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Antigenic Liposomes for Generation of Disease-specific Antibodies
Published on: October 25, 2018
Contact-dependent, immunecomplex-mediated lysis of hapten-sensitized liposomes
B Babbitt1, L Burtis, P Dentinger
1LipoGen, Inc., Knoxville, Tennessee 37932.
Bioconjugate Chemistry
|May 1, 1993
Summary
New contact-sensitive liposomes, made with dioleoylphosphatidylethanolamine (DOPE), aggregate and lyse upon specific antibody binding. This liposome destabilization is temperature-dependent and shows potential for immunodiagnostic assays.
Area of Science:
- Liposome technology
- Immunosensors
- Biophysical chemistry
Background:
- Liposomes are versatile drug delivery systems.
- Developing liposomes with specific triggers for destabilization is crucial for targeted applications.
- Contact-sensitive liposomes offer a novel approach to triggered liposome release.
Purpose of the Study:
- To characterize a new class of stable, contact-sensitive liposomes.
- To investigate the mechanism of liposome aggregation and lysis induced by antibodies.
- To explore the potential of these liposomes in immunodiagnostic assays.
Main Methods:
- Formulation of large unilamellar liposomes using dioleoylphosphatidylethanolamine (DOPE) and a haptenated lipid.
- Stability assessment in isotonic buffer at 4°C.
- Induction of aggregation and lysis using bivalent anti-hapten antibodies.
- Thermostability testing and effect of antibody concentration.
- Demonstration of immunodiagnostic potential using theophylline-haptens.
Main Results:
- Liposomes exhibited remarkable stability for over 6 months at 4°C.
- Specific bivalent antibody binding induced rapid liposome aggregation and lysis.
- Lysis was immunospecific and dependent on antibody valency.
- Aggregation preceded lysis, and lysis was accelerated at higher temperatures (70-80°C).
- Theophylline-haptens demonstrated dose-dependent inhibition of antibody-induced lysis.
Conclusions:
- Contact-sensitive liposomes are a stable and specifically triggered liposome system.
- Liposome aggregation is a prerequisite for antibody-induced lysis.
- These liposomes show promise for homogeneous immunodiagnostic assays, such as for theophylline detection.
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