Detection of low-density cell-surface molecules using biotinylated fluorescent microspheres

Area of Science:

• Biotechnology
• Immunology
• Cell Biology

Background:

• Cell surface antigens and receptors are crucial for cellular function and communication.
• Accurate detection methods are needed to analyze heterogeneous cell populations.
• Existing methods may lack the sensitivity to detect low-abundance surface markers.

Purpose of the Study:

• To develop a sensitive reagent for studying cell surface antigens and receptors.
• To enable the analysis and potential manipulation of cells based on surface marker expression.
• To establish a method for detecting cells with low numbers of surface complexes.

Main Methods:

• Development of biotinylated fluorescent microspheres.
• Crosslinking microspheres via streptavidin to biotinylated antibodies or ligands.
• Labeling of target antigens or receptors on cells.
• Detection of labeled cells using flow microfluorimetry.

Main Results:

• Demonstrated highly sensitive detection of cell surface antigens and receptors.
• Established that cells with fewer than 200 surface antigen-antibody complexes per cell are detectable.
• Successfully labeled and detected hybridoma cells expressing antigen-specific surface immunoglobulin using a biotinylated peptide immunogen.

Conclusions:

• Biotinylated fluorescent microspheres offer a sensitive tool for cell surface marker analysis.
• This technique facilitates the study of heterogeneous cell populations and low-abundance markers.
• The method is applicable to detecting specific cell types, such as hybridomas, based on their surface immunoglobulin.