Hyaluronan: from extracellular glue to pericellular cue

Hydrogel-exosome system in tissue engineering: A promising therapeutic strategy

Characterized by their pivotal roles in cell-to-cell communication, cell proliferation, and immune regulation during tissue repair, exosomes have emerged as a promising avenue for "cell-free therapy" in clinical applications. Hydrogels, possessing commendable biocompatibility, degradability, adjustability, and physical properties akin to biological tissues, have also found extensive utility in tissue engineering and regenerative repair. The synergistic combination of exosomes and hydrogels holds the potential not only to enhance the efficiency of exosomes but also to collaboratively advance the tissue repair process. This review has summarized the advancements made over the past decade in the research of hydrogel-exosome systems for regenerating various tissues including skin, bone, cartilage, nerves and tendons, with a focus on the methods for encapsulating and releasing exosomes within the hydrogels. It has also critically examined the gaps and limitations in current research, whilst proposed future directions and potential applications of this innovative approach.

Hyaluronic acid modified extracellular vesicles targeting hepatic stellate cells to attenuate hepatic fibrosis

RATIONALE

Transforming growth factor-beta1 (TGF-β1) plays a pivotal role in promoting hepatic fibrosis, pirfenidone (PFD) could inhibit TGF-β1 signaling pathway to alleviate hepatic stellate cells (HSC) activation mediated hepatic fibrosis. The targeting delivery strategy of PFD to hepatic stellate cells is a challenge. Extracellular vesicles (EVs), cell-derived membranous particles are intraluminal nano-vesicles that play a vital role in intercellular communication, they also be considered as an ideal nano-carrier.

METHODS

In this study, we developed a target strategy to deliver PFD to HSC with CD44 over-expression by EVs, hyaluronic acid (HA) modified DSPE-PEG2000 endows the active targeting ability of activated HSCs to PFD-loaded EVs.

RESULTS

In both rat hepatic stellate cell line HSC-T6 and rat hepatocyte cell line BRL, HA@EVs-PFD demonstrated the capacity to down-regulate the expression of collagen-synthesis-related proteins and showed superior inhibition efficacy of HSC-T6 activation compared to free PFD. In hepatic fibrosis model, 4 weeks of HA@EVs-PFD treatment resulted in a reduction in liver collagen fibers, significant improvement in hepatic cell morphology, and amelioration of hepatic fibrosis.

CONCLUSIONS

HA@EVs-PFD, as a drug delivery system that effectively targets and inhibits activated HSCs to treat hepatic fibrosis, holds promise as a potential therapeutic agent against hepatic fibrosis.

Hyaluronic acid as a pulpotomy material in primary molars: an up to 30 months retrospective study

BACKGROUND

The aim of this retrospective study was to determine the long-term clinical and radiographic success of our previous randomized clinical trial and to compare the success of hyaluronic acid, with the widely used formocresol and ferric sulphate agents.

METHODS

This retrospective study is the extension of the 1-year survey of our randomized clinical trial that had compared the effectiveness of a hyaluronic acid pulpotomy over formocresol and ferric sulphate pulpotomies and included clinical and radiographic evaluations with a follow-up period of over 24 months for 44 children who applied to our clinic between May 2019 and September 2019. Long-term clinical and radiographic data were obtained from the periodic files of our department, wherein each tooth's file was examined to identify any clinical and radiographic findings. Descriptive statistics and Pearson's chi-square tests were used to evaluate the data. Statistical significance was considered as p < 0.05.

RESULTS

The clinical and radiographic success rates of the hyaluronic acid, formocresol, and ferric sulphate groups were not statistically different at > 24 months. None of the teeth in the hyaluronic acid group showed any clinical findings at > 24 months.

CONCLUSIONS

Hyaluronic acid pulpotomies exhibited comparable success rates to formocresol and ferric sulphate materials spanning over 24 months examinations. Because of convenient accessibility and applicability of hyaluronic acid, it may be recommended as a promising alternative medicament for pulpotomy treatments of primary molars. However, further long-term follow-up human studies are needed to better understand the effect of hyaluronic acid on the dental pulp of human primary molars.

