Preparation of a small intestinal submucosa modified polypropylene hybrid mesh via a mussel-inspired polydopamine coating for pelvic reconstruction

Zwitterion mediated anti-protein adsorption on polypropylene mesh to reduce inflammation for efficient hernia repair

The effectiveness of polypropylene (PP) mesh is often compromised by severe inflammation. Engineering anti-inflammatory coatings has significant implications for PP mesh to repair unwanted hernias. Here, we presented a facile strategy to develop an anti-fouling coating consisting of zwitterionic poly(carboxybetaine methacrylate) (PCBMA), which could prohibit protein adsorption to endow PP mesh with anti-inflammatory efficacy. The incorporation of PCBMA coating had little impact on the raw features of PP mesh. While the modified mesh PCBMA-PP possessed noticeable hydrophilicity increase and surface charge reduction. The excellent lubricity and surface stability enabled PCBMA-PP to exhibit superior anti-fouling capacity, thus efficiently inhibiting the adsorption of proteins. In vivo experiments showed that incorporating the PCBMA layer could provide PP meshes with outstanding anti-inflammatory effects and tissue compatibility for repairing hernias.

Hydroxyapatite formation in biomimetic synthesis with the interface of a pDA@SIS membrane

Porcine decellularized small intestine submucosa (SIS) is a collagen membrane, which offers great potential as an organic substrate template in mineralization processes due to its good biodegradability and biocompatibility. However, a long period of mineralization and low efficiency are apparent, and the mechanism of collagen fiber mineralization has often been neglected in the previous literature. Thus, in this paper, we present a novel model of biomimetic collagen mineralization which uses dopamine (DA) molecules with the activating and retouching function of SIS collagen membranes and regulating collagen mineralization to construct the structure of mineralized collagen hard tissues. The crystal biomimetic mineralization growth of calcium phosphate on membranes is studied in different solid-liquid interfaces with a double ion self-assembled diffusion system under the simulated physiological microenvironment. In the system, pDA@SIS membranes are used to control the concentration of Ca²⁺ and PO₄ ^3- ionic diffusion to generate supersaturation reaction conditions in 1-14 days. The system can successfully obtain polycrystals with low crystallinity on the pDA-collagen complex template surface of collagen fibers and along the collagen fibers. It initiates a generalized bionic mineralization pathway which can reduce the nucleation interfacial energy to promote rapid hydroxyapatite (HAP) nucleation and crystallization and accelerate the rate of collagen fiber mineralization. The pDA@SIS mineralized collagen membrane shows good biocompatibility with 100% cellular activity in the CCK-8 test, which significantly improved the adhesion proliferation of MC3T3-E1 cells. The pDA-SIS collagen complex, as a new type of mineralization template, may propose a new collagen mineralization strategy to produce a mineralized pDA@SIS scaffold bone-like material for tissue engineering or can potentially be applied in bone repair and regeneration.

Mussel-inspired polydopamine-mediated surface modification of freeze-cast poly (ε-caprolactone) scaffolds for bone tissue engineering applications

There are many methods used to fabricate the scaffolds for tissue regeneration, among which freeze casting has attracted a great deal of attention due to the capability to create a unidirectional structure. In this study, polycaprolactone (PCL) scaffolds were fabricated by freeze-casting technology in order to create porous microstructure with oriented open-pore channels. To induce biomineralization, and to improve hydrophilicity and cell interactions, mussel-inspired polydopamine (PDA) was coated on the surface of the freeze-cast PCL constructs. Then, the synergistic effects of oriented microstructure and deposited layer on efficient reconstruction of injured bone were studied. Microscopic observations demonstrated that, the coated layer did not show any special change in lamellar microstructure of the scaffolds. Water-scaffold interactions were evaluated by contact angle measurements, and they demonstrated strong enhancement in the hydrophilicity of the polymeric scaffolds after PDA coating. Biodegradation ratio and water uptake evaluation confirmed an increase in the measured values after PDA precipitation. The biomineralization of the PDA-coated scaffolds was characterized by field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD). Obtained results confirmed biomineralization of the constructs after a 28-day immersion in a simulated body fluid (SBF) solution. Mechanical analysis demonstrated higher compressive strength after PDA coating. L929 fibroblast cell viability and attachment illustrated that PDA-coated PCL scaffolds are able to support cell adhesion and proliferation. The increased secretion of alkaline phosphatase (ALP) after culturing osteosarcoma cell lines (MG-63) revealed the initial capability of scaffolds to induce bone regeneration. Therefore, the PDA-coated scaffolds introduce a promising approach for bone tissue engineering application.

