Which of the following statements regarding TNFα are true?
A. TNFα has a marked procoagulant effectB. Passive immunization of patients with neutralizing antibodies to TNFα improves survival from multi-organ system failure
C. TNFα upregulates P-selectin expression
D. The most potent known stimulus for TNFα production and release is IL-1
E. all of above
The Answer
Is.: A. TNFα has a marked procoagulant effect , C. TNFα upregulates P-selectin
expression
Hit points:
ü
TNFα has a marked
procoagulant effect on endothelial cells, precipitating intravascular thrombosis.
ü
TNFα also down
regulates the expression of thrombomodulin, which has the potential to block
the assembly of protein C and protein S complexes, further decreasing the anticoagulant properties of the endothelial cell
surfaces.
ü
TNFα upregulates
a variety of leukocytic adhesion molecules including ICAM-1, PECAM-1, VCAM-I,
F-selectin and P-selectin.
ü
A variety of
exogenous and endogenous factors (including IL-I) are capable of inducing cells
to produce TNFα, however the most potent stimulus for TNFα production and release
is endotoxin.
