Search results for "tissue engineering."

The covalently immobilized antimicrobial peptide LL37 acts as a VEGF mimic and stimulates endothelial cell proliferation

2018

The chemical coupling of growth factors to solid substrates are discussed as an alternative to delivery systems. Utilizing entire proteins for this application is hampered by safety and stability considerations. Instead, growth factor mimicking peptides are of great interest for biomedical applications, such as tissue engineering, due to their purity and stability. The human cathelicidin derived antimicrobial peptide LL37, beside its microbicidal activity, was shown to stimulate endothelial cell growth when used in a soluble form. Here, in a novel approach, spacer mediated immobilization, but not direct conjugation of LL37, to a gold substrate was shown to result in a pronounced mitogenic e…

The impact of intercellular communication for the generation of complex multicellular prevascularized tissue equivalents

2019

In reconstructive surgery the use of prevascularized soft tissue equivalents is a promising approach for wound coverage of defects after tumor resection or trauma. However, in previous studies to generate soft tissue equivalents on collagen membranes, microcapillaries were restricted to superficial areas. In this study, to understand which factors were involved in the formation of these microcapillaries, the levels of the angiogenic factors vascular endothelial growth factor (VEGF), Interleukin-8 (IL-8), and basic fibroblast growth factor (bFGF) in the supernatants of the tissue equivalents were examined at various time points and conditions. Additionally, the influence of these factors on …

Scaffold vascularization in vivo driven by primary human osteoblasts in concert with host inflammatory cells.

2011

Successful cell-based tissue engineering requires a rapid and thorough vascularization in order to ensure long-term implant survival and tissue integration. The vascularization of a scaffold is a complex process, and is modulated by the presence of transplanted cells, exogenous and endogenous signaling proteins, and the host tissue reaction, among other influencing factors. This paper presents evidence for the significance of pre-seeded osteoblasts for the in vivo vascularization of a biodegradable scaffold. Human osteoblasts, cultured on silk fibroin micronets in vitro, migrated throughout the interconnected pores of the scaffold and produced extensive bone matrix. When these constructs we…

Sonic hedgehog promotes angiogenesis and osteogenesis in a coculture system consisting of primary osteoblasts and outgrowth endothelial cells.

2009

A number of previous studies documented the angiogenic potential of outgrowth endothelial cells in vitro and in vivo and provided evidence that therapeutic success could depend on coculture or coimplantation strategies. Thus, deeper insight into the molecular mechanisms underlying this pro-angiogenic effect of cocultures might provide new translational options for tissue engineering and regenerative medicine. One promising signaling pathway in bone repair involved in neoangiogenesis and bone formation is the sonic hedgehog (Shh) pathway. In this article, we focus on the effect of Shh on the formation of microvessel-like structures and osteoblastic differentiation in cocultures of primary os…

Visions for regenerative medicine: interface between scientific fact and science fiction.

2006

This article gives a brief overview of the authors' views on the future development of tissue engineering with respect to the challenges both to the materials and life sciences. Emphasis will be placed on the advantages of three-dimensional bioresorbable polymers in combination with relevant molecular cues and the application of autologous stem or progenitor cells. There is a requirement for much more diversity in the synthesis of so-called "intelligent" materials, which respond to external stimuli, as well as the development of novel drug and gene delivery systems. In addition, much more basic research is necessary in developmental biology and the application of modern cell and molecular b…

Effects of fabrication on the mechanics, microstructure and micromechanical environment of small intestinal submucosa scaffolds for vascular tissue e…

2013

In small intestinal submucosa scaffolds for functional tissue engineering, the impact of scaffold fabrication parameters on success rate may be related to the mechanotransductory properties of the final microstructural organization of collagen fibers. We hypothesized that two fabrication parameters, 1) preservation (P) or removal (R) of a dense collagen layer present in SIS and 2) SIS in a final dehydrated (D) or hydrated (H) state, have an effect on scaffold void area, microstructural anisotropy (fiber alignment) and mechanical anisotropy (global mechanical compliance). We further integrated our experimental measurements in a constitutive model to explore final effects on the micromechanic…

Editorial - Connecting the Dots: The Promises of Wharton's Jelly Mesenchymal Stem Cells for Tissue Repair and Regeneration

2011

Mesenchymal stem cells (MSC) constitute a variety of cellular populations which were described first about 35 years ago in the bone marrow (BM) stroma [1]. These years have foreseen an exponential increase of reports pointing out features, stemness, markers, tissue sources and clinical applications of these cells. Cells with MSC features can be isolated from virtually every adult organ in the body, as well from a group of fetus-associated sources (cells derived from the latter tissues are collectively known as perinatal stem cells) [2]. In recent years, the umbilical cord arose as a promising source of mesenchymal stem cells, which can be isolated in relatively high numbers (compared to BM)…

Biocompatible Polymers and Processing Techniques in Drug Delivery and Tissue Engineering

2013

Perinatal stem cells revisited: directions and indications at the crossroads between tissue regeneration and repair.

2013

Perinatal stem cells research attracted great interest worldwide in recent years. Foetus-associated tissues contain various populations of stem cells, most of which are comprised within the category of mesenchymal stem cells (MSCs). This special issue collects both reviews and original reports on all the perinatal stem cell types which are currently under investigation. These cells have multiple promising features: differentiative capacity towards mature cell types of all the three germ layers, hypoimmunogenicity in vitro and in vivo, ease of sourcing, ex vivo culture and stor- age. In particular, immune modulation is viewed as a prom- ising feature of many MSCs populations, since these cel…

Protein materials as sustainable non- and minimally invasive strategies for biomedical applications

2022

Protein-based materials have found applications in a wide range of biomedical fields because of their biocompatibility, biodegradability and great versatility. Materials of different physical forms including particles, hydrogels, films, fibers and microneedles have been fabricated e.g. as carriers for drug delivery, factors to promote wound healing and as structural support for the generation of new tissue. This review aims at providing an overview of the current scientific knowledge on protein-based materials, and selected preclinical and clinical studies will be reviewed in depth as examples of the latest progress within the field of protein-based materials, specifically focusing on non- …