Platelet-Endothelial Cell Interactions Following Freeze-Thaw Injury or Detergent Treatment to Cultured Cells In Vitro.

摘要

Platelet interactions with cultured bovine endothelial cells were studied following freeze-thaw damage or detergent treatment. Platelets from whole blood (WB), platelet rich plasma (PRP) or gel filtered (GFP) did not interact directly with freeze-thaw damage endothelial cells. Freezing and thawing did result in the exposure of an extracellular matrix (ECM) located beneath the cells, which proved very thrombogenic. Platelets from all sources attached to both microfilament and amorphous components of the ECM, although only platelets from WB demonstrated aggregation and extensive pseudopodia formation. Treatment of cells with Triton-X detergent resulted in exposure of a intracellular cytoskeleton. Most platelets attached to the cytoskeleton were located near the cell border and had one or more pseudopodia either in contact with extracellular material or penetrating the cytoskeleton. Adhesion of platelets to ECM may represent platelet-collagen or platelet-fibronectin interactions since both are produced by and incorporated into the ECM. Platelet interaction with endothelial cytoskeletons probably represented pseudopodia contact with the now exposed ECM located beneath the endothelial cells. The possibility that platelets also adhered to intracellular components could not be eliminated. These findings are in agreement with data from an isolated aorta freeze-thaw injury model.