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PubMed · 2153105

Alpha 2 beta 1 integrins from different cell types show different binding specificities.

D Kirchhofer·L R Languino·E Ruoslahti·M D Pierschbacher
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Abstract

Purified alpha 2 beta 1 integrin from human platelets was compared in its function and immunoreactivity to alpha 2 beta 1 from endothelial cells. Both alpha 2 beta 1 integrins bound to type I collagen-Sepharose and had indistinguishable immunoreactivities when analyzed by a panel of monoclonal and polyclonal alpha 2-specific antibodies. However, functional analysis using rechromatography of purified receptors on laminin and collagen-Sepharose showed that endothelial alpha 2 beta 1 was able to bind to laminin, whereas its counterpart from platelets did not. Moreover, a receptor binding assay indicated that, in contrast to platelets, endothelial cells might also use alpha 2 beta 1 to bind to fibronectin. These results suggest that the alpha 2 beta 1 binding specificity may be modulated by cell-type specific factors.

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Binding SitesBlood PlateletsChromatography, AffinityCollagenElectrophoresis, Polyacrylamide GelEndotheliumHumansIntegrinsPrecipitin TestsReceptors, Cell SurfaceReceptors, CollagenUmbilical CordJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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D Kirchhofer, L R Languino, E Ruoslahti, M D Pierschbacher. 1990-01-15. Alpha 2 beta 1 integrins from different cell types show different binding specificities.. https://pubmed.ncbi.nlm.nih.gov/2153105/

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