Journal of Biomedical Materials Research. Part A

Estrogen deficiency, long-term immobilization, and/or aging are commonly related to bone mass loss, thus increasing the risk of fractures. One option for bone replacement in injuries caused by either traumas or pathologies is the use of orthopedic cement based on polymethylmethacrylate (PMMA). Nevertheless, its reduced bioactivity may induce long-term detachment from the host tissue, resulting in the failure of the implant. In view of this problem, we developed an alternative PMMA-based porous cement (pPMMA) that favors cell invasion and improves osteointegration with better biocompatibility...

Hydrogel cell encapsulation devices are a common approach to reduce the need for chronic systemic immunosuppression in allogeneic cell product transplantation. Macroencapsulation approaches are an appealing strategy, as they maximize graft retrievability and cell dosage within a single device; however, macroencapsulation devices face oxygen transport challenges as geometries increase from preclinical to clinical scales. Device design guided by computational approaches can facilitate graft oxygen availability to encapsulated cells in vivo but is limited without accurate measurement of oxygen levels within the transplant site and graft...

Mesenchymal stem cell-derived secretome represents an emerging acellular therapeutic which possess significant opportunity for clinical applications due to its anti-inflammatory, immunomodulatory, and wound healing properties. However, maintaining therapeutic efficacy and ensuring stability of cell-based products is challenging, requiring a robust delivery method. Therefore, we designed a hydrogel-based scaffold loaded with CK Cell Technologies' proprietary Mesenchymal stem cell-secretome for controlled release treatment of acute and chronic wounds...

RNA-based therapeutics have gained traction for the prevention and treatment of a variety of diseases. However, their fragility and immunogenicity necessitate a drug carrier. Lipid nanoparticles (LNPs) have emerged as the predominant delivery vehicle for RNA therapeutics. An important component of LNPs is the ionizable lipid (IL), which is protonated in the acidic environment of the endosome, prompting cargo release into the cytosol. Currently, there is growing evidence that the structure of IL lipid tails significantly impacts the efficacy of LNP-mediated mRNA translation...

Critical-sized bone defects pose a significant challenge in advanced healthcare due to limited bone tissue regenerative capacity. The complex interplay of numerous overlapping variables hinders the development of multifunctional biocomposites. Phytochemicals show promise in promoting bone growth, but their dose-dependent nature and physicochemical properties halt clinical use. To develop a comprehensive solution, a 3D-printed (3DP) extrusion-based tricalcium phosphate-polycaprolactone (TCP-PCL) scaffold is augmented with quercetin and potassium chloride (KCl)...

Sponge-like materials made from regenerated silk fibroin biopolymers are a tunable and advantageous platform for in vitro engineered tissue culture and in vivo tissue regeneration. Anisotropic, three-dimensional (3D) silk fibroin sponge-like scaffolds can mimic the architecture of contractile muscle. Herein, we use silk fibroin solution isolated from the cocoons of Bombyx mori silkworms to form aligned sponges via directional ice templating in a custom mold with a slurry of dry ice and ethanol. Hydrated tensile mechanical properties of these aligned sponges were evaluated as a function of silk polymer concentration (3% or 5%), freezing time (50% or 100% ethanol), and post-lyophilization method for inducing crystallinity (autoclaving, water annealing)...

The physicochemical properties of grafting materials affect the quality of the osteointegration, resorption rate, and the new bone (NB) formation. This study assessed the physicochemical properties and integration of a low temperature deproteinized bovine bone xenograft (BBX), referred to as optimized MoaBone® (OMB). This novel BBX was physiochemically characterized both pre and post chemical bleaching and sterilization by gamma irradiation. OMB was compared to two commercial BBX; Bio-Oss® (BO) and MoaBone® (MB) using a rabbit cranial model...

Currently available focal knee resurfacing implants (FKRIs) are fully or partially composed of metals, which show a large disparity in elastic modulus relative to bone and cartilage tissue. Although titanium is known for its excellent osseointegration, the application in FKRIs can lead to potential stress-shielding and metal implants can cause degeneration of the opposing articulating cartilage due to the high resulting contact stresses. Furthermore, metal implants do not allow for follow-up using magnetic resonance imaging (MRI)...

Dental enamel is a mineralized extracellular matrix, and enamel defect is a common oral disease. However, the self-repair capacity of enamel is limited due to the absence of cellular components and organic matter. Efficacy of biomimetic enamel mineralization using calcium phosphate ion clusters (CPICs), is an effective method to compensate for the limited self-healing ability of fully developed enamel. Preparing and stabilizing CPICs presents a significant challenge, as the addition of certain stabilizers can diminish the mechanical properties or biosafety of mineralized enamel...

Diabetic wounds environment is over-oxidized, over-inflammatory, leading to difficulties in regenerating blood vessels, and retardation of healing in diabetic wounds. Therefore, diabetic wounds can be treated from the perspective of scavenging oxidative free radicals and reducing the level of inflammation. Herein, we report a bioactive poly(salicylic acid)-poly(citric acid) (FPSa-PCG) hydrogel for diabetic wound repair. The FPSa-PCG hydrogel shows abilities of antioxidation, anti-inflammation, and regulation of macrophage phenotype...

