BEGIN:VCALENDAR VERSION:2.0 PRODID:-//NextToU//EN CALSCALE:GREGORIAN BEGIN:VEVENT UID:69f5fa5b-ceec-4f49-b444-659ee10c84eb@nexttoyou DTSTAMP:20261106T170921Z DTSTART:20261117T181000Z DTEND:20261117T191000Z SUMMARY:Tuning cell-cell interactions through regulation and manipulation of cell surface crowding LOCATION:BRC 280 DESCRIPTION:Future Leaders in Bioengineering Seminar Series\n\nDaniel S.W. Lee\, Ph.D\n\nPostdoctoral Scholar\n\nDepartment of Bioengineering\n\nUn iversity of California\, Berkeley\n\nAbstract\nThe cell surface is the ph ysical vehicle for intercellular interactions\, including immune recognit ion\, cell-cell fusion\, and viral infection. However\, it is also covere d in a dense and diverse population of macromolecules\, including glycosy lated proteins\, lipids\, and even nucleic acids\, that extend well beyon d the membrane at a density of approximately 20\,000 per square micron. T ogether\, these components constitute the glycocalyx\, a nanoscopic polym er brush through which ligands must navigate to bind receptors on the cel l surface. To quantify this energetic barrier\, we developed a molecular sensor for cell surface crowding that inserts into lipid bilayers and act s as a model receptor. We found that surface crowding typically results i n a tenfold increase in dissociation constant for surface binding on a ce ll membrane compared to a lipid-coated bead\, equivalent to a 2-3kBT ener gy penalty per antibody-sized molecule. In this talk\, I will describe ho w we used this crowding sensor to understand how cell surface crowding ac ts as a tunable physical barrier to key physiological cell-cell interacti ons.\n\nFirst\, we interrogated crowding on cells undergoing differentiat ion and found that surface crowding can be developmentally regulated. Dur ing differentiation\, both myoblast and murine thymocyte surfaces become less crow\n\nhttp://next-to-u.app/events/69f5fa5b-ceec-4f49-b444-659ee10c 84eb URL:http://next-to-u.app/events/69f5fa5b-ceec-4f49-b444-659ee10c84eb END:VEVENT END:VCALENDAR