Thursday, November 8, 2007 - 5:30 PM
629g

Microcontact Printing Of P-Selectin Increases The Rate Of Neutrophil Recruitment Under Shear Flow

Dooyoung Lee, Department of Chemical Engineering, University of Rochester, 217 Goergen Hall, RC 270168, Rochester, NY 14627 and Michael R. King, Department of Biomedical Engineering, University of Rochester, 218 Goergen Hall, RC 270168, Rochester, NY 14642.

P-selectin expressed on the inflamed endothelial surface is a key mediator of the initial steps of inflammation. It has recently been shown that the local variation of endothelial P-selectin expression affects leukocyte recruitment in vivo. Yet, little is known about the dynamics of leukocyte adhesion a patterned P-selectin-surface in vitro. We investigated the influence of microcontact printing of P-selectin on a polystyrene surface in leukocyte recruitment using a parallel-plate flow chamber. Micro-stripe (100 µm × 10 mm) patterns of P-selectin were prepared using a PMDS stamp and isolated human neutrophils perfused over the surface to quantify the level of neutrophil recruitment. We first found a significant increase in cell rolling flux and a decrease in cell rolling velocity on the micropatterned P-selectin surface compared with a randomly adsorbed P-selectin-surface. However, it was determined using immunofluorescent labeling that the number of functional sites of P-selectin transferred by the microcontact printing was less than that by random adsorption. In addition, by using an anti-P-selectin antibody specific for the short consensus repeat domain, the immuno-labeling of the non-functional sites of P-selectin immobilized on a surface was substantially less on the microcontact printed surface. Taken together, these data indicate that the microcontact printing of selectin increases the transfer rate of the adhesion molecule on a surface in the functionally correct orientation and, consequently, improves the recruitment of leukocytes to the selectin surface under flow.