Modulating cell response on cellulose surfaces; tunable attachment and scaffold mechanics.

Area of Science:

• Biomaterials Science
• Surface Chemistry
• Cell Biology

Background:

• Cell attachment and morphology are crucial for biomaterial performance.
• Current methods often rely on protein modifiers or ligands for cell adhesion.
• Developing cell-instructive biomaterials without exogenous agents is a significant challenge.

Purpose of the Study:

• To chemically modify cellulose surfaces to promote direct mammalian cell attachment.
• To investigate the influence of surface charge and scaffold stiffness on cell behavior.
• To create novel functionalized cellulose biomaterials for cell support and morphology regulation.

Main Methods:

• Cellulose surface modification via reaction with glycidyltrimethylammonium chloride (GTMAC) to introduce trimethylammonium groups.
• Quantification of surface charge using ζ-potential and electric force microscopy.
• Modulation of cellulose film stiffness through glyoxal crosslinking and measurement via atomic force microscopy.
• Assessment of MG-63 cell attachment and morphology on modified cellulose scaffolds.

Main Results:

• A low degree of substitution (1.4%) of cationic groups on cellulose significantly increased MG-63 cell attachment (>90%).
• Cell attachment plateaued at higher degrees of substitution (ca. 1.85%), correlating with surface charge.
• Cell morphology could be effectively regulated by tuning scaffold stiffness (76-448 kPa) via crosslinking.
• Direct cell attachment and morphology control were achieved without protein modifiers.

Conclusions:

• Tailored cationic cellulose biomaterials can be synthesized through surface functionalization and crosslinking.
• These materials promote direct mammalian cell attachment and allow for tunable control over cell morphology.
• This approach represents a significant advancement towards cell-instructive biomaterials for implantation, utilizing only scaffold and cell interactions.