Table 2.

Characteristics of two different ULVWF multimers

	mULVWF multimers	eULVWF multimers
Synthesized in	Megakaryocytes	Endothelial cells
Stored in	α granules of platelets	Weibel-Palade bodies of ECs
Primary distribution at release	In circulation	On the membrane of ECs
Availability	In microcirculation	At ECs following endothelial exocytosis
Exposure to ADAMTS13	As platelet-adherent form	As ECs-adherent form
Interaction with platelets causing	Platelet aggregation and adhesion	Platelet-ULVWF strings
Localization of platelet-ULVWF complexes	Arteriolar and capillary lumens lodged as microthrombi in situ	Endothelial membrane-anchored as microthrombi strings
Example of leading its activity	ADAMTS13 autoantibody	Sepsis-induced endotheliopathy
Endotheliopathic lesion	Microthrombotic microangiopathy	Microthrombotic angiopathy
Hematologic manifestation	Thrombocytopenia and MAHA	Thrombocytopenia and MAHA/aMAHA
Associated inflammation	None to minimal (?)	Mild to severe
Associated clinical syndrome	TTP	TTP-like syndrome

ECs endothelial cells, eULVWF/mULVWF endothelial unusually large von Willebrand factor/megakaryocytic ULVWF, MAHA/aMAHA microangiopathic hemolytic anemia/atypical MAHA, TTP thrombotic thrombocytopenic purpura