Covalent Immobilization of P-Selectin Enhances Cell Rolling

@article{citeulike:2236634, abstract = {Abstract: Cell rolling is an important physiological and pathological process that is used to recruit specific cells in the bloodstream to a target tissue. This process may be exploited for biomedical applications to capture and separate specific cell types. One of the most commonly studied proteins that regulate cell rolling is P-selectin. By coating surfaces with this protein, biofunctional surfaces that induce cell rolling can be prepared. Although most immobilization methods have relied on physisorption, chemical immobilization has obvious advantages, including longer functional stability and better control over ligand density and orientation. Here we describe chemical methods to immobilize P-selectin covalently on glass substrates. The chemistry was categorized on the basis of the functional groups on modified glass substrates: amine, aldehyde, and epoxy. The prepared surfaces were first tested in a flow chamber by flowing microspheres functionalized with a cell surface carbohydrate (sialyl Lewis(x)) that binds to P-selectin. Adhesion bonds between P-selectin and sialyl Lewis(x) dissociate readily under shear forces, leading to cell rolling. P-selectin immobilized on the epoxy glass surfaces exhibited enhanced long-term stability of the function and better homogeneity as compared to that for surfaces prepared by other methods and physisorbed controls. The microsphere rolling results were confirmed in vitro with isolated human neutrophils. This work is essential for the future development of devices for isolating specific cell types based on cell rolling, which may be useful for hematologic cancers and certain metastatic cancer cells that are responsive to immobilized selectins.}, address = {Department of Chemical Engineering and Harvard-MIT Division of Health Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, Departments of Chemical Engineering and Biomedical Engineering, University of Rochester, Rochester, New York 14627, and Center for Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, Massachusetts 02139}, author = {Hong, S. and Lee, D. and Zhang, H. and Zhang, J. Q. and Resvick, J. N. and Khademhosseini, A. and King, M. R. and Langer, R. and Karp, J. M. }, citeulike-article-id = {2236634}, doi = {10.1021/la7014397}, journal = {Langmuir}, keywords = {contact\_angle, peg, pegylation, roling}, month = {November}, number = {24}, pages = {12261--12268}, posted-at = {2008-02-05 00:33:48}, priority = {2}, title = {Covalent Immobilization of P-Selectin Enhances Cell Rolling}, url = {http://dx.doi.org/10.1021/la7014397}, volume = {23}, year = {2007} }

TY - JOUR ID - citeulike:2236634 L3 - citeulike-article-id:2236634 TI - Covalent Immobilization of P-Selectin Enhances Cell Rolling JF - Langmuir VL - 23 IS - 24 SP - 12261 EP - 12268 AD - Department of Chemical Engineering and Harvard-MIT Division of Health Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, Departments of Chemical Engineering and Biomedical Engineering, University of Rochester, Rochester, New York 14627, and Center for Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, Massachusetts 02139 N2 - Abstract: Cell rolling is an important physiological and pathological process that is used to recruit specific cells in the bloodstream to a target tissue. This process may be exploited for biomedical applications to capture and separate specific cell types. One of the most commonly studied proteins that regulate cell rolling is P-selectin. By coating surfaces with this protein, biofunctional surfaces that induce cell rolling can be prepared. Although most immobilization methods have relied on physisorption, chemical immobilization has obvious advantages, including longer functional stability and better control over ligand density and orientation. Here we describe chemical methods to immobilize P-selectin covalently on glass substrates. The chemistry was categorized on the basis of the functional groups on modified glass substrates: amine, aldehyde, and epoxy. The prepared surfaces were first tested in a flow chamber by flowing microspheres functionalized with a cell surface carbohydrate (sialyl Lewis(x)) that binds to P-selectin. Adhesion bonds between P-selectin and sialyl Lewis(x) dissociate readily under shear forces, leading to cell rolling. P-selectin immobilized on the epoxy glass surfaces exhibited enhanced long-term stability of the function and better homogeneity as compared to that for surfaces prepared by other methods and physisorbed controls. The microsphere rolling results were confirmed in vitro with isolated human neutrophils. This work is essential for the future development of devices for isolating specific cell types based on cell rolling, which may be useful for hematologic cancers and certain metastatic cancer cells that are responsive to immobilized selectins. KW - contact_angle KW - peg KW - pegylation KW - roling AU - Hong, S AU - Lee, D AU - Zhang, H AU - Zhang, JQ AU - Resvick, JN AU - Khademhosseini, A AU - King, MR AU - Langer, R AU - Karp, JM PY - 2007/11/20/ UR - http://dx.doi.org/10.1021/la7014397 ER -