Induced Tregs (iTregs) have great promise in adoptive immunotherapy for treatment of autoimmune diseases. This report investigates the impacts of substrate stiffness on human Treg induction, providing a powerful yet simple approach to improving production of these cells. Conventional CD4+ human T cells were activated on materials of different elastic modulus and cultured under suppressive conditions. Enhanced Treg induction was observed on softer materials as early as 3 days following activation and persisted for multiple weeks...

Maurizio Sabbatini , Valentina Piffanelli , Francesca Boccafoschi , Silvia Gatti , Filippo Renò , Michela Bosetti , Massimiliano Leigheb , Alessandro Massè , Cannas Mario , Different apoptosis modalities in periprosthetic membranes, Biomed. Mater. Res., 92A: 175-184. DOI: 10.1002/jbm.a.32349. The journal publishes this Expression of Concern to notify the readers regarding irregularities identified in Figure 1A and 1B of the above article, published online on 22 January 2009, in Wiley Online Library (wileyonlinelibrary...

This work presents the effect of the silicocarnotite (SC) and nagelschmidtite (Nagel) phases on in vitro osteogenesis. The known hydroxyapatite of biological origin (BHAp) was used as a standard of osteoconductive characteristics. The evaluation was carried out in conventional and osteogenic media for comparative purposes to assess the osteogenic ability of the bioceramics. First, the effect of the material on cell viability at 24 h, 7 and 14 days of incubation was evaluated. In addition, cell morphology and attachment on dense bioceramic surfaces were observed by fluorescence microscopy...

The ever-growing need for new tissue and organ replacement approaches paved the way for tissue engineering. Successful tissue regeneration requires an appropriate scaffold, which allows cell adhesion and provides mechanical support during tissue repair. In this light, an interpenetrating polymer network (IPN) system based on biocompatible polysaccharides, dextran (Dex) and gellan (Ge), was designed and proposed as a surface that facilitates cell adhesion in tissue engineering applications. The new matrix was developed in glycerol, an unconventional solvent, before the chemical functionalization of the polymer backbone, which provides the system with enhanced properties, such as increased stiffness and bioadhesiveness...

Bone tissue is a highly vascularized tissue. When constructing tissue-engineered bone models, both the osteogenic and angiogenic capabilities of the construct should be carefully considered. However, fabricating a vascularized tissue-engineered bone to promote vascular formation and bone generation, while simultaneously establishing nutrition channels to facilitate nutrient exchange within the constructs, remains a significant challenge. Triaxial bioprinting, which not only allows the independent encapsulation of different cell types while simultaneously forming nutrient channels, could potentially emerge as a strategy for fabricating vascularized tissue-engineered bone...

Porous titanium exhibits low elastic modulus and porous structure is thought to be a promising implant in bone defect repair. However, the bioinert and low mechanical strength of porous titanium have limited its clinical application, especially in load-bearing bone defect repair. Our previous study has reported an infiltration casting and acid corrosion (IC-AC) method to fabricate a novel porous titanium (pTi) with 40% porosity and 0.4 mm pore diameter, which exerts mechanical property matching with cortical bone and interconnected channels...

Combinations of different biomaterials with their own advantages as well as functionalization with other components have long been implemented in tissue engineering to improve the performance of the overall material. Biomaterials, particularly hydrogel platforms, have shown great potential for delivering compounds such as drugs, growth factors, and neurotrophic factors, as well as cells, in neural tissue engineering applications. In central the nervous system, astrocyte reactivity and glial scar formation are significant and complex challenges to tackle for neural and functional recovery...

The increasing prevalence of implant-associated infections (IAI) in orthopedics remains a public health challenge. Calcium phosphates (CaPs) are critical biomaterials in dental treatments and bone regeneration. It is highly desirable to endow CaPs with antibacterial properties. To achieve this purpose, we developed a photocrosslinked methacrylated alginate co-calcium phosphate cement (PMA-co-PCPC) with antibacterial properties, using α-tricalcium phosphate (α-TCP) powders with 16% amorphous contents as solid phase, liquid phases containing CuCl2 and SrCl2 as an inhibitor, and CaCl2 as an activator to construct PCPC...

Extracellular matrix-based bio-scaffolds are useful for tissue engineering as they retain the unique structural, mechanical, and physiological microenvironment of the tissue thus facilitating cellular attachment and matrix activities. However, considering its potential, a comprehensive understanding of the protein profile remains elusive. Herein, we evaluate the impact of decellularization on the human amniotic membrane (hAM) based on its proteome profile, physicochemical features, as well as the attachment, viability, and proliferation of umbilical cord-derived mesenchymal stem cells (hUC-MSC)...

Pulmonary infections complicate chronic lung diseases requiring attention to both the pathophysiology and complexity associated with infection management. Patients with cystic fibrosis (CF) struggle with continuous bouts of pulmonary infections, contributing to lung destruction and eventual mortality. Additionally, CF patients struggle with airways that are highly viscous, with accumulated mucus creating optimal environments for bacteria colonization. The unique physiology and altered airway environment provide an ideal niche for bacteria to change their phenotype often becoming resistant to current treatments...