Protein adsorption and cell attachment to patterned surfaces.

Area of Science:

• Biomaterials Science
• Cell Biology
• Tissue Engineering

Background:

• Understanding cell attachment to biomaterials is crucial for designing functional tissue architectures.
• Patterned surface chemistry on biomaterials can direct cell behavior.
• The role of specific adhesive proteins in cell localization on patterned surfaces requires elucidation.

Purpose of the Study:

• To investigate the mechanism of human bone-derived cell (HBDC) attachment to surfaces with patterned chemistry.
• To determine the role of serum adhesive glycoproteins in mediating HBDC spatial organization.
• To assess the impact of surface chemistry and protein adsorption on cell morphology and adhesion formation.

Main Methods:

• Photolithography was used to create alternating domains of N-(2-aminoethyl)-3-aminopropyl-trimethoxysilane (EDS) and dimethyldichlorosilane (DMS).
• HBDC were seeded onto patterned surfaces, and their localization was analyzed.
• Serum depleted of adhesive glycoproteins was used to identify mediating proteins.
• Immunostaining confirmed protein adsorption and cell adhesion receptor distribution.

Main Results:

• HBDC preferentially localized to EDS domains within 90 minutes of seeding.
• Vitronectin (Vn) adsorption to EDS domains mediated this spatial organization.
• Fibronectin (Fn) adsorption was inhibited by competing serum components.
• Both Vn and Fn adsorbed to EDS and DMS regions from pure solution, mediating cell adhesion.
• Cell spreading was constrained on EDS domains, with limited integrin receptor clustering and focal adhesion formation.

Conclusions:

• Vitronectin mediates preferential attachment of HBDC to specific patterned surface chemistries.
• The competitive adsorption of serum proteins significantly influences cell localization on biomaterials.
• Constrained cell spreading on certain domains may affect subsequent differentiated cell functions.