Information transfer in mammalian glycan-based communication

Area of Science:

• Immunology
• Cell Biology
• Biochemistry

Background:

• Mammalian cell surfaces utilize glycan-binding proteins (lectins) to decode glycan information, initiating biochemical signaling.
• Analyzing complex glycan-lectin communication pathways is challenging, but single-cell resolution quantitative data can elucidate signaling cascades.

Purpose of the Study:

• To investigate the information transmission capacity of various C-type lectin receptors (CTLs) on immune cells.
• To compare the signaling capabilities of DC-SIGN, MCL, dectin-1, dectin-2, and MINCLE in response to glycan-encoded information.
• To explore the integration of multiple lectin signaling pathways, particularly focusing on dectin-2's modulation by other lectins.

Main Methods:

• Utilized nuclear factor kappa-B-reporter monocytic cell lines expressing specific CTLs (DC-SIGN, MCL, dectin-1, dectin-2, MINCLE), TNFαR, and TLR-1&2.
• Quantitatively assessed and compared the glycan information transmission capacity of these receptors at the single-cell level.
• Investigated the synergistic and integrated signaling effects of co-expressed lectins, including enhancing dectin-2 signaling via co-receptor FcRγ overexpression.

Main Results:

• Most CTLs exhibited similar information transmission capacity, with dectin-2 showing significantly lower efficiency.
• Enhancing dectin-2 pathway sensitivity through FcRγ co-receptor overexpression did not improve its information transmission.
• Signaling pathways involving lectins using similar transduction routes (dectin-1 and dectin-2) showed integrated signaling via compromise.
• Co-expression of MCL synergistically boosted dectin-2 signaling, especially at low glycan concentrations.

Conclusions:

• Dectin-2 demonstrates a distinct, less efficient information transmission capacity compared to other studied CTLs.
• Immune cells integrate glycan information through complex lectin interactions, with co-expressed lectins modulating individual receptor signaling capacity.
• Multivalent interactions involving lectins are crucial for immune cells to accurately translate glycan-encoded information during pathogen recognition.