Hydrogel-based microfluidics for vascular tissue engineering

In this work, we have explored 3-D co-culture of vasculogenic cells within a synthetically modified fibrin hydrogel. Fibrinogen was covalently linked with PEG-NHS in order to improve its degradability resistance and physico-optical properties. We have studied influences of the degree of protein PEGylation and the concentration of enzyme thrombin used for the gel preparation on cellular responses. Scanning electron microscopy analysis of prepared gels revealed that the degree of PEGylation and the concentration of thrombin strongly influenced microstructural characteristics of the protein hydrogel. Human umbilical vein endothelial cells (HUVECs) and human adipose-derived stem cells (hASCs), used as vasculogenic co-culture, could grow in 5:1 PEGylated fibrin gels prepared using 1:0.2 protein to thrombin ratio. This gel formulation supported hASCs and HUVECs spreading and the formation of cell extensions and cell-to-cell contacts. Expression of specific ECM proteins and vasculogenic process inherent cellular enzymatic activity were investigated by immunofluorescent staining, gelatin zymography, western blot and RT-PCR analysis. After evaluation of the optimal gel composition and PEGylation ratio, the hydrogel was utilized for investigation of vascular tube formation within a perfusable microfluidic system. The morphological development of this co-culture within a perfused hydrogel over 12 days led to the formation of interconnected HUVEC-hASC network. The demonstrated PEGylated fibrin microfluidic approach can be used for incorporating other cell types, thus representing a unique experimental platform for basic vascular tissue engineering and drug screening applications. © 2016 by De Gruyter

Platelet-Rich Plasma in Regenerative Medicine: Possible Applications in Management of Burns and Post-Burn Scars: A Review

Contribution of platelets in tissue regeneration and their possible application in regenerative medicine, which is primarilymediated via secretion of granular components following platelet activation, has been well established in the recent decades.Therefore, platelet rich plasma (PRP), as a portion of plasma with higher concentrations of platelets than the baseline level,is now an attractive therapeutic option in various medical fields mainly for tissue repair and regeneration following injuries.Burn injuries are devastating trauma with high rate of morbidities affecting several aspects of the patient’s life. They requirea long-time medical care and high costs. However, even following the best treatment procedures, post-burn scars areinevitable consequence of burn healing process. Therefore, development of new treatment modalities for both burn healingand prevention of post-burn scar establishment seems to be necessary. Regarding the well-known role of PRP in woundhealing, here we aimed to provide a comprehensive insight in the possible application of PRP as an adjuvant therapy forthe management of burn injuries and subsequent scars. In terms of the following keywords (individually or in combination),original/review articles were searched in PubMed, Scopus, and Google Scholar databases from 2009 to 2021: platelet richplasma, PRP therapy, platelet biology, platelet function, burn healing, burn scar, scar formation, burn management, woundhealing, regenerative medicine. All type of articles or book chapters in English language and relevant data were included inthis review. This review initially focused on PRP, its mechanisms of action, preparation methods, and available sources. Then,pathophysiology of burns and subsequent scars were discussed. Finally, their current conventional therapeutic modalities andimplication of PRP in their healing process were highlighted

Review on Kidney-Liver Crosstalk: Pathophysiology of Their Disorders

Kidney-liver crosstalk plays a crucial role in normal and certain pathological conditions. In pathologic states, bothrenal-induced liver damage and liver-induced kidney diseases may happen through these kidney-liver interactions.This bidirectional crosstalk takes place through the systemic conditions that mutually influence both the liver andkidneys. Ischemia and reperfusion, cytokine release and pro-inflammatory signaling pathways, metabolic acidosis,oxidative stress, and altered enzyme activity and metabolic pathways establish the base of this interaction betweenthe kidneys and liver. In these concomitant kidney-liver diseases, the survival rates strongly correlate with earlyintervention and treatment of organ dysfunction. Proper care of a nephrologist and hepatologist and the identificationof pathological conditions using biomarkers at early stages are necessary to prevent the complications induced by thiscomplex and potentially vicious cycle. Therefore, understanding the characteristics of this crosstalk is essential forbetter management. In this review, we discussed the available literature concerning the detrimental effects of kidneyfailure on liver functions and liver-induced kidney diseases

Fabrication and handling of 3D scaffolds based on polymers and decellularized tissues

Polymeric, ceramic and hybrid material-based three-dimensional (3D) scaffold or matrix structures are important for successful tissue engineering. While the number of approaches utilizing the use of cell-based scaffold and matrix structures is constantly growing, it is essential to provide a framework of their typical preparation and evaluation for tissue engineering. This chapter describes the fabrication of 3D scaffolds using -two--photon polymerization, decellularization and cell encapsulation methods and easy-to-use protocols allowing assessing the cell morphology, cytotoxicity and viability in these scaffolds

Time resolved 3D live-cell imaging on implants.