Characterization of two different alginate-based bioinks and the influence of melanoma growth within

Extrusion-based bioprinting is an established method in biofabrication. Suitable bioinks have fundamentally different compositions and characteristics, which should be examined, in order to find a perfect model system. Here, we investigate the effect of two alginate-based, yet unalike 3D-printed bioinks, pre-crosslinked alginate-dialdehyde gelatin (ADA-GEL) and a mixture of alginate, hyaluronic acid, and gelatin (Alg/HA/Gel), on the melanoma cell line Mel Im and vice versa in terms of stiffness, shrinkage, cellular behavior and colony formation over 15 days. Rheological stiffness measurements revealed two soft gels with similar storage moduli. The cells did not have a significant impact on the overall stiffness, whereas ADA-GEL (2.5/2.5%) was significantly stiffer than Alg/HA/Gel (0.5/0.1/3%). Regarding the shrinkage of printed constructs, cells had a significant influence, especially in ADA-GEL, which has covalent bonds between the oxidized alginate and gelatin. Multi-photon microscopy exhibited proliferation, cell spreading and migration in ADA-GEL with cell-cell and cell-matrix interaction, dissimilarly to Alg/HA/Gel, in which cells formed spherical, encapsulated colonies. Scanning electron microscopy and histology showed degradation and multi-layered growth on ADA-GEL and fewer examples of escaped cells on Alg/HA/Gel. Both gels serve as proliferation bioink for melanoma with more necrosis in deeper Alg/HA/Gel colonies and differences in spreading and matrix interaction. These findings show the importance of proper characterization of the bioinks for different applications.

CD44 and its implication in neoplastic diseases

CD44, a nonkinase single span transmembrane glycoprotein, is a major cell surface receptor for many other extracellular matrix components as well as classic markers of cancer stem cells and immune cells. Through alternative splicing of CD44 gene, CD44 is divided into two isoforms, the standard isoform of CD44 (CD44s) and the variant isoform of CD44 (CD44v). Different isoforms of CD44 participate in regulating various signaling pathways, modulating cancer proliferation, invasion, metastasis, and drug resistance, with its aberrant expression and dysregulation contributing to tumor initiation and progression. However, CD44s and CD44v play overlapping or contradictory roles in tumor initiation and progression, which is not fully understood. Herein, we discuss the present understanding of the functional and structural roles of CD44 in the pathogenic mechanism of multiple cancers. The regulation functions of CD44 in cancers-associated signaling pathways is summarized. Moreover, we provide an overview of the anticancer therapeutic strategies that targeting CD44 and preclinical and clinical trials evaluating the pharmacokinetics, efficacy, and drug-related toxicity about CD44-targeted therapies. This review provides up-to-date information about the roles of CD44 in neoplastic diseases, which may open new perspectives in the field of cancer treatment through targeting CD44.

Controlled-release hydrogel loaded with magnesium-based nanoflowers synergize immunomodulation and cartilage regeneration in tendon-bone healing

Tendon-bone interface injuries pose a significant challenge in tissue regeneration, necessitating innovative approaches. Hydrogels with integrated supportive features and controlled release of therapeutic agents have emerged as promising candidates for the treatment of such injuries. In this study, we aimed to develop a temperature-sensitive composite hydrogel capable of providing sustained release of magnesium ions (Mg2+). We synthesized magnesium-Procyanidin coordinated metal polyphenol nanoparticles (Mg-PC) through a self-assembly process and integrated them into a two-component hydrogel. The hydrogel was composed of dopamine-modified hyaluronic acid (Dop-HA) and F127. To ensure controlled release and mitigate the "burst release" effect of Mg2+, we covalently crosslinked the Mg-PC nanoparticles through coordination bonds with the catechol moiety within the hydrogel. This crosslinking strategy extended the release window of Mg2+ concentrations for up to 56 days. The resulting hydrogel (Mg-PC@Dop-HA/F127) exhibited favorable properties, including injectability, thermosensitivity and shape adaptability, making it suitable for injection and adaptation to irregularly shaped supraspinatus implantation sites. Furthermore, the hydrogel sustained the release of Mg2+ and Procyanidins, which attracted mesenchymal stem and progenitor cells, alleviated inflammation, and promoted macrophage polarization towards the M2 phenotype. Additionally, it enhanced collagen synthesis and mineralization, facilitating the repair of the tendon-bone interface. By incorporating multilevel metal phenolic networks (MPN) to control ion release, these hybridized hydrogels can be customized for various biomedical applications.

