Linked Life Data

16207051

Source:http://linkedlifedata.com/resource/pubmed/id/16207051

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
21
pubmed:dateCreated
2005-10-6
pubmed:abstractText
A high-throughput microfabricated all-glass microchip, lipid biochip, was created and used to measure fluorescently tagged antibody binding to dinitrophenol (DNP) haptens in planar supported phospholipid/cholesterol lipid bilayers as a function of cholesterol-to-lipid molar ratio (X(CHOL)). Multiple parallel microchannels etched in the lipid biochip allowed simultaneous measurement of antibody binding to hapten-containing and hapten-free lipid bilayers, for a range of aqueous antibody concentrations. Specific and nonspecific antibody binding to the supported lipid bilayers was determined from the internally calibrated intensity of the surface fluorescence using total internal reflectance fluorescence (TIRF) microscopy. The TIRF intensity data of the specific antibody binding were fitted to the Langmuir isotherm and Hill equation models to determine the apparent dissociation constant K(d), the maximum fluorescence parameter F(infinity), and binding cooperativity n. As X(CHOL) increased from 0 to 0.50, K(d) exhibited a minimum of approximately 4 microM and n reached a maximum of approximately 2.2 at X(CHOL) approximately 0.20. However, F(infinity) appeared to be insensitive to the cholesterol content. The nonspecific binding fraction (NS), defined as the ratio of the TIRF intensity for hapten-free bilayers to that with hapten, showed a minimum of approximately 0.08 also at X(CHOL) approximately 0.20. The results suggest that cholesterol regulates the specific binding affinity and cooperativity, as well as suppresses nonspecific binding of aqueous antibody to a planar supported lipid bilayer surface at an optimal cholesterol content of X(CHOL) approximately 0.20. Interestingly, for X(CHOL) approximately 0.40, NS reached a maximum of approximately 0.57, suggesting significant packing defects in the lipid bilayer surface, possibly as a result of lipid domain formation as predicted by the lipid superlattice model. We conclude that cholesterol plays a significant role in regulating both specific and nonspecific antibody/antigen binding events on the lipid bilayer surface and that our lipid biochip represents a new and useful high-resolution microfluidic device for measuring lipid/protein surface binding activities in a parallel and high-throughput fashion.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0743-7463
pubmed:author
pubmed:issnType
Print
pubmed:day
11
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
9666-74
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Cholesterol modulated antibody binding in supported lipid membranes as determined by total internal reflectance microscopy on a microfabricated high-throughput glass chip.
pubmed:affiliation
Department of Physics, Texas Tech University, Lubbock, TX 79409, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't