Conformational regulation of the fibronectin binding and alpha 3beta 1 integrin-mediated adhesive activities of thrombospondin-1.

The recognition of extracellular matrix components can be regulated by conformational changes that alter the activity of cell surface integrins. We now demonstrate that conformational regulation of the matrix glycoprotein thrombospondin-1 (TSP1) can also modulate its binding to an integrin receptor. F18 1G8 is a conformation-sensitive TSP1 antibody that binds weakly to soluble TSP1 in the presence of divalent cations.

Hypergranular promyelocytic leukemia: correlation between morphology and chromosomal translocations including t(15;17) and t(11;17).

The FAB group has reviewed 32 cases of promyelocytic leukemia and variant forms. By utilizing published criteria the ability to make a correct diagnosis by morphology with molecular genetic confirmation and to eliminate cases that did not have the PML/RARalpha rearrangement was excellent.

A preliminary analysis of platelet von Willebrand factor oligosaccharides.

Little is known about the carbohydrate structure of the platelet von Willebrand factor (vWf). We have analyzed N-linked oligosaccharides from both plasma and platelet vWf by Fluorophore-Assisted-Carbohydrate Electrophoresis (FACE) and isoelectric focusing before and after digestion of the proteins with neuraminidase. We observed a greater variety of N-linked oligosaccharides derived from plasma vWf than from platelet vWf.

Glycocalicin levels in the plasma of HIV+ patients: an indicator of platelet turnover.

Glycocalicin (GC) is the carbohydrate-rich portion of platelet membrane glycoprotein Ib(alpha) that can be cleaved from circulating platelets by proteases. The plasma GC level is an indicator of platelet turnover. Using an ELISA for GC, we assayed the plasma of 20 normal children (age 6 to 13 years), 50 HIV+ children (ages 4 to 18 years), 32 normal adults (ages 21 to 53 years), and 50 HIV+ adults (ages 24 to 66 years).