Surface modification of small intestine submucosa in tissue engineering

With the development of tissue engineering, the required biomaterials need to have the ability to promote cell adhesion and proliferation in vitro and in vivo. Especially, surface modification of the scaffold material has a great influence on biocompatibility and functionality of materials. The small intestine submucosa (SIS) is an extracellular matrix isolated from the submucosal layer of porcine jejunum, which has good tissue mechanical properties and regenerative activity, and is suitable for cell adhesion, proliferation and differentiation. In recent years, SIS is widely used in different areas of tissue reconstruction, such as blood vessels, bone, cartilage, bladder and ureter, etc. This paper discusses the main methods for surface modification of SIS to improve and optimize the performance of SIS bioscaffolds, including functional group bonding, protein adsorption, mineral coating, topography and formatting modification and drug combination. In addition, the reasonable combination of these methods also offers great improvement on SIS surface modification. This article makes a shallow review of the surface modification of SIS and its application in tissue engineering.

The importance of developing relevant animal models to assess existing and new materials

PURPOSE OF REVIEW

We summarize the recent literature on the use of different animal models for testing existing and new materials for treatment of pelvic organ prolapse.

RECENT FINDINGS

A wide spectrum of animal models is being used in urogynecology, both for the study of physiologic and pathophysiologic processes, training in surgical procedures, yet mainly to study the host response to implant materials. The quality of studies is variable, and procedures, read-outs, and reporting are not standardized. This makes comparison very difficult. The research community is experimenting with different knitting patterns, novel polymers, bioactivation, as well as resorbable rather than durable implants. Outcomes of the experiments are dependent on the location of implantation. Lighter polypropylene constructs seem to induce a less vigorous host response than elder heavier products. Modification of the surface yields contradictory findings. Resorbable acellular collagen matrices may be reintroduced as prophylactically inserted support structures.

SUMMARY

Although animal experimentation with novel candidate implants is advocated, there is a lack of standardization in reporting. The concept of resorbable construct is being revived, as durable materials have caused clinical graft-related complications. Large animal experiments seem to provide interesting and more comprehensive information, yet their use may be contested.

Small intestinal submucosa: superiority, limitations and solutions, and its potential to address bottlenecks in tissue repair

Small intestinal submucosa (SIS) has attracted much attention in tissue repair because it can provide plentiful bioactive factors and a biomimetic three-dimensional microenvironment to induce desired cellular functions.

Mussel-inspired copolymer-coated polypropylene mesh with anti-adhesion efficiency for abdominal wall defect repair

Construction of anti-adhesive polypropylene meshes through the in situ copolymerization grafting of poly(ethylene glycol) methacrylate and dopamine methacrylamide.

Current trends and future perspectives in pelvic reconstructive surgery

Pelvic organ prolapse is a prevalent disorder with a high lifetime incidence of surgical repair. Pelvic organ prolapse surgery has greatly evolved over the past years, and pelvic floor reconstructive surgeons are faced with a vast array of treatment options for their patients. Our review article illustrates the current trends and future perspectives for the surgical treatment of pelvic organ prolapse.

Polydopamine-Assisted Surface Modification for Bone Biosubstitutes

Polydopamine (PDA) prepared in the form of a layer of polymerized dopamine (DA) in a weak alkaline solution has been used as a versatile biomimetic surface modifier as well as a broadly used immobilizing macromolecule. This review mainly discusses the progress of biomaterial surface modification inspired by the participation of PDA in bone tissue engineering. A comparison between PDA-assisted coating techniques and traditional surface modification applied to bone tissue engineering is first presented. Secondly, the chemical composition and the underlying formation mechanism of PDA coating layer as a unique surface modifier are interpreted and discussed. Furthermore, several typical examples are provided to evidence the importance of PDA-assisted coating techniques in the construction of bone biosubstitutes and the improvement of material biocompatibility. Nowadays, the application of PDA as a superior surface modifier in multifunctional biomaterials is drawing tremendous interests in bone tissue scaffolds to promote the osteointegration for bone regeneration.