Lec16 Immunodeficiency Flashcards Preview

Immunology > Lec16 Immunodeficiency > Flashcards

Flashcards in Lec16 Immunodeficiency Deck (33):
1

8 Main Types of Primary immune Defects

- combined defects
- antibody defects
- phagocyte defects
- complement defects
- well-defined systemic defects
- immune dysregulation
- defects of innate immunity
- auto inflammatory defects

2

What is a combined defect?

- Defect in both T and B cells
- usually with lymphoid stem cells

3

What is pneumocystis carinii pneumonia a sign of?

- Common disease in infants with immunodeficiency / serious T cell defects

4

What is typical clinical phenotype of severe combined immunodeficiency?

- onset in first year of life
- serious infections: pneumonia, sepsis, meningitis, viral + fungal infections
- failure to thrive [poor growth]
- diarrhea, skin rashes [thrush]
- many different causes
- have very few lymphocytes

5

What is X linked SCID?

- mutation in x-linked gene for common gamma chain that is used in cytokine receptors
- in IL-2, IL-4, IL-7, IL-9, IL-15, IL-21
- if altered or lacking don't get any of these cytokines
- treatment: get bone marrow transplant
- have no T cells or NK cells, and have B cells that are just not functional

6

What is effect of adenosine deaminase deficiency?

- get no T, B, or BK

7

What is IL-7Ra chainIL7RA mutation?

- get N T and have B and NK deficiency

8

What is recombinase activating gene [RAG] 1/2?

- get no lymphocytes [T or B], do get NK cells

9

What are TRECS?

- T cell receptor excision circles that are created in new T cells as they rearrange their T cell receptor [TCR]
- still persists in cell and get diluted
- can test newborn blood for TRECs to see if have T cells [look for SCID]

10

What is bare lymphocyte syndrome?

- deficiency in MHC II
- still have T cells [unlike in traditional SCID] but have very few CD4 and few gammaglobulins
- autosomal recessive

11

What are common antibody defects?

- XLA
- Hyper IgM

12

What is XLA?

X-linked agammaglobulinemia
- molecular defect Btk [b cell cytoplasmic tyrosine kinase]
- BCR activation signal can't happen

clinical
- affects males
- severe infections in first year of life
- low serum IgG, IgA, IgM, no antibody production
- tiny tonsils [tonsils normally B cells]
- normal lymphocyte numbers but few B cells
- pre-B cells in bone marrow but few mature [plasma cells]
- get chronic sino-pulmonary infections, respiratory failure

treat: life long gamma globulin therapy

13

What disease: 3 year old boy, failure to thrive, pneumonia, low IgA/IgG, normal IgM, normal B/T/etc cells

- low IgG so think XLA but you see normal B cell quantities
- possible: CD40L deficiency so B cells never get info to switch
- basically hyper IgM but without the high IgM

14

What does AID deficiency cause?

- AID = activation induced cytidine deaminase
- deficiency means can't get class switching of antibodies so have just IgM not IgG/IgA/IgE

15

What are common neutrophil defects

- neutropenia = too few neutrophils
- defect in function
--- adhesion
--- locomotion
--- killing
--- abnormal structure

16

What is chronic granulomatous disease?

- defect causes difficulty reducing oxygen
- prevent phagocytosis from occuring
- get granulomata formation: necrotizing granulomas surrounded by neutrophil cell infiltrate, neutrophils come there but can't digest
- x linked or autosomal
- clinical: cervical lymphadenitis, hepatosplenomegaly, eczema

17

What genes cause chronic granulomatous disease?

autosomal
- p47phox, p67phox, p22phox
x-linked
- gp91phox

18

What is wiskott aldrich syndrome

- type of well-defined defect
- x linked recessive disease
- due to auto-inhibited WASP [ a cytoskeletal protein]
- Can't respond to cytokine receptors
- get small platelets that dont work very well
clinical
- petechiae [red dots on skin], eczema, pneumonia, B cell lymphoma,low platelet count, bloody diarrhea

19

what is job's syndrome

- type of well-defined defect
- hyper IgE
- clinical: eczema, skiny boild, pneumonia, lung cyst, cnadida on fingertip, delayed shedding primary teeth

20

What is stat 3?

- imporant in lots of cytokines
- deficiency is autosomal dominant disease
- looks like systemic illness

21

Treatment for severe cellular defect?

- stem cell or bone marrow transplant

22

Treatment for antibody defect?

- immune globulin replacement

23

Cohn-Oncley isolation of IgG

- isolate IgG from blood and put intso solution
-

24

Illnesses associated with B cell/complement

- otitis media
- bronchitis
- bacterial penumonia
- meningitis
- cellulitis

25

illnesses associated with neutrophils

- organ abcesses
- osteomyelitis

26

illnesses associated with T cells

- thrush
- lymphopenia
- herpes zoster
- mycobacteria infection

27

Which genes associated with invasive pneumococcla disease

- IRAK4
- MyD88
- others in toll receptor path

28

What genes associated with warts

CXCR4

29

What genes associated with herpes simplex encephalitis

- toll like receptor 3 and pathway members
- UNC93B
- TRAF3

30

What genes associated with chronic candidiasis

- dectin 1
- card9
- stat1

31

What genes associated with herpes simplex encephalitis

- IL-12
- IL23
- IFN-gamma receptor
- STAT1
macrophage gp91
- IRF8

32

What is effect of IL-2 receptor deficiency?

IL-2 receptor = common gamma chain
deficiency --> x linked SCID

33

Most common immunoglobulin deficiency in population

IgA