Plasma Functionalization of Polycaprolactone Nanofibers Changes Protein Interactions with Cells, Resulting in Increased Cell Viability

The
surface properties of electrospun scaffolds can greatly influence
protein adsorption and, thus, strongly dictate cell–material
interactions. In this study, we aim to investigate possible correlations
between the surface properties of argon, nitrogen, and ammonia and
helium plasma-functionalized polycaprolactone (PCL) nanofibers (NFs)
and their cellular interactions by examining the protein corona patterns
of the plasma-treated NFs as well as the cell membrane proteins involved
in cell proliferation. As a result of the performed plasma treatments,
PCL NFs morphology was preserved, while wettability was improved profoundly
after all treatments because of the incorporation of polar surface
groups. Depending on the discharge gas, different types of groups
are incorporated, which influenced the resultant cell–material
interactions. Argon
plasma-functionalized PCL NFs, only enriched by oxygen-containing
functional groups, were found to show the best cell–material
interactions, followed by N2 and He/NH3 plasma-treated
samples. Sodium dodecyl sulfate polyacrylamide gel electrophoresis
and liquid chromatography–mass spectrometry clearly indicated
an increased protein retention compared with non-treated PCL NFs.
The nine proteins retained best on plasma-treated NF are important
mediators of extracellular matrix interaction, illustrating the importance
thereof for cell proliferation and the viability of cells. Finally,
92 proteins that can be used to differentiate how the different plasma
treatments are clustered and subjected to a gene ontology study, illustrating
the importance of keratinization and extracellular matrix organization.