Vascular PG-M/versican variants promote platelet adhesion at low shear rates and cooperate with collagens to induce aggregation.

We have identified a novel von Willebrand factor/fibrinogen/selectin-independent, platelet adhesion-promoting function of vascular PG-M/versicans that may be relevant in normal venous thrombosis and critical in atherosclerotic conditions. A purification scheme was devised to obtain vascular versicans, which by biochemical, immunochemical, and ultrastructural means were asserted to be 1) composed primarily of isoforms V1 and V2; 2) free of contaminants; 3) prevalently substituted with chondroitin-4-sulfate and dermatan sulfate (DS) chains; and 4) capable of binding hyaluronan to form link protein-stabilized ternary complexes. Real-time analysis of human platelet perfused under diverse shear forces showed that they largely failed to bind to several vascular and nonvascular proteoglycans (PGs).

Improving fluorescence-based assays for the in vitro analysis of cell adhesion and migration.

Cell adhesion and cell migration are two primary cellular phenomena to be approached in vitro in order to allow for the effective dissection of the individual events and the unravelling of their underlying molecular mechanisms. The use of assays dedicated to the analysis of cell adhesion and migration in vitro also affords an efficient way of conducting larger basic and applied research screenings of the conditions affecting these processes and are potentially exploitable in the context of routine tests in the biological and medical fields. Therefore, there is a substantial interest in devicing more rationale such assays and major contributions in this direction have been provided by the advent of procedures based on fluorescent cell tagging.