Hydroxyapatite/alginate/gellan gum inks with osteoconduction and osteogenic potential for bioprinting bone tissue analogues.

There is a growing demand for engineered bone tissues custom-designed to match the patient-specific defect size and in vitro models for studying bone diseases and/or drug screening. Herein, we propose a bioprinted bone tissue construct using SaOs-2 cells within alginate/gellan gum/hydroxyapatite inks. Different ink formulations were developed with varying hydroxyapatite content and then evaluated for viscoelasticity, printability, biomineralization properties, post-printing viability, proliferation, metabolic activity, and osteogenic phenotype of SaOs-2-encapsulated cells.

Prevascularized spongy-like hydrogels maintain their angiogenic potential after prolonged hypothermic storage.

The chronic shortage of organs and tissues for transplantation represents a dramatic burden on healthcare systems worldwide. Tissue engineering offers a potential solution to address these shortages, but several challenges remain, with prevascularization being a critical factor for in vivo survival and integration of tissue engineering products. Concurrently, a different challenge hindering the clinical implementation of such products, regards their efficient preservation from the fabrication site to the bedside.

Effect of photobiomodulation on the behaviour of mesenchymal stem cells in three-dimensional cultures.

Photobiomodulation (PBM) has been proposed as a strategy to improve the regenerative capacity of human adipose-derived stem cells (hASCs). Yet, this effect has been proved in 2D culture conditions. To analyze the effect of different doses of laser irradiation (660 nm) with different levels of energy (1 J, 2 J and 6 J) on hASCs cultured at 2D and 3D conditions.

Human adipose-derived mesenchymal stem cells laden in gellan gum spongy-like hydrogels for volumetric muscle loss treatment.

Background: volumetric muscle loss (VML) is a traumatic massive loss of muscular tissue which frequently leads to amputation, limb loss, or lifetime disability. The current medical intervention is limited to autologous tissue transfer, which usually leads to non-functional tissue recovery. Tissue engineering holds a huge promise for functional recovery.

Gellan gum-based hydrogels support the recreation of the dermal papilla microenvironment.

The dermal papilla (DP), a specialized compartment within the hair follicle, regulates hair growth. However, human DP cells rapidly lose their inductivity in 2D-culture given the loss of positional and microenvironmental cues. Spheroids have been capable of recreating the 3D intercellular organization of DP cells, however, DP cell-matrix interactions are poorly represented.

Spongy-like hydrogels prevascularization with the adipose tissue vascular fraction delays cutaneous wound healing by sustaining inflammatory cell influx.

In vitro prevascularization is one of the most explored approaches to foster engineered tissue vascularization. We previously demonstrated a benefit in tissue neovascularization by using integrin-specific biomaterials prevascularized by stromal vascular fraction (SVF) cells, which triggered vasculogenesis in the absence of extrinsic growth factors. SVF cells are also associated to biological processes important in cutaneous wound healing.

Preclinical research studies for treating severe muscular injuries: focus on tissue-engineered strategies.

Severe skeletal muscle injuries are a lifelong trauma with limited medical solutions. Significant progress has been made in developing in vitro surrogates for treating such trauma. However, more attention is needed when translating these approaches to the clinic.

Integrin-specific hydrogels for growth factor-free vasculogenesis.

Integrin-binding biomaterials have been extensively evaluated for their capacity to enable de novo formation of capillary-like structures/vessels, ultimately supporting neovascularization in vivo. Yet, the role of integrins as vascular initiators in engineered materials is still not well understood. Here, we show that αvβ3 integrin-specific 3D matrices were able to retain PECAM1 cells from the stromal vascular fraction (SVF) of adipose tissue, triggering vasculogenesis in vitro in the absence of extrinsic growth factors.

Mechanomodulatory biomaterials prospects in scar prevention and treatment.

Scarring is a major clinical issue that affects a considerable number of patients. The associated problems go beyond the loss of skin functionality, as scars bring aesthetic, psychological, and social difficulties. Therefore, new strategies are required to improve the process of healing and minimize scar formation.

3D bioprinting of gellan gum-based hydrogels tethered with laminin-derived peptides for improved cellular behavior.

The treatment of skeletal muscle defects is still a topic of noteworthy concern since surgical intervention is not capable of recovering muscle function. Herein, we propose myoblasts laden in laminin-inspired biofunctionalized gellan gum hydrogels as promising tissue-engineered skeletal muscle surrogates. Gellan gum-based hydrogels were developed by combining native gellan gum (GG) and GG tethered with laminin-derived peptides (CIKVAVS (V), KNRLTIELEVRTC (T) or RKRLQVQLSIRTC (Q)), using different polymer content (0.

Injectable laminin-biofunctionalized gellan gum hydrogels loaded with myoblasts for skeletal muscle regeneration.

Moderate muscular injuries that exceed muscular tissue's auto-healing capacity are still a topic of noteworthy concern. Tissue engineering appeared as a promising therapeutic strategy capable of overcoming this unmet clinical need. To attain such goal, herein we propose an in situ-crosslinking gellan gum (GG)-based hydrogel tethered with a skeletal muscle-inspired laminin-derived peptide RKRLQVQLSIRTC(Q) and encapsulated with skeletal muscle cells (SMCs).

Micropatterned gellan gum-based hydrogels tailored with laminin-derived peptides for skeletal muscle tissue engineering.