The bioengineering application of hyaluronic acid in tissue regeneration and repair

The multifaceted role of hyaluronic acid (HA) across diverse biomedical disciplines underscores its versatility in tissue regeneration and repair. HA hydrogels employ different crosslinking including chemical (chitosan, collagen), photo- initiation (riboflavin, LAP), enzymatic (HRP/H2O2), and physical interactions (hydrogen bonds, metal coordination). In biophysics and biochemistry, HA's signaling pathways, primarily through CD44 and RHAMM receptors, modulate cell behavior (cell migration; internalization of HA), inflammation, and wound healing. Particularly, smaller HA fragments stimulate inflammatory responses through toll-like receptors, impacting macrophages and cytokine expression. HA's implications in oncology highlight its involvement in tumor progression, metastasis, and treatment. Elevated HA in tumor stroma impacts apoptosis resistance and promotes tumor growth, presenting potential therapeutic targets to halt tumor progression. In orthopedics, HA's presence in synovial fluid aids in osteoarthritis management, as its supplementation alleviates pain, enhances synovial fluid's viscoelastic properties, and promotes cartilage integrity. In ophthalmology, HA's application in dry eye syndrome addresses symptoms by moisturizing the eyes, replenishing tear film deficiencies, and facilitating wound healing. Intravitreal injections and hydrogel-based systems offer versatile approaches for drug delivery and vitreous humor replacement. For skin regeneration and wound healing, HA hydrogel dressings exhibit exceptional properties by promoting moist wound healing and facilitating tissue repair. Integration of advanced regenerative tools like stem cells and solubilized amnion membranes into HA-based systems accelerates wound closure and tissue recovery. Overall, HA's unique properties and interactions render it a promising candidate across diverse biomedical domains, showcasing immense potentials in tissue regeneration and therapeutic interventions. Nevertheless, many detailed cellular and molecular mechanisms of HA and its applications remain unexplored and warrant further investigation.

Selective targeting of IRAK1 attenuates low molecular weight hyaluronic acid-induced stemness and non-canonical STAT3 activation in epithelial ovarian cancer

Advanced epithelial ovarian cancer (EOC) survival rates are dishearteningly low, with ~25% surviving beyond 5 years. Evidence suggests that cancer stem cells contribute to acquired chemoresistance and tumor recurrence. Here, we show that IRAK1 is upregulated in EOC tissues, and enhanced expression correlates with poorer overall survival. Moreover, low molecular weight hyaluronic acid, which is abundant in malignant ascites from patients with advanced EOC, induced IRAK1 phosphorylation leading to STAT3 activation and enhanced spheroid formation. Knockdown of IRAK1 impaired tumor growth in peritoneal disease models, and impaired HA-induced spheroid growth and STAT3 phosphorylation. Finally, we determined that TCS2210, a known inducer of neuronal differentiation in mesenchymal stem cells, is a selective inhibitor of IRAK1. TCS2210 significantly inhibited EOC growth in vitro and in vivo both as monotherapy, and in combination with cisplatin. Collectively, these data demonstrate IRAK1 as a druggable target for EOC.

