Inflammation Flashcards
Hypersegmented neutrophils (> 5 segments) are thought to be pathognomonic of what class of anemias?
megaloblastic anemias (vit B12 or folate deficiencies)
What is the difference between selectins and integrins?
selectins: weak binding; initiate rolling
integrins: stable binding and adhesion
Lactoferrins purpose in secondary granules of PMNs?
to chelate iron
What are the steps in neutrophil margination and adhesion?
Step 1: the endothelial cells at sites of inflammation have increased expression of E- selectin and P selectin, due to elaboration of cytokines by resident tissue macrophages
Step 2: neutrophils weakly bind to the endothelial selectins and roll along the surface
Step 3: neutrophils are stimulated by chemokine to express their integrins
Step 4: binding of the integrins to cellular adhesion molecules (ICAM-1 and VCAM-1) allows the neutrophils to firmly adhere to the endothelial cell.
Name some endothelial selectins.
P-selectin
E-selectin
GlyCam-1/ CD34
Name some endothelial integrins.
ICAM-1
VCAM-1
Name some leukocyte selectins?
Sialyl-Lewis X & PSGL -1 (bind to P and E selectins)
L-selectin (binds to GlyCam-1 CD-34)
What are some leukocyte integrins?
LFA-1 & MAC-1 (with ICAM-1)
VLA-4 (with VCAM-1)
What are some conditions in which defects of adhesion can be seen?
DM
corticosteroid use
acute alchohol intoxication
Leukocyte adhesion deficiency Type 1
Defects in phagocytosis and degranulation of neutrophils can be seen in what condition?
Chediak-Higashi
Is Chediak Higashi an AR or AD condition?
AR
LAD type 1 (leukocyte adhesion deficiency type 1) is due to a defiency of what?
defiency of B2 integrin subunit (CD18) responsible for synthesis of LFA1
LAD type 1 is an AR or AD condition?
AR
What are characteristic features when one has LAD Type 1 that can be evidenced?
- recurrent bacterial infection (non pyogenic)
- delay in umbilical cord sloughing
Be able to draw out the O2 dependent killing involved. in a phagocyte vacuole.
Describe oxygen dependent intracellular killing.
- respiratory burst require O2 and NADPH oxidase and produces superoxide (O2-) hydroxyl radicals (OH) and hydrogen peroxide (H2O2)
- myeloperoxidase require H2O2 and halide (Cl-) and produces HOCl (hypochlorous acid)
What does Oxygen-independent killing involve. (What enzymes/substances etc.)?
lysozyme, lactoferrin, acid hydrolases, bactericidal permeability increasing protein (BPI), and defensins
What are some conditions that are caused by deficiency in O2 dependent killing? Explain.
Chronic granulomatous disease of childhood
marked by deficiency of NADPH oxidase, lack of superoxide and hydrogen peroxide
myeloperoxidase deficiency
Inheritance pattern of CGD of childhood?
can be X-linked or autosomal recessive
What will the nitro blue tetrazolium test be in a patient with myeloperoxidase deficiency?
positive (purple blue)
Inheritance pattern of myeloperoxidase defiency?
AR