The formation of nanostructures on titanium implant surfaces is a promising strategy to modulate cell adhesion and differentiation, which are crucial for future application in bone regeneration. The aim of this study was to investigate how the nanotube diameter and/or nanomechanical properties alter human osteoblast like cell (Saos-2) adhesion, growth and osteogenic differentiation in vitro. Nanotubes, with diameters ranging from 24 to 66 nm, were fabricated on a commercially pure titanium (cpTi) surface using anodic oxidation with selected end potentials of 10 V, 15 V and 20 V. The cell response was studied in vitro on untreated and nanostructured samples using a measurement of metabolic activity, cell proliferation, alkaline phosphatase activity and qRT-PCR, which was used for the evaluation of osteogenic marker expression (collagen type I, osteocalcin, RunX2). Early cell adhesion was investigated using SEM and ELISA. Adhesive molecules (vinculin, talin), collagen and osteocalcin were also visualized using confocal microscopy. Moreover, the reduced elastic modulus and indentation hardness of nanotubes were assessed using a TriboIndenter™. Smooth and nanostructured cpTi both supported cell adhesion, proliferation and bone-specific mRNA expression. The nanotubes enhanced collagen type I and osteocalcin synthesis, compared to untreated cpTi, and the highest synthesis was observed on samples modified with 20 V nanotubes. Significant differences were found in the cell adhesion, where the vinculin and talin showed a dot-like distribution. Both the lowest reduced elastic modulus and indentation hardness were assessed from 20 V samples. The nanotubes of mainly 20 V samples showed a high potential for their use in bone implantation.

Herein we describe the core/shell centrifugal spinning process to deliver susceptible bioactive molecules.

Bone and cartilage are tissues of a three-dimensional (3D) nature. Therefore, scaffolds for their regeneration should support cell infiltration and growth in all 3 dimensions. To fulfill such a requirement, the materials should possess large, open pores. Centrifugal spinning is a simple method for producing 3D fibrous scaffolds with large and interconnected pores. However, the process of bone regeneration is rather complex and requires additional stimulation by active molecules. In the current study, we introduced a simple composite scaffold based on platelet adhesion to poly-ε-caprolactone 3D fibers. Platelets were used as a natural source of growth factors and cytokines active in the tissue repair process. By immobilization in the fibrous scaffolds, their bioavailability was prolonged. The biological evaluation of the proposed system in the MG-63 model showed improved metabolic activity, proliferation and alkaline phosphatase activity in comparison to nonfunctionalized fibrous scaffold. In addition, the response of cells was dose dependent with improved biocompatibility with increasing platelet concentration. The results demonstrated the suitability of the system for bone tissue.

Purpose: Incisional hernia repair is an unsuccessful field of surgery, with long-term recurrence rates reaching up to 50% regardless of technique or mesh material used. Various implants and their positioning within the abdominal wall pose numerous long-term complications that are difficult to treat due to their permanent nature and the chronic foreign body reaction they trigger. Materials mimicking the 3D structure of the extracellular matrix promote cell adhesion, proliferation, migration, and differentiation. Some electrospun nanofibrous scaffolds provide a topography of a natural extracellular matrix and are cost effective to manufacture. Materials and methods: A composite scaffold that was assembled out of a standard polypropylene hernia mesh and poly-ε-caprolactone (PCL) nanofibers was tested in a large animal model (minipig), and the final scar tissue was subjected to histological and biomechanical testing to verify our in vitro results published previously. Results: We have demonstrated that a layer of PCL nanofibers leads to tissue overgrowth and the formation of a thick fibrous plate around the implant. Collagen maturation is accelerated, and the final scar is more flexible and elastic than under a standard polypropylene mesh with less pronounced shrinkage observed. However, the samples with the composite scaffold were less resistant to distracting forces than when a standard mesh was used. We believe that the adverse effects could be caused due to the material assembly, as they do not comply with our previous results. Conclusion: We believe that PCL nanofibers on their own can cause enough fibroplasia to be used as a separate material without the polypropylene base, thus avoiding potential adverse effects caused by any added substances.

Nanofibres enriched with bioactive molecules, as actively acting scaffolds, play an important role in tissue engineering.