Differential Expression of E‐ and P‐Selectin in the Microvasculature of Sickle Cell Transgenic Mice

Abstract

Objective: There is a growing body of evidence that endothelial cells assume an inflammatory phenotype in sickle cell disease. The authors determined whether (1) the expression of E‐ and P‐selectin differs between sickle cell transgenic (β^S) mice and their wild‐type counterparts, and (2) blood platelets and/or neutrophils contribute to the altered selectin expression. Methods: Expression of E‐ and P‐selectin was measured in different regional vascular beds of wild‐type and β^S mice (with or without thrombocytopenia or neutropenia) using the dual radiolabeled monoclonal antibody technique. Results: Constitutive expression of P‐selectin was significantly increased in the heart, lungs, small bowel, large bowel, and penis of β^S versus WT mice. While thrombocytopenia reduced P‐selectin expression in the small bowel and penis of β^S mice, neutropenia was associated with a reduction in P‐selectin expression only in the penis. E‐selectin expression was not significantly elevated in any vascular bed except the penis of β^S mice. Conclusions: Sickle cell disease promotes an increased P‐selectin expression in several vascular beds. An accumulation of platelets may explain the increased P‐selectin expression observed in some vascular beds.