Physical extraction of antigen and information

Area of Science:

• Cell biology
• Immunology
• Biophysics

Background:

• Cells use surface receptors to sense environmental cues for adaptation.
• Biochemical signaling within cells is well-studied, but physical processes during cell-cell contact are less understood.
• Immune B cells in germinal centers (GCs) are crucial for adaptive immunity.

Purpose of the Study:

• To investigate the impact of physical processes during cell-cell contact on cellular signal acquisition.
• To explain the phenotypic transition of naive to GC B cells through a physical information extraction framework.
• To propose that physical information acquisition enhances adaptive evolution.

Main Methods:

• Developed a theory of stochastic antigen transfer.
• Modeled physical antigen extraction by B cells.
• Analyzed the interplay between receptor signaling, force usage, and contact architecture.

Main Results:

• Physical extraction of antigen clusters by B cells precedes internalization and offers adaptive benefits.
• Maximizing information gain via physical extraction explains the transition to GC B cell phenotype.
• Binding-lifetime measurement and physical extraction act as complementary antigen recognition modes, extending dynamic range.
• Optimal receptor cluster size decreases with improved affinity, consistent with GC B cell multifocal synaptic patterns.

Conclusions:

• Physical information extraction is a key mechanism for cellular adaptation and immune response.
• Combining physical extraction with binding-lifetime measurement significantly enhances affinity discrimination.
• The physical-information framework provides insights into B cell evolution and function.
• Cells may physically enhance information acquisition to sustain adaptive evolution.