Label-free characterization of cell adhesion using reflectometric interference spectroscopy (RIfS)

Area of Science:

• Biophysics
• Immunology
• Cell Biology

Background:

• Cell adhesion and T cell interactions are vital for immune responses and inflammation.
• Current methods for studying these interactions can be complex or require labels.

Purpose of the Study:

• To demonstrate the utility of Reflectometric Interference Spectroscopy (RIfS) for detecting cell adhesion.
• To analyze T cell interactions with functionalized surfaces in a flow system.
• To investigate activation-dependent cell spreading and signaling.

Main Methods:

• Utilized RIfS, a label-free, time-resolved optical technique.
• Immobilized monoclonal antibodies on a transducer surface to capture T cells.
• Studied Jurkat T cells, a derivative lacking Lck, and cells treated with cytochalasin D.
• Functionalized surfaces with antibodies against TCR/CD3 and CD28.

Main Results:

• RIfS successfully detected the adhesion of Jurkat T cells to antibody-functionalized surfaces.
• Observed activation-dependent cell spreading following initial attachment.
• RIfS curves varied based on cell type, signaling inhibition (Lck-deficient cells), and actin polymerization inhibition (cytochalasin D).
• Differences in RIfS curves indicated distinct adhesion and spreading dynamics.

Conclusions:

• RIfS is a viable label-free method for real-time analysis of cell adhesion and activation.
• The technique can differentiate between cells with varying signaling capacities and responses.
• RIfS offers a powerful tool for studying cell-surface interactions in immunology and cell biology.