It is estimated that two million new dental implants are inserted worldwide each year. Innovative implant materials are developed in order to minimize the risk of peri-implant inflammations. The broad range of material testing is conducted using standard 2D, terminal, and invasive methods. The methods that have been applied are not sufficient to monitor the whole implant surface and temporal progress. Therefore, we built a 3D peri-implant model using a cylindrical implant colonized by human gingival fibroblasts. In order to monitor the cell response over time, a non-toxic LIVE/DEAD staining was established and applied to the new 3D model. Our LIVE/DEAD staining method in combination with the time resolved 3D visualization using Scanning Laser Optical Tomography (SLOT), allowed us to monitor the cell death path along the implant in the 3D peri-implant model. The differentiation of living and dead gingival fibroblasts in response to toxicity was effectively supported by the LIVE/DEAD staining. Furthermore, it was possible to visualize the whole cell-colonized implant in 3D and up to 63 hours. This new methodology offers the opportunity to record the long-term cell response on external stress factors, along the dental implant and thus to evaluate the performance of novel materials/surfaces

Non-Clear Cell Renal Cell Carcinoma: Molecular Pathogenesis, Innovative Modeling, and Targeted Therapeutic Approaches

Non-clear cell renal cell carcinomas (nccRCC) are a diverse group of kidney cancers with histopathologically and genetically heterogeneous features. About 25% of renal cell carcinomas (RCCs) are nccRCC types. The management and treatment of nccRCCs are rather limited, and the data are often estimated from studies in the more common clear cell renal cell carcinoma (ccRCC). Each subtype has its own distinctive biological and therapeutic profile. Our knowledge of the underlying biological features of nccRCC has directed and continues to shape the use of novel therapy targeting the main signaling pathways and leading to improved overall survival (OS) of the patients. This review discusses the characteristic molecular features of the major types of nccRCC and current cell-based and animal models for studying them. In the following, we highlighted major signaling pathways and therapeutic approaches for nccRCC patients

Evolution of organoid technology: Lessons learnt in Co-Culture systems from developmental biology

In recent years, the development of 3D organoids has opened new avenues of investigation into development, physiology, and regenerative medicine. Organoid formation and the process of organogenesis share common developmental pathways; thus, our knowledge of developmental biology can help model the complexity of different organs to refine organoids into a more sophisticated platform. The developmental process is strongly dependent on complex networks and communication of cell-cell and cell-matrix interactions among different cell populations and their microenvironment, during embryogenesis. These interactions affect cell behaviors such as proliferation, survival, migration, and differentiation. Co-culture systems within the organoid technology were recently developed and provided the highly physiologically relevant systems. Supportive cells including various types of endothelial and stromal cells provide the proper microenvironment, facilitate organoid assembly, and improve vascularization and maturation of organoids. This review discusses the role of the co-culture systems in organoid generation, with a focus on how knowledge of developmental biology has directed and continues to shape the development of more evolved 3D co-culture system-derived organoids

The In Vitro Cytotoxicity of Eremothecium oil and Its Components—Aromatic and Acyclic Monoterpene Alcohols

The microscopic fungi Eremothecium ashbyi and E. gossypii are known for their ability to synthetize essential oil, which has a composition similar to that of rose oil. The development of Eremothecium oil technology enables the production of rose-scented products, which are demanded by pharmaceutical, food, and perfumery industries. This study focuses on assessing the in vitro cytotoxicity of Eremothecium oil, in comparison with that of rose oil, using a combination of methods and two cell types (3T3 mouse fibroblast cell line and bone-marrow-derived mesenchymal stromal cells (BM-MSCs)). The Eremothecium oil samples possessed cytotoxic effects that varied among strains and batches. The revealed cytotoxicity level may be used to tailor the qualitative and quantitative composition of Eremothecium oil to achieve a particular quality in its end products. These results require further analysis using other cell types and assays based on measuring other cell functions

Skin tissue regeneration for burn injury

Abstract The skin is the largest organ of the body, which meets the environment most directly. Thus, the skin is vulnerable to various damages, particularly burn injury. Skin wound healing is a serious interaction between cell types, cytokines, mediators, the neurovascular system, and matrix remodeling. Tissue regeneration technology remarkably enhances skin repair via re-epidermalization, epidermal-stromal cell interactions, angiogenesis, and inhabitation of hypertrophic scars and keloids. The success rates of skin healing for burn injuries have significantly increased with the use of various skin substitutes. In this review, we discuss skin replacement with cells, growth factors, scaffolds, or cell-seeded scaffolds for skin tissue reconstruction and also compare the high efficacy and cost-effectiveness of each therapy. We describe the essentials, achievements, and challenges of cell-based therapy in reducing scar formation and improving burn injury treatment