Lactic Acid-Induced Colloidal Microrheology of Synovial Fluids

The presence of colloidal scaffolds composed of proteins and hyaluronic acid engenders unique viscous and elastic properties to the synovial fluid (SF). While the elastic resistance of SF due to the presence of such nanoscale structures provides the load-bearing capacity, the viscous nature enables fluidity of the joints during the movements to minimize the wear and tear of the adjacent muscle, cartilage, or bone tissues. It is well-known that the hypoxic conditions at the bone joints often increase the lactic acid (LA) concentration due to the occurrence of excess anaerobic respiration during either hyperactivity or arthritic conditions. The present study uncovers that in such a scenario, beyond a critical loading of LA, the colloidal nanoscaffolds of SF break down to precipitate higher molecular weight (MW) proteins and hyaluronic acid (HA). Subsequently, the viscosity and elasticity of SF reduce drastically to manifest a fluid that has reduced load bearing and wear and tear resistance capacity. Interestingly, the study also suggests that a heathy SF is a viscoelastic fluid with a mild Hookean elasticity and non-Newtonian fluidity, which eventually transforms into a viscous watery liquid in the presence of a higher loading of LA. We employ this knowledge to biosynthesize an artificial SF that emulates the characteristics of the real one. Remarkably, the spatiotemporal microscopic images uncover that even for the artificial SF, a dynamic cross-linking of the high MW proteins and HA takes place before precipitating out of the same from the artificial SF matrix, emulating the real one. Control experiments suggest that this phenomenon is absent in the case when LA is mixed with either pure HA or proteins. The experiments unfold the specific role of LA in the destruction of colloidal nanoscaffolds of synovia, which is an extremely important requirement for the biosynthesis and translation of artificial synovial fluid.

Research advances in Zein-based nano-delivery systems

Zein is the main vegetable protein from maize. In recent years, Zein has been widely used in pharmaceutical, agriculture, food, environmental protection, and other fields because it has excellent biocompatibility and biosafety. However, there is still a lack of systematic review and research on Zein-based nano-delivery systems. This paper systematically reviews preparation and modification methods of Zein-based nano-delivery systems, based on the basic properties of Zein. It discusses the preparation of Zein nanoparticles and the influencing factors in detail, as well as analyzing the advantages and disadvantages of different preparation methods and summarizing modification methods of Zein nanoparticles. This study provides a new idea for the research of Zein-based nano-delivery system and promotes its application.

Hyaluronan in mesenchymal stromal cell lineage differentiation from human pluripotent stem cells: application in serum free culture

BACKGROUND

Hyaluronan (HA) is an extracellular glycosaminoglycan polysaccharide with widespread roles throughout development and in healthy and neoplastic tissues. In pluripotent stem cell culture it can support both stem cell renewal and differentiation. However, responses to HA in culture are influenced by interaction with a range of cognate factors and receptors including components of blood serum supplements, which alter results. These may contribute to variation in cell batch production yield and phenotype as well as heighten the risks of adventitious pathogen transmission in the course of cell processing for therapeutic applications. MAIN: Here we characterise differentiation of a human embryo/pluripotent stem cell derived Mesenchymal Stromal Cell (hESC/PSC-MSC)-like cell population by culture on a planar surface coated with HA in serum-free media qualified for cell production for therapy. Resulting cells met minimum criteria of the International Society for Cellular Therapy for identification as MSC by expression of. CD90, CD73, CD105, and lack of expression for CD34, CD45, CD14 and HLA-II. They were positive for other MSC associated markers (i.e.CD166, CD56, CD44, HLA 1-A) whilst negative for others (e.g. CD271, CD71, CD146). In vitro co-culture assessment of MSC associated functionality confirmed support of growth of hematopoietic progenitors and inhibition of mitogen activated proliferation of lymphocytes from umbilical cord and adult peripheral blood mononuclear cells, respectively. Co-culture with immortalized THP-1 monocyte derived macrophages (Mɸ) concurrently stimulated with lipopolysaccharide as a pro-inflammatory stimulus, resulted in a dose dependent increase in pro-inflammatory IL6 but negligible effect on TNFα. To further investigate these functionalities, a bulk cell RNA sequence comparison with adult human bone marrow derived MSC and hESC substantiated a distinctive genetic signature more proximate to the former.

CONCLUSION

Cultivation of human pluripotent stem cells on a planar substrate of HA in serum-free culture media systems is sufficient to yield a distinctive developmental mesenchymal stromal cell lineage with potential to modify the function of haematopoietic lineages in therapeutic applications.

