Abstract Adhesion of macrophages to material substrates plays an essential role in many biological behaviors and biomedical procedures, including wound healing, cancer treatment and biomaterial implantation. Therefore, altering the adhesion of macrophages using biomaterial design may help control their biological function. In this work, we developed a straightforward method to render the hydrogel surface more hydrophobic and demonstrated that the adhesion of macrophages on hydrogels was enhanced on these more hydrophobic surfaces. Compared to the unmodified methacrylated gellan gum (MGG) hydrogel, the water contact angle increased and the swelling ratio decreased for modified MGG hydrogels. The degree of hydrophobicity was controlled by attaching hydrophobic branches of different lengths to the MGG, while the modification did not change the hydrogel compressive modulus. This ensured that the observed different cell responses were mainly due to hydrophobicity change and not the mechanical property difference among the hydrogels. Cell (RAW 264.7 macrophages) proliferation and spreading increased with increasing surface hydrophobicity. Protein adsorption on hydrogel surfaces showed the same trend. Quantification of adhesion to hydrogel surfaces using a hydrophobic probe showed that adhesion was enhanced as substrate hydrophobicity increased. This suggests that cell adhesion may be promoted due to the increase in hydrophobic adhesion that could enhance protein adsorption. In addition, tumor necrosis factor-α (TNF-α) secretion by lipopolysaccharide (LPS) activated M1 and interleukin-4 (IL-4) activated M2 macrophages was also altered by substrate hydrophobicity. TNF-α production, a marker of pro-inflammatory macrophages, decreased with substrate hydrophobicity. These results suggest that substrate hydrophobic can be used to modulate macrophage responses.
experiencing solvent exchange from good to poor, a gel usually exhibits a monotonous deswelling with time if the good and poor solvents are miscible. [7-11] During this process, the good solvent easily escapes from gels driven by osmotic pressure of solvent-solvent mixing, while the poor solvent hardly enters the gel due to the demixing of polymer and poor solvent (Figure 1a). Here, we report an abnormal swelling of hydrophobic gels in water to form "hydrophobic hydrogels." We discovered that wh...
Last. Guanghui Gao(Changchun University)H-Index: 27
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Abstract Hydrophobic association hydrogels have attracted great attention of many researchers and been widely utilized in tissue engineering stents, drug delivery carriers, wound dressings, and biosensors as intelligent materials due to their excellent mechanical and self-healing properties. Here, we mainly introduced different mechanisms on hydrophobic association hydrogels with high mechanical and excellent self-healing properties. The mechanisms included not only hydrophobic association, but ...
The perspectives of regenerative medicine are still severely hampered by the host response to biomaterial implantation, despite the robustness of technologies that hold the promise to recover the functionality of damaged organs and tissues. In this scenario, the cellular and molecular events that decide on implant success and tissue regeneration are played at the interface between the foreign body and the host inflammation, determined by innate and adaptive immune responses. To avoid adverse eve...
In tissue engineering scaffolds, macrophages play a critical role in determining the host response to implanted biomaterials. Macrophage phenotype is dynamic throughout the host response, and a balance of phenotypes is essential for timely progression from injury to proper wound healing. Therefore, it is important to predict how materials will modulate the response of macrophages. In this study, we investigated the effect of methacrylated gellan gum (GG) hydrogels on macrophage phenotype and pro...
#1David Kosoff(UW: University of Wisconsin-Madison)H-Index: 3
#2Jiaquan Yu(UW: University of Wisconsin-Madison)H-Index: 5
Last. Joshua M. Lang(UW: University of Wisconsin-Madison)H-Index: 17
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Micromilling is an underutilized technique for fabricating microfluidic platforms that is well-suited for the diverse needs of the biologic community. This technique, however, produces culture surfaces that are considerably rougher than in commercially available culture platforms and the hydrophilicity of these surfaces can vary considerably depending on the choice of material. In this study, we evaluated the impact of surface topography and hydrophilicity in milled microfluidic devices on the c...
Vascular smooth muscle cell (VSMC) migration play a key role in the development of intimal hyperplasia and atherosclerosis. Galectin-1 (Gal-1) is a redox-sensitive β-galactoside-binding lectin expressed in VSMCs with intracellular and extracellular localizations. Here we show that VSMCs deficient in Gal-1 (Gal-1-KO) exhibited greater motility than wild type (WT) cells. Likewise, Gal-1-KO-VSMC migration was inhibited by a redox-insensitive but activity-preserved Gal-1 (CSGal-1) in a glycan-depend...
Gellan gum is a naturally occurring polymer that can cross-link in the presence of divalent cations to form biocompatible hydrogels. However, physically cross-linked gellan gum hydrogels lose their stability under physiological conditions, thus restricting the applications of these hydrogels in vivo. To improve the mechanical strength of the gels, we incorporated methacrylate into the gellan gum and chemically cross-linked the hydrogel through three polymerization methods: step growth through th...
This Review gives a brief introduction to hydrogels formed through click chemistry for applications in tissue engineering. Specifically, we focus on three representative click chemistry mechanisms: Diels–Alder reactions, azide–alkyne cycloaddition, and thiol–ene chemistry. Apart from that, we also discuss photoinitiated chain growth polymerization, which also has fast kinetics. The chemical mechanisms of these reactions, along with their advantages and disadvantages, are presented. These gelatio...
Reducing the foreign body response (FBR) to implanted biomaterials will enhance their performance in tissue engineering. Poly(ethylene glycol) (PEG) hydrogels are increasingly popular for this application due to their low cost, ease of use, and the ability to tune their compliance via molecular weight and cross-linking densities. PEG hydrogels can elicit chronic inflammation in vivo, but recent evidence has suggested that extremely hydrophilic, zwitterionic materials and particles can evade the ...
#1Siji Chen(CAU: China Agricultural University)H-Index: 2
Last. Shanshan Tang(CAU: China Agricultural University)H-Index: 2
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Abstract Lignocellulose is the primary component of many biomasses, including corn straw. Herein, lignocellulose in corn straw was disassembled into the individual polymers, cellulose, hemicellulose, and lignin via a mild and facile method. Subsequently, three porous carbon materials were prepared by carbonization and chemical activation of cellulose (PCCC), hemicellulose (PCHC), and lignin (PCLC). The three materials showed higher specific surface areas (2565.7, 2996.1, and 2590.3 m2 g-1) and h...
To reduce the possibility of bacterial infection and implant-related complications, surface modification on polyurethane (PU) film is an ideal solution to endow hydrophobic PU with antibacterial and antifouling properties. In this work, a variety of polyhexamethylene guanidine/ hyaluronic acid (PHMG/HA) multilayer films were self-assembled layer-by-layer on PU films using polyanions, carboxyl-activated HA, and polycations PHMG by controlling the concentration of these polyelectrolytes as well as...