Proteomic Analysis of Mesenchymal Stem Cells and Monocyte Co-Cultures Exposed to a Bioactive Silica-Based Sol-Gel Coating

New methodologiescapable of extensively analyzing thecell-materialinteractions are necessary to improve current in vitro characterizationmethods, and proteomics is a viable alternative. Also, many studiesare focused on monocultures, even though co-cultures model betterthe natural tissue. For instance, human mesenchymal stem cells (MSCs)modulate immune responses and promote bone repair through interactionwith other cell types. Here, label-free liquid chromatography tandemmass spectroscopy proteomic methods were applied for the first timeto characterize HUCPV (MSC) and CD14(+) monocytes co-culturesexposed to a bioactive sol-gel coating (MT). PANTHER, DAVID,and STRING were employed for data integration. Fluorescence microscopy,enzyme-linked immunosorbent assay, and ALP activity were measuredfor further characterization. Regarding the HUCPV response, MT mainlyaffected cell adhesion by decreasing integrins, RHOC, and CAD13 expression.In contrast, MT augmented CD14(+) cell areas and integrins,Rho family GTPases, actins, myosins, and 14-3-3 expression. Also,anti-inflammatory (APOE, LEG9, LEG3, and LEG1) and antioxidant (peroxiredoxins,GSTO1, GPX1, GSHR, CATA, and SODM) proteins were overexpressed. Onco-cultures, collagens (CO5A1, CO3A1, CO6A1, CO6A2, CO1A2, CO1A1,and CO6A3), cell adhesion, and pro-inflammatory proteins were downregulated.Thus, cell adhesion appears to be mainly regulated by the material,while inflammation is impacted by both cellular cross-talk and thematerial. Altogether, we conclude that applied proteomic approachesshow its potential in biomaterial characterization, even in complexsystems.

Automated summary

New methodologies, such as proteomics, are necessary to improve in vitro characterization methods and better model natural tissues by analyzing cell-material interactions. In this study, label-free liquid chromatography tandem mass spectrometry proteomic methods were used to characterize the effects of a bioactive sol-gel coating on co-cultured human mesenchymal stem cells (MSCs) and CD14(+) monocytes. The results showed that the material mainly affected cell adhesion, while both cellular cross-talk and the material impacted inflammation.