Isolation, Characterization, Genome Annotation, and Evaluation of Hyaluronidase Inhibitory Activity in Secondary Metabolites of Brevibacillus sp. JNUCC 41: A Comprehensive Analysis through Molecular Docking and Molecular Dynamics Simulation

Brevibacillus sp. JNUCC 41, characterized as a plant-growth-promoting rhizobacterium (PGPR), actively participates in lipid metabolism and biocontrol based on gene analysis. This study aimed to investigate the crucial secondary metabolites in biological metabolism; fermentation, extraction, and isolation were performed, revealing that methyl indole-3-acetate showed the best hyaluronidase (HAase) inhibitory activity (IC50: 343.9 μM). Molecular docking results further revealed that the compound forms hydrogen bonds with the residues Tyr-75 and Tyr-247 of HAase (binding energy: -6.4 kcal/mol). Molecular dynamics (MD) simulations demonstrated that the compound predominantly binds to HAase via hydrogen bonding (MM-PBSA binding energy: -24.9 kcal/mol) and exhibits good stability. The residues Tyr-247 and Tyr-202, pivotal for binding in docking, were also confirmed via MD simulations. This study suggests that methyl indole-3-acetate holds potential applications in anti-inflammatory and anti-aging treatments.

CD44: A New Prognostic Marker in Colorectal Cancer?

Cluster of differentiation 44 (CD44) is a non-kinase cell surface glycoprotein. It is overexpressed in several cell types, including cancer stem cells (CSCs). Cells overexpressing CD44 exhibit several CSC traits, such as self-renewal, epithelial-mesenchymal transition (EMT) capability, and resistance to chemo- and radiotherapy. The role of CD44 in maintaining stemness and the CSC function in tumor progression is accomplished by binding to its main ligand, hyaluronan (HA). The HA-CD44 complex activates several signaling pathways that lead to cell proliferation, adhesion, migration, and invasion. The CD44 gene regularly undergoes alternative splicing, resulting in the standard (CD44s) and variant (CD44v) isoforms. The different functional roles of CD44s and specific CD44v isoforms still need to be fully understood. The clinicopathological impact of CD44 and its isoforms in promoting tumorigenesis suggests that CD44 could be a molecular target for cancer therapy. Furthermore, the recent association observed between CD44 and KRAS-dependent carcinomas and the potential correlations between CD44 and tumor mutational burden (TMB) and microsatellite instability (MSI) open new research scenarios for developing new strategies in cancer treatment. This review summarises current research regarding the different CD44 isoform structures, their roles, and functions in supporting tumorigenesis and discusses its therapeutic implications.

Gelatin Methacryloyl (GelMA)-Based Biomaterial Inks: Process Science for 3D/4D Printing and Current Status

Tissue engineering for injured tissue replacement and regeneration has been a subject of investigation over the last 30 years, and there has been considerable interest in using additive manufacturing to achieve these goals. Despite such efforts, many key questions remain unanswered, particularly in the area of biomaterial selection for these applications as well as quantitative understanding of the process science. The strategic utilization of biological macromolecules provides a versatile approach to meet diverse requirements in 3D printing, such as printability, buildability, and biocompatibility. These molecules play a pivotal role in both physical and chemical cross-linking processes throughout the biofabrication, contributing significantly to the overall success of the 3D printing process. Among the several bioprintable materials, gelatin methacryloyl (GelMA) has been widely utilized for diverse tissue engineering applications, with some degree of success. In this context, this review will discuss the key bioengineering approaches to identify the gelation and cross-linking strategies that are appropriate to control the rheology, printability, and buildability of biomaterial inks. This review will focus on the GelMA as the structural (scaffold) biomaterial for different tissues and as a potential carrier vehicle for the transport of living cells as well as their maintenance and viability in the physiological system. Recognizing the importance of printability toward shape fidelity and biophysical properties, a major focus in this review has been to discuss the qualitative and quantitative impact of the key factors, including microrheological, viscoelastic, gelation, shear thinning properties of biomaterial inks, and printing parameters, in particular, reference to 3D extrusion printing of GelMA-based biomaterial inks. Specifically, we emphasize the different possibilities to regulate mechanical, swelling, biodegradation, and cellular functionalities of GelMA-based bio(material) inks, by hybridization techniques, including different synthetic and natural biopolymers, inorganic nanofillers, and microcarriers. At the close, the potential possibility of the integration of experimental data sets and artificial intelligence/machine learning approaches is emphasized to predict the printability, shape fidelity, or biophysical properties of GelMA bio(material) inks for clinically relevant tissues.