The efficacy of current therapies for skeletal muscle disorders/injuries are limited urging the need for new treatments. Skeletal muscle tissue engineered platforms represent a promising tool to shed light on the pathophysiology of skeletal muscle disorders/injuries and to investigate the efficacy of new therapies. Herein, we developed a skeletal muscle platform composed of aligned and differentiated myoblasts on micropatterned gellan gum (GG)-based hydrogels tailored with a laminin-derived peptide.

Micropatterned Silk-Fibroin/Eumelanin Composite Films for Bioelectronic Applications.

There has been growing interest in the use of natural bionanomaterials and nanostructured systems for diverse biomedical applications. Such materials can confer unique functional properties as well as address concerns pertaining to sustainability in production. In this work, we propose the biofabrication of micropatterned silk fibroin/eumelanin composite thin films to be used in electroactive and bioactive applications in bioelectronics and biomedical engineering.

Correction: vascularization of tissue engineered constructs by non-viral delivery of pro-angiogenic genes.

Correction for 'In vitro vascularization of tissue engineered constructs by non-viral delivery of pro-angiogenic genes' by Helena R. Moreira et al., Biomater.

In vitro vascularization of tissue engineered constructs by non-viral delivery of pro-angiogenic genes.

Vascularization is still one of the major challenges in tissue engineering. In the context of tissue regeneration, the formation of capillary-like structures is often triggered by the addition of growth factors which are associated with high cost, bolus release and short half-life. As an alternative to growth factors, we hypothesized that delivering genes-encoding angiogenic growth factors to cells in a scaffold microenvironment would lead to a controlled release of angiogenic proteins promoting vascularization, simultaneously offering structural support for new matrix deposition.

Tailoring Gellan Gum Spongy-Like Hydrogels' Microstructure by Controlling Freezing Parameters.

Gellan gum (GG) spongy-like hydrogels have been explored for different tissue engineering (TE) applications owing to their highly attractive hydrogel-like features, and improved mechanical resilience and cell performance. Although the whole process for the preparation of these materials is well-defined, we hypothesized that variations occurring during the freezing step lead to batch-to-batch discrepancies. Aiming to address this issue, two freezing devices were tested, to prepare GG spongy-like hydrogels in a more reproducible way.

Electric Phenomenon: A Disregarded Tool in Tissue Engineering and Regenerative Medicine.

Tissue engineering and regenerative medicine (TERM) are paving the way to the generation of functional and mature biological tissues that closely emulate cellular, biochemical, and mechanical cues. Electrical fields in the human body modulate myriad biological processes, such as synapses, muscle contraction, hearing, and wound healing, which were disregarded in TERM until recently. To preserve and improve tissue electrophysiology, cells can be loaded in electroactive biomaterials and stimulated with exogenous electrical fields.

Lactoferrin-Hydroxyapatite Containing Spongy-Like Hydrogels for Bone Tissue Engineering.

The development of bioactive and cell-responsive materials has fastened the field of bone tissue engineering. Gellan gum (GG) spongy-like hydrogels present high attractive properties for the tissue engineering field, especially due to their wide microarchitecture and tunable mechanical properties, as well as their ability to entrap the responsive cells. Lactoferrin (Lf) and Hydroxyapatite (HAp) are bioactive factors that are known to potentiate faster bone regeneration.

Hydrogel-Based Strategies to Advance Therapies for Chronic Skin Wounds.

Chronic skin wounds are the leading cause of nontraumatic foot amputations worldwide and present a significant risk of morbidity and mortality due to the lack of efficient therapies. The intrinsic characteristics of hydrogels allow them to benefit cutaneous healing essentially by supporting a moist environment. This property has long been explored in wound management to aid in autolytic debridement.

Generation of Gellan Gum-Based Adipose-Like Microtissues.

Adipose tissue is involved in many physiological processes. Therefore, the need for adipose tissue-like analogues either for soft tissue reconstruction or as in vitro testing platforms is undeniable. In this work, we explored the natural features of gellan gum (GG) to recreate injectable stable adipose-like microtissues.

Electroactive Gellan Gum/Polyaniline Spongy-Like Hydrogels.

The ability of electroactive materials to influence and modulate cell behavior has been revealing great potential, especially in the field of skeletal muscle tissue engineering. Herein, we propose PANi-GG electroactive spongy-like hydrogels as potential materials to modulate myoblast bioresponse. polyaniline (PANi) adds electroconductiviy to gellan gum (GG) spongy-like hydrogels that hold a high resemblance to the extracellular matrix (ECM), that is, water content, mechanical properties, and microarchitecture, and that can be further tuned to meet muscle tissue properties.

Differentiation of osteoclast precursors on gellan gum-based spongy-like hydrogels for bone tissue engineering.

Bone tissue engineering with cell-scaffold constructs has been attracting a lot of attention, in particular as a tool for the efficient guiding of new tissue formation. However, the majority of the current strategies used to evaluate novel biomaterials focus on osteoblasts and bone formation, while osteoclasts are often overlooked. Consequently, there is limited knowledge on the interaction between osteoclasts and biomaterials.

Gellan Gum Hydrogels with Enzyme-Sensitive Biodegradation and Endothelial Cell Biorecognition Sites.

The survival of a biomaterial or tissue engineered construct is mainly hampered by the deficient microcirculation in its core, and limited nutrients and oxygen availability to the implanted or colonizing host cells. Aiming to address these issues, we herein propose bioresponsive gellan gum (GG) hydrogels that are biodegradable by metalloproteinase 1 (MMP-1) and enable endothelial cells adhesion and proliferation. GG is chemically functionalized with divinyl sulfone (DVS) and then biofunctionalized with thiol cell-adhesive peptides (T1 or C16) to confer GG endothelial cell biorecognition cues.