Engineering cellular response using nanopatterned bulk metallic glass.

Area of Science:

• Biomaterials Science
• Cell Biology
• Nanotechnology

Background:

• Nanopatterning of biomaterials is a key strategy for controlling cell behavior.
• Bulk metallic glasses (BMGs) offer versatile fabrication of nanopatterned surfaces for cell studies.

Purpose of the Study:

• To investigate how different cell types detect and respond to various nanopattern feature sizes on BMG substrates.
• To correlate cellular morphology and responses with substrate nanotopography and underlying biomechanical cues.

Main Methods:

• Fabrication of nanopatterned BMG substrates using thermoplastic forming.
• Culturing and observing fibroblasts, macrophages, and endothelial cells on substrates with varying feature sizes.
• Utilizing nondimensional analysis, molecular pathway analysis, and nanoscale traction force microscopy (FIB-SEM) to characterize cellular responses and biomechanics.

Main Results:

• Fibroblasts detected feature sizes down to 55 nm, decreasing cell area with increasing feature size.
• Macrophages responded to 200 nm features, showing increased size and elongation; they did not respond to 150 nm or smaller.
• Endothelial cells responded to 100 nm features or larger with decreased size and elongation.
• Nanopatterns affected protein adsorption, substrate stiffness, focal adhesion density, and Rho-A GTPase activation, leading to restricted cell spreading and reduced collagen production in fibroblasts.

Conclusions:

• Cellular detection of nanopatterns is cell-type specific and dependent on feature size.
• Substrate nanotopography directly influences cellular biomechanics, cytoskeletal remodeling, and function.
• Nanoscale topography can be engineered to precisely control cellular responses for biomaterial applications.