Spatial presentation of biological molecules to cells by localized diffusive transfer

Area of Science:

• Cell Biology
• Biotechnology
• Tissue Engineering

Background:

• Cellular decisions rely on spatially localized soluble signals in tissues.
• Existing in vitro methods for recapitulating these signals face limitations like introduced variables (e.g., fluid flow) and restricted patterning capabilities.
• A need exists for adaptable methods to precisely control soluble factor presentation in standard cell culture settings.

Purpose of the Study:

• To develop an adaptable method for spatial presentation of biomolecules in traditional open cell cultures.
• To enable user-defined patterning of diverse solutes with control over geometry and exposure dynamics.
• To overcome limitations of current microscale strategies for recapitulating in vivo soluble factor gradients.

Main Methods:

• Developed adaptable device inserts for standard culture wells to facilitate localized diffusive pattern transmission.
• Utilized microscale spaces between device features and adherent cells for pattern transmission.
• Employed finite element modeling to investigate pattern fidelity, device geometry, and diffusion kinetics.
• Applied the method for spatial control of cell labeling, reporter cell heterogeneity, and viral particle patterning.

Main Results:

• Demonstrated spatial control of cell labeling with pattern features from hundreds of microns to millimeters.
• Achieved sequential application of multiple patterns and sustained exposure to small molecule modulators.
• Successfully patterned larger, slowly diffusing particles including adenoviral, lentiviral, and Zika virus particles.
• Confirmed method's adaptability across diverse diffusible factors, geometries, exposure dynamics, and cell types.

Conclusions:

• The developed method provides a versatile platform for spatial patterning of biomolecules in standard in vitro cultures.
• This technique overcomes limitations of existing methods, offering precise control over soluble factor presentation.
• The approach is well-suited for broad adoption across various biological research fields, including studies of development, disease, and gene delivery.