigen is bound
What is the name given for IgE-mediated reaction? What type of reaction is it?
- Anaphylaxis
2. Type I Hypersensitivity
When is anaphylaxis an appropriate response?
During a helminth infection.
What is Hay Fever?
Mast cell degranulation in the respiratory mucosa, due to IgE antibodies (on mast cells) against pollen grains. (Type I)
What is another word for Wheal and Flare skin reaction, and what is a common cause?
Hives, caused by a Type I hypersensitivity to Lobster.
If a sensitized-to antigen (IgE is on mast cells) gets widely disseminated through the entire body (via the blood), the widespread mast cell/basophil degranulation will lead to which 4 events? What is this called?
Anaphylactic Shock
1. Inflammation ~ Blood vessel dilation of ALL vessels 2. Rapid drop in blood pressure 3. Lack of blood (oxygen) delivered to critical tissue 4. Death
Peanuts, bee stings, and penicillin are antigens that tend to result in what?
Anaphylactic Shock, a Type I Hypersensitivity
What is the treatment for anaphylactic shock?
A shot of adrenalin (epinephrine)
Complement-binding antibodies bind to the surface of cells, leading to destruction or ADCC in which type of sensitivity?
Type II
