Lecture 11 - Autoimmunity In Hematology Flashcards
1
Q
Positive protective immune response
A
- immunity
2
Q
Negative protective immune response
A
- self tolerance
3
Q
Defective positive immune response
A
- autoimmunity
- allergy
4
Q
- negative defective immune response
A
- immunodeficiency
- infection - malignancy
5
Q
Paroxysmal cold haemoglobinuria
A
- first described autoimmune disease
- something coats RBC and results in their lysis
- called “erythrocytes coating factors”
- ANA: antinuclear factors
6
Q
Self/non self discrimination
A
- during development in primary lymphoid tissue
- T and B lymphocytes learn to discriminate between self and foreign antigens
7
Q
Self tolerance two signal hypothesis
A
- in embryo: clonal deletion of T cell that bind to self molecules
- but also occurs later: need two signals: an antigen and a costimulatory signal
8
Q
Stimulate CD28
A
- goes from anergy to activation and prloferation
9
Q
Block B7
A
- goes from activation and proliferation to anergy
10
Q
Autoimmunity
A
- precipitated by interaction of environment with genetic susceptibility: infection, drug
- transient responses can occur after inflammation but only persist if genetic susceptibility
11
Q
Common features of autoimmune disease
A
- genetic predisposition
- female preponderance
- chronic fluctuating course
- lymphoid infiltrate in tissues
- presence of autoantibodies
- response to immunosuppression
12
Q
Autoimmune hemolytic anemia
A
- antibodies to components of the erythrocyte membrane
- may be detected +/- complement -> hemolysis
- generally treatment is by immunosuppression
13
Q
Type II cytotoxic reaction
A
Ab binds to RBC -> activation of complement pathway -> MAC complex punches whole in cell-> lysis
14
Q
Immune thrombocytopenia
A
- decrease in platelet numbers -> petecchia
15
Q
Causes of thrombocytopenia: isolated/incidental
A
- immune
- gestational
- occult liver disease
- myelodysplastic syndrome
- congenital
- HIV infection
