       Document 0623
 DOCN  M9650623
 TI    Binding kinetics of an antibody against HIV p24 core protein measured
       with real-time biomolecular interaction analysis suggest a slow
       conformational change in antigen p24.
 DT    9605
 AU    Glaser RW; Hausdorf G; Department of Medical Immunology, Humboldt
       University Berlin,; Medical School (Charite), Germany.
 SO    J Immunol Methods. 1996 Jan 16;189(1):1-14. Unique Identifier : AIDSLINE
       MED/96163539
 AB    The interaction between HIV core protein p24 and the murine monoclonal
       antibody CB-4/1 or its Fab fragment showed unusual kinetics. Recombinant
       p24 was immobilised in a hydrophilic carboxymethyldextran matrix. At
       high concentration of CB-4/1 Fab the association of the antigen-antibody
       complex proceeds in two phases, while dissociation is mono-exponential.
       The antigen has a 'memory', i.e. shortly after dissociation of
       Fab-antigen complex the fast association phase is enhanced. Biphasic
       association was also found in solution. Experiments suggest a reversible
       change of binding properties in the epitope region with an overall time
       constant of about 100 s at room temperature. Intermediate steps with
       faster time constants must be involved. Slow conformational changes of
       p24 seem to be the most probable explanation. A simple model that
       provides a quantitative description of this process could not be found.
       Real-time analysis of antibody binding by surface plasmon resonance is a
       powerful method for studying such changes in the time domain of a few
       seconds to a few minutes.
 DE    Amino Acid Sequence  Antibodies, Monoclonal/CHEMISTRY  *Antibody
       Affinity  Binding Sites, Antibody  Binding, Competitive/IMMUNOLOGY
       Biosensors  Human  HIV Antibodies/*CHEMISTRY  HIV Core Protein
       p24/*CHEMISTRY/*IMMUNOLOGY  Immunoassay  Kinetics  Models, Immunological
       Molecular Sequence Data  Peptides/IMMUNOLOGY/PHARMACOLOGY  Protein
       Conformation  Solutions  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