Hyaluronic acid from bluefin tuna by-product: Structural analysis and pharmacological activities

The fishing and aquaculture industries generate a huge amount of waste during processing and preservation operations, especially those of tuna. Recovering these by-products is a major economic and environmental challenge for manufacturers seeking to produce new active biomolecules of interest. A new hyaluronic acid was extracted from bluefin tuna's vitreous humour to assess its antioxidant and pharmacological activities. The characterization by infrared spectroscopy (FT-IR), nuclear magnetic resonance ((1D1H) and 2D (1H COSY, 1H/13C HSQC)) and size exclusion chromatography (SEC/MALS/DRI/VD) revealed that the extracted polysaccharide was a hyaluronic acid with high uronic acid content (55.8 %) and a weight average molecular weight of 888 kDa. This polymer possesses significant anti-radical activity and ferrous chelating capacity. In addition, pharmacological evaluation of its anti-inflammatory and analgesic potential, using preclinical models, in comparison with reference drugs (Dexamethasone, diclofenac, and acetylsalicylate of lysine), revealed promising anti-inflammatory activity as well as interesting peripheral and central antinociceptive activity. Therefore, our new hyaluronic acid compound may therefore serve as a potential drug candidate for the treatment of pain sensation and inflammation of various pathological origins.

Anchoring of hyaluronan glycocalyx to CD44 reduces sensitivity of HER2-positive gastric cancer cells to trastuzumab

Trastuzumab is widely used in human epidermal growth factor receptor 2 (HER2)-positive gastric cancer (GC) therapy, but ubiquitous resistance limits its clinical application. In this study, we first showed that CD44 antigen is a significant predictor of overall survival for patients with HER2-positive GC. Next, we found that CD44 could be co-immunoprecipitated and co-localized with HER2 on the membrane of GC cells. By analyzing the interaction between CD44 and HER2, we identified that CD44 could upregulate HER2 protein by inhibiting its proteasome degradation. Notably, the overexpression of CD44 could decrease the sensitivity of HER2-positive GC cells to trastuzumab. Further mechanistic study showed that CD44 upregulation could induce its ligand, hyaluronan (HA), to deposit on the cancer cell surface, resulting in covering up the binding sites of trastuzumab to HER2. Removing the HA glycocalyx restored sensitivity of the cells to trastuzumab. Collectively, our findings suggested a role for CD44 in regulating trastuzumab sensitivity and provided novel insights into HER2-targeted therapy.

Role of endothelial hyaluronan in peritoneal membrane transport and disease conditions during peritoneal dialysis

Peritoneal membrane dysfunction in peritoneal dialysis (PD) is primarily attributed to angiogenesis; however, the integrity of vascular endothelial cells can affect peritoneal permeability. Hyaluronan, a component of the endothelial glycocalyx, is reportedly involved in preventing proteinuria in the normal glomerulus. One hypothesis suggests that development of encapsulating peritoneal sclerosis (EPS) is triggered by protein leakage due to vascular endothelial injury. We therefore investigated the effect of hyaluronan in the glycocalyx on peritoneal permeability and disease conditions. After hyaluronidase-mediated degradation of hyaluronan on the endothelial cells of mice, macromolecules, including albumin and β2 microglobulin, leaked into the dialysate. However, peritoneal transport of small solute molecules was not affected. Pathologically, hyaluronan expression was diminished; however, expression of vascular endothelial cadherin and heparan sulfate, a core protein of the glycocalyx, was preserved. Hyaluronan expression on endothelial cells was studied using 254 human peritoneal membrane samples. Hyaluronan expression decreased in patients undergoing long-term PD treatment and EPS patients treated with conventional solutions. Furthermore, the extent of hyaluronan loss correlated with the severity of vasculopathy. Hyaluronan on endothelial cells is involved in the peritoneal transport of macromolecules. Treatment strategies that preserve hyaluronan in the glycocalyx could prevent the leakage of macromolecules and subsequent related complications.

