Large-Volume Vascularized Muscle Grafts Engineered From Groin Adipose Tissue in Perfusion Bioreactor Culture.

Background: Muscle tissue engineering still remains a major challenge. An axial vascular pedicle and a perfusion bioreactor are necessary for the development and maintenance of a large-volume engineered muscle tissue to provide circulation within the construct. This study aimed to determine whether large-volume vascularized muscle-like constructs could be made from rat groin adipose tissue in a perfusion bioreactor.

In vitro enhancement and functional characterization of neurite outgrowth by undifferentiated adipose-derived stem cells.

Adipose‑derived stem cells (ASCs) can easily be obtained and expanded in vitro for use in autologous cell therapy. Via their production of cytokines and neurotrophic factors, transplanted ASCs provide neuroprotection, neovascularization and induction of axonal sprouting. However, the influencing mechanism of undifferentiated ASCs on nerve regeneration is currently only partially understood.

Anti-apoptotic protein Lifeguard does not act as a tumor marker in breast cancer.

The aim of the present study was to use an enzyme-linked immunosorbent assay (ELISA) to determine the concentrations of Lifeguard (LFG) protein in the serum of 36 patients diagnosed with breast cancer and to compare these values with the concentrations of LFG protein in the serum of 7 healthy volunteers in order to detect a possible association between the expression of LFG in the serum and the degree of malignancy of the disease. Although there is no direct association between the LFG protein concentration in the serum and the degree of malignancy of breast cancer, a statistically significant distribution of the concentration in all investigated samples was observed. This indicated an association between the LFG protein concentration in human serum with a currently unknown factor.

Characterization and Schwann Cell Seeding of up to 15.0 cm Long Spider Silk Nerve Conduits for Reconstruction of Peripheral Nerve Defects.

Nerve reconstruction of extended nerve defect injuries still remains challenging with respect to therapeutic options. The gold standard in nerve surgery is the autologous nerve graft. Due to the limitation of adequate donor nerves, surgical alternatives are needed.

What is the effect of nicotinic acetylcholine receptor stimulation on osteoarthritis in a rodent animal model?

Objectives: Despite the rising number of patients with osteoarthritis, no sufficient chondroprotective and prophylactic therapy for osteoarthritis has been established yet. The purpose of this study was to verify whether stimulation of the nicotinic acetylcholine receptor via nicotine has a beneficial effect on cartilage degeneration in the development of osteoarthritis and is capable of reducing the expression of proinflammatory cytokines and cartilage degrading enzymes in synovial membranes after osteoarthritis induction.

Methods: Experimental osteoarthritis was induced in Lewis rats using a standardized osteoarthritis model with monoiodoacetate.

In Vitro Evaluation of Spider Silk Meshes as a Potential Biomaterial for Bladder Reconstruction.

Reconstruction of the bladder by means of both natural and synthetic materials remains a challenge due to severe adverse effects such as mechanical failure. Here we investigate the application of spider major ampullate gland-derived dragline silk from the Nephila edulis spider, a natural biomaterial with outstanding mechanical properties and a slow degradation rate, as a potential scaffold for bladder reconstruction by studying the cellular response of primary bladder cells to this biomaterial. We demonstrate that spider silk without any additional biological coating supports adhesion and growth of primary human urothelial cells (HUCs), which are multipotent bladder cells able to differentiate into the various epithelial layers of the bladder.

TRIM21, a negative modulator of LFG in breast carcinoma MDA-MB-231 cells in vitro.

Lifeguard (LFG) is a transmembrane protein which is highly expressed in tissues of the hippocampus and the cerebellum, especially during postnatal development. This protein is responsible for the protection of neurons against Fas-induced apoptosis, and the same effect can be seen in tumor cells derived from mastocarcinoma. However, the molecular function of LFG and its regulation in the carcinogenesis of human breast cells remains to be elucidated.

Noninvasive Oxygen Monitoring in Three-Dimensional Tissue Cultures Under Static and Dynamic Culture Conditions.

We present a new method for noninvasive real-time oxygen measurement inside three-dimensional tissue-engineered cell constructs in static and dynamic culture settings in a laminar flow bioreactor. The OPAL system (optical oxygen measurement system) determines the oxygen-dependent phosphorescence lifetime of spherical microprobes and uses a two-frequency phase-modulation technique, which fades out the interference of background fluorescence from the cell carrier and culture medium. Higher cell densities in the centrum of the scaffolds correlated with lower values of oxygen concentration obtained with the OPAL system.

Three-Dimensional Modelling inside a Differential Pressure Laminar Flow Bioreactor Filled with Porous Media.

A three-dimensional computational fluid dynamics- (CFD-) model based on a differential pressure laminar flow bioreactor prototype was developed to further examine performance under changing culture conditions. Cell growth inside scaffolds was simulated by decreasing intrinsic permeability values and led to pressure build-up in the upper culture chamber. Pressure release by an integrated bypass system allowed continuation of culture.

Transdermal Nicotine Application Attenuates Cardiac Dysfunction after Severe Thermal Injury.

Background: Severe burn trauma leads to an immediate and strong inflammatory response inciting cardiac dysfunction that is associated with high morbidity and mortality. The aim of this study was to determine whether transdermal application of nicotine could influence the burn-induced cardiac dysfunction via its known immunomodulatory effects.

