Accessing and Assessing the Cell-Surface Glycocalyx Using DNA Origami.

Area of Science:

• Biotechnology
• Nanotechnology
• Cell Biology

Background:

• The cell-surface glycocalyx acts as a barrier, but its functional properties are poorly understood.
• Current methods for characterizing the glycocalyx are primarily morphological, not functional.

Purpose of the Study:

• To demonstrate direct anchoring of DNA origami nanotiles to the glycocalyx.
• To functionally assess the glycocalyx barrier using DNA nanotiles.
• To compare glycocalyx anchoring with traditional phospholipid bilayer anchoring.

Main Methods:

• Anchoring DNA origami nanotiles to single-stranded DNA initiators on the cell surface.
• Comparing accessibility to glycocalyx-anchored vs. phospholipid bilayer-anchored nanotiles.
• Utilizing enzymatic degradation (trypsin, neuraminidase) to probe glycocalyx integrity.

Main Results:

• DNA nanotiles successfully accessed glycocalyx-anchored initiators.
• Access to the underlying phospholipid bilayer was restricted by the glycocalyx.
• Guanine-rich sequences in DNA origami nanotiles were expelled by the glycocalyx.
• Glycocalyx integrity correlated with cell-to-cell accessibility.
• Glycocalyx anchoring enhanced nanotile stability and cellular uptake compared to phospholipid bilayer anchoring.

Conclusions:

• DNA origami nanotiles provide a functional readout of glycocalyx barrier properties.
• The glycocalyx barrier effectively regulates molecular accessibility and influences cell-cell interactions.
• Glycocalyx anchoring of nanodevices offers advantages for cell-surface applications.