The effects of surface chemistry and adsorbed proteins on monocyte/macrophage adhesion to chemically modified polystyrene surfaces

Abstract

Monocytes and macrophages play critical roles in inflammatory responses to implanted biomaterials. Monocyte adhesion may lead to macrophage activation and the foreign body response. We report that surface chemistry, preadsorbed proteins, and adhesion time all play important roles during monocyte adhesion in vitro. The surface chemistry of tissue culture polystyrene (TCPS), polystyrene, Primaria, and ultra low attachment (ULA) used for adhesion studies was characterized by electron spectroscopy for chemical analysis. Fibrinogen adsorption measured by (125)I-labeled fibrinogen was the lowest on ULA, higher on TCPS, and the highest on polystyrene or Primaria. Monocyte adhesion on protein preadsorbed surfaces for 2 h or 1 day was measured with a lactate-dehydrogenase method. Monocyte adhesion decreased over time. The ability of preadsorbed proteins to modulate monocyte adhesion was surface dependent. Adhesion was the lowest on ULA, higher and similar on TCPS or polystyrene, and the highest on Primaria. Monocyte adhesion on plasma or fibrinogen adsorbed surfaces correlated positively and linearly to the amount of adsorbed fibrinogen. Preadsorbed fibronectin, immunoglobulin G, plasma, or serum also promoted adhesion compared with albumin preadsorbed or uncoated surfaces. Overall, biomaterial surface chemistry, the type and amount of adsorbed proteins, and adhesion time all affected monocyte adhesion in vitro.

Growth substrate induced functional changes elucidated by FTIR and Raman spectroscopy in in–vitro cultured human keratinocytes

“…Recently it has been demonstrated in the literature that these effects can be expressed in the cell at the level of genomic regulation, thus contributing to very fundamental changes in cellular physiology, ultimately resulting in unknown adjustments to cellular proliferation, motility and, in some cases, phenotype [17][18][19][20][21][22][23]. In this work we have demonstrated that measurements of cellular proliferation and viability on coated spectroscopic substrates can be correlated with spectral changes induced by adjustments to cell physiology when cultured on the different coatings.…”

“…This ultimately results in increasing proliferation and motility, which is also dependent on the charge distribution presented by the ECM coating molecule to the adhering cell [18][19][20][21][22][23]25]. Ultimately the reaction of the cell to such influences are complex, being the cumulative effect of the increased or decreased regulation of a number of stimulatory pathways in the cell, with the end physiological change in any given cell being dependent on the cell and substrate ECM [50,51].…”

“…It has been demonstrated that surfaces and scaffolds for cell culture can induce changes in cellular adhesion and motility [17,18], in their proliferation and differentiation [16,19], and in gene expression [20], ultimately influencing the fate of the cell [21]. Much of the interaction of adherent cells with their culture substrates is dependent on the surface chemistry [18,22] and surface energy [23]. When substrates are coated with biocompatible molecules to effect or enhance cellular proliferation, the conformation of the molecule has also been shown to produce changes in the level of response [19].…”

The effect of phosphorylcholine‐coated materials on the inflammatory response and fibrous capsule formation: In vitro and in vivo observations

“…These changes in conformation expose sequences not normally accessible within the protein that can further interact with other proteins or indeed act as focal attachment points for cellular adhesion. 11 In the in vitro cell adhesion assays described here, various experimental protocols were examined to assess the effect of the presence of serum proteins. The overriding observation from the entire study was that in all assays performed, far fewer inflammatory cells adhered to the PC-coated samples compared with the uncoated controls.…”

Intracellular protein phosphorylation in adherent U937 monocytes mediated by various culture conditions and fibronectin-derived surface ligands

“…For example, monocyte adhesion on a poorly adhesive surface is enhanced by adsorbed IgG [6], while others have shown that fibrinogen is more critical for phagocyte adhesion on biomaterials [7]. Others and we have demonstrated that macrophage adhesion is mainly modulated by the substrate and the extracellular matrix protein such as fibronectin [8,9].…”