Material And Methods: A standardized rat burn model was used in 35 male Sprague Dawley rats.

Silks as scaffolds for skin reconstruction.

In this short review, we describe the use of high molecular weight proteins produced in the glands of several arthropods-commonly called silks-for the purpose to enhance human skin wound healing. To this end an extensive literature search has been performed, the publications have been categorized concerning silk preparation and application and summarized accordingly: Scaffolds to promote wound healing were prepared by processing the silks in different ways including solubilization of the protein fibers followed by casting or electrospinning. The silk scaffolds were additionally modified by coating or blending with the intention of further functionalization.

In planta production of ELPylated spidroin-based proteins results in non-cytotoxic biopolymers.

Background: Spider silk is a tear-resistant and elastic biopolymer that has outstanding mechanical properties. Additionally, exiguous immunogenicity is anticipated for spider silks. Therefore, spider silk represents a potential ideal biomaterial for medical applications.

Identification of reference genes and validation for gene expression studies in diverse axolotl (Ambystoma mexicanum) tissues.

For the precise quantitative RT-PCR normalization a set of valid reference genes is obligatory. Moreover have to be taken into concern the experimental conditions as they bias the regulation of reference genes. Up till now, no reference targets have been described for the axolotl (Ambystoma mexicanum).

Successful nucleofection of rat adipose-derived stroma cells with Ambystoma mexicanum epidermal lipoxygenase (AmbLOXe).

Introduction: Adipose-derived stroma cells (ASCs) are attractive cells for cell-based gene therapy but are generally difficult to transfect. Nucleofection has proven to be an efficient method for transfection of primary cells. Therefore, we used this technique to transfect ASCs with a vector encoding for Ambystoma mexicanum epidermal lipoxygenase (AmbLOXe) which is a promising bioactive enzyme in regenerative processes.

Observed changes in the morphology and phenotype of breast cancer cells in direct co-culture with adipose-derived stem cells.

Background: Regarding aesthetics and long-term stability, cell-assisted lipotransfer is a promising method for breast reconstruction. Here, autologous fat grafts enriched with autologous adipose-derived stem cells are transferred. However, as adipose-derived stem cells secrete high amounts of growth factors, potential risks of tumor reactivation remain.

Role of lifeguard β-isoform in the development of breast cancer.

In the last century there has been great progress in the treatment of breast cancer by improving drug and radiation therapy as well as surgical techniques. Despite this development, breast cancer remains a major cause of death among women in Europe and the US. The cause of breast cancer at the cellular level is still not fully understood.

Murine embryonic fibroblast cell lines differentiate into three mesenchymal lineages to different extents: new models to investigate differentiation processes.

Various diseases, injuries, and congenital abnormalities may result in degeneration and loss of organs and tissues. Recently, tissue engineering has offered new treatment options for these common, severe, and costly problems in human health care. Its application is often based on the usage of differentiated stem cells.

Intravenous transplantation of mesenchymal stromal cells to enhance peripheral nerve regeneration.

Peripheral nerve injury is a common and devastating complication after trauma and can cause irreversible impairment or even complete functional loss of the affected limb. While peripheral nerve repair results in some axonal regeneration and functional recovery, the clinical outcome is not optimal and research continues to optimize functional recovery after nerve repair. Cell transplantation approaches are being used experimentally to enhance regeneration.

Biomechanics and biocompatibility of woven spider silk meshes during remodeling in a rodent fascia replacement model.

Objective: The aim of this study was to investigate biomechanical and immunogenic properties of spider silk meshes implanted as fascia replacement in a rat in vivo model.

Background: Meshes for hernia repair require optimal characteristics with regard to strength, elasticity, and cytocompatibility. Spider silk as a biomaterial with outstanding mechanical properties is potentially suitable for this application.

Cultivation of keratinocytes and fibroblasts in a three-dimensional bovine collagen-elastin matrix (Matriderm®) and application for full thickness wound coverage in vivo.

New skin substitutes for burn medicine or reconstructive surgery pose an important issue in plastic surgery. Matriderm® is a clinically approved three-dimensional bovine collagen-elastin matrix which is already used as a dermal substitute of full thickness burn wounds. The drawback of an avital matrix is the limited integration in full thickness skin defects, depending on the defect size.

Bundles of spider silk, braided into sutures, resist basic cyclic tests: potential use for flexor tendon repair.

Repair success for injuries to the flexor tendon in the hand is often limited by the in vivo behaviour of the suture used for repair. Common problems associated with the choice of suture material include increased risk of infection, foreign body reactions, and inappropriate mechanical responses, particularly decreases in mechanical properties over time. Improved suture materials are therefore needed.

Mesenchymal stem cells maintain long-term in vitro stemness during explant culture.

The advantage of mesenchymal stem cells (MSC) in view of cell and/or tissue replacement after transplantation and their prolonged clinical use raises heavy debates not only in the fields of tissue engineering and regenerative medicine to date. Explant culture of umbilical cord (UC) tissue pieces for more than 190 days demonstrated a similar morphology and proliferation rate of outgrowing MSC as compared to UC tissue cultured for 15 days. Flow cytometric analysis revealed the expression of the typical UC-MSC markers CD73, CD90, and CD105 with concomitant absence of CD14, CD31, CD34, and CD45 in all MSC populations.