STEP1_Immunology Flashcards
(27 cards)
What is graft v. host rejectio/n
Occurs when grafted T-cells proliferate and reject the host cells will foreign proteins (antigens).
What type of rejection occurs immediately after transplant, via anti-donor antibodies?
Hyperacute rejection.
What is an acute rejection?
Cell-mediated reaction via cytotoxic T-cells that react against foreign MHC.
~weeks post-transplant.
What type of rejection occurs months to year post transplant via antibody-mediated vascular damage?
Chronic Rejection
Bruton’s agammaglobulinemia and SCID are what type of immune disease?
B-cell def
Thymic aplasia (DiGeorge) and Chronic Mucocutaneous Candidiasis are what type of immune disease?
T-cell Def
SCID, Wiskott-Aldrich, and Ataxia-Telangiectasia are what type of immune disease?
B and T cell def.
List the common phagocytic def. (6)
- Chronic Granulomatous Disease
- Chediak-Higashi
- Job’s Syndrome
- Leukocyte adhesion def.
- Hyper-IgM syndrome
- IL-12 Receptor def.
Name that disease:
An x‐linked recessive defect in tyrosine kinase gene. results in: ‐
All Ig classes are decreased
‐ ‐
Get recurrent bacterial infections (after 6 months of age)
Only in boys
Bruton’s agammaglobulinemia
Name that disease:
A deficiency of a specific Ig class resulting in defect I isotype switching, results in: ‐
‐ ‐
Sinus infection Lung infections
Most commonly the deficient Ig is IgA
Selective Immunoglobulin Def
Name that disease:
There is a failure of the development in the thymus and parathyroid’s, due to failure of development of the 3rd and 4th pharyngeal pouch, results in: ‐ ‐ ‐
Tetany
Viral and fungal infections (recurrent)
Heart defects
Thymic Aplasia
Name that disease:
This condition leads to a defect in differentiation of the early stem‐cells, results in: ‐ Recurrent infections (viral, bacterial, fungal, and protozoal)
SCID
Name that disease:
Is an x‐linked defect in the ability to mount an IgM response to the capsular polysaccharides of bacteria, results in: ‐
‐ ‐ ‐
Low IgM levels High IgA levels
Normal IgE levels Classic triad of symptoms: Infections, Eczema, and Thrombocytopenic Purpura
WISKOTT-ALDRICH SYNDROME
Name that disease:
A lack of NADPH leads to a defect in neutrophil phagocytosis, results in: ‐
Succeptibility to opportunitic bacterial infections ‐
Diagnosis based on negative nitroblue tetrazolium dye reduction test
(CLASSIC USMLE QUESTION)
CHRONIC GRANULOMATOUS DISEASE
Name that disease:
A defect in microtubular function and lysosomal emptying of the phagocytic cells, results in: ‐
Recurrent pyogenic infections due to staph and strep
CHEDIAK-HIGASHI DISEASE
Name that disease:
T‐cells fail to produce γ‐interferon, thus PMN’s fail to respond, results in: ‐
Eczema, staph abscesses, and elevated IgE
JOB’S SYNDROME
Name that disease:
There is a defect in the LFA‐1 adhesion proteins on the phagocytes, results in severe early life pyogenic infections.
LEUKOCYTE ADHESION DEFICIENCY SYNDROME
Name that disease:
There is a defect in the CD40 ligand on the CD4 Th cells, leading to severe pyogenic infections early in life, results in: ‐ ‐
High IgM levels
Extremely low levels of IgG, IgA, and IgE
HYPER-IgM SYNDROME
What is the Serum Ca+ levels of DiGeorge pt?
HypOcalcemia d/t to hypOparathyroisim
Gonandal dysgenesis is a feature of what congenital syndrome?
Turners
Decrease expression of CD40L == ??
Hyper IgM syndrome;
low levels of IgA, IgE, IgG
What is the presentation of autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) syndrome?
hypoparathyroidism, adrenal insufficiency, chronic mucocutaneous candidiasis, and skin dystrophy
autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) syndrome is d/t to what?
monogenic mutation of AIRE genes (autoimmune regulators); allows escape of self-reactice T-cells from thymus that expend into the periphery and induce autoimmunity.
What does AIRE do?
A specialized population of cells in the thymus called the medullary epithelial cells (MECs), express and present a vast array of autoantigens to maturing T cells. T cells that bind with high affinity to these autoantigens are deleted. The AIRE gene product is a nuclear transcription factor that regulates the expression of autoantigens by MECs in the thymus. Mutations in AIRE allow the escape of self-reactive T cells from the thymus that expand in the periphery and induce autoimmunity.
