title: Nanoaggregates of micropurified lipopolysaccharide identified using dynamic light scattering, zeta potential measurement, and TLR4 signaling activity.
abstract: Nanoaggregates composed of selected glycoforms from Escherichia coli 055:B5 lipopolysaccharide (LPS) were prepared by combining sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, zinc-imidazole reverse staining, zinc chelation after cutting gel slices, elution with either 0.5% triethylamine (TEA) or 0.4% to 0.5% surfactant (SDS or deoxycholate [DOC]) from extrusion-generated gel microparticles, and centrifugal diafiltration after appropriate surfactant dilution. Dynamic light scattering allows detecting these aggregates, giving a size distribution from 10 to 100nm in diameter. The formation of the aggregates prepared with selected DOC-eluted LPS glycoforms was notably improved over those prepared with TEA-eluted glycoforms. As the O-side chain length increased in the composition of the former aggregates, there was a gradual decrease in the electrophoretic mobility (from -1.2 to 0.0110(-8)m(2)/Vs), giving a calculated zeta potential from -15 to 0.1mV at pH6.8. These aggregates were further characterized for their abilities to elicit agonistic effects on human Toll-like receptor 4, as shown by in vitro activation of nuclear factor kappa light chain enhancer of activated B cells (NF-κB) in engineered HEK293 cells.
authors.affiliation: Department of Polymers, Institute for Science and Technology of Materials, Havana University, 10400 Havana, Cuba. ehardy@imre.oc.uh.cu
authors.forename: Eugenio
authors.initials: E
authors.lastname: Hardy
authors.forename: Tobias
authors.initials: T
authors.lastname: Kamphuis
authors.forename: Aleksandre
authors.initials: A
authors.lastname: Japaridze
authors.forename: Jan C
authors.initials: JC
authors.lastname: Wilschut
authors.forename: Mathias
authors.initials: M
authors.lastname: Winterhalter
mesh_terms: D003840:Deoxycholic Acid / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism; D005021:Ethylamines / Q000737:chemistry; D057809:HEK293 Cells; D006801:Humans; D008027:Light; D008070:Lipopolysaccharides / Q000032:analysis*; D049329:Nanostructures / Q000737:chemistry*; D012542:Scattering, Radiation; D015398:Signal Transduction; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D051197:Toll-Like Receptor 4 / Q000819:agonists / Q000235:genetics / Q000378:metabolism*
chemical_list: D005021:Ethylamines; D008070:Lipopolysaccharides; D051197:Toll-Like Receptor 4; D003840:Deoxycholic Acid; D012967:Sodium Dodecyl Sulfate; C016162:triethylamine