Leukocyte Extravasation and Phagocytosis Flashcards
Early activation promotes redistribution of P-selectin from…
Weibel-Palade Bodies (minutes)
L-selectin. Who expresses it? What is its role?
Leukocytes.
Binding to endothelial cells and homing lympho. to LNs
E-selectin. Who expresses it? What is its role?
Endothelial Cells.
Binds Lewis carbohydrates
P-selectin. Who expresses it? What is its role?
Endothelial Cells and platelets.
Early activation of EC by re-distribution of P-selectin from Weibel-Palade bodies.
What do integrins bind to?
he RDG sites of fibronectin and vitronectin
Integrins are composed of….
alpha and beta chains
Different cobinations for families of integrin molecules
beta1 integrins (VLA) are important because…
They mediate the attachment of lymphocytes to the endothelium
beta2 integrins (LFA-a family) are important because…
They mediate the binding of leukocytes to endothelium and function in phagocytosis and antigen presentation
PECAM is expressed on activated….
leukocytes
ICAM and VCAM are ecpressed on ECs activated by…
IL1, TNF
ICAM binds to….
high affinity LFA4 on neutrophils
VCAM binds to…
VLA integrins on monocytes and lymphocytes
What is LAD1
A leukocyte deficience in which there is a defect in beta1 integrins
What is LAD2?
Lack of sialyl Lewis X glycoproteins (the ligand for selectins)
Killing and degradation is accomplished most by…
oxygen dependent processes
i.e. production of reactive oxygen intermediates, myloperoxidase