Prospects and challenges of CAR-T cell therapy combined with ICIs

Immune checkpoint molecules are a group of molecules expressed on the surface of immune cells that primarily regulate their immune homeostasis. Chimeric antigen receptor (CAR) T cell therapy is an immunotherapeutic technology that realizes tumor-targeted killing by constructing synthetic T cells expressing specific antigens through biotechnology. Currently, CAR-T cell therapy has achieved good efficacy in non-solid tumors, but its treatment of solid tumors has not yielded the desired results. Immune checkpoint inhibitors (ICIs) combined with CAR-T cell therapy is a novel combination therapy with high expectations to defeat solid tumors. This review addresses the challenges and expectations of this combination therapy in the treatment of solid tumors.

An oncolytic vaccinia virus encoding hyaluronidase reshapes the extracellular matrix to enhance cancer chemotherapy and immunotherapy

BACKGROUND

The redundant extracellular matrix (ECM) within tumor microenvironment (TME) such as hyaluronic acid (HA) often impairs intratumoral dissemination of antitumor drugs. Oncolytic viruses (OVs) are being studied extensively for cancer therapy either alone or in conjunction with chemotherapy and immunotherapy. Here, we designed a novel recombinant vaccinia virus encoding a soluble version of hyaluronidase Hyal1 (OVV-Hyal1) to degrade the HA and investigated its antitumor effects in combination with chemo drugs, polypeptide, immune cells, and antibodies.

METHODS

We constructed a recombinant oncolytic vaccinia virus encoding the hyaluronidase, and investigated its function in remodeling the ECM of the TME, the antitumor efficacy both in vitro and in several murine solid tumors either alone, or in combination with chemo drugs including doxorubicin and gemcitabine, with polypeptide liraglutide, with immune therapeutics such as PD-L1/PD-1 blockade, CD47 antibody, and with CAR-T cells.

RESULTS

Compared with control OVV, intratumoral injection of OVV-Hyal1 showed superior antitumor efficacies in a series of mouse subcutaneous tumor models. Moreover, HA degradation by OVV-Hyal1 resulted in increased intratumoral dissemination of chemo drugs, infiltration of T cells, NK cells, macrophages, and activation of CD8+ T cells. When OVV-Hyal1 was combined with some antitumor therapeutics, for example, doxorubicin, gemcitabine, liraglutide, anti-PD-1, anti-CD47 blockade, or CAR-T cells, more profound therapeutic outcomes were obtained.

CONCLUSIONS

OVV-Hyal1 effectively degrades HA to reshape the TME, therefore overcoming some major hurdles in current cancer therapy, such as limited OVs spread, unfavored dissemination of chemo drugs, polypeptides, antibodies, and insufficient infiltration of effector immune cells. OVV-Hyal1 holds the promise to improve the antitumor outcomes of current cancer therapeutics.

Hyaluronic acid turnover controls the severity of cerebral cavernous malformations in bioengineered human micro-vessels

Cerebral cavernous malformations (CCMs) are vascular lesions that predominantly form in blood vessels of the central nervous system upon loss of the CCM multimeric protein complex. The endothelial cells within CCM lesions are characterized by overactive MEKK3 kinase and KLF2/4 transcription factor signaling, leading to pathological changes such as increased endothelial cell spreading and reduced junctional integrity. Concomitant to aberrant endothelial cell signaling, non-autonomous signals from the extracellular matrix (ECM) have also been implicated in CCM lesion growth and these factors might explain why CCM lesions mainly develop in the central nervous system. Here, we adapted a three-dimensional microfluidic system to examine CCM1 deficient human micro-vessels in distinctive extracellular matrices. We validate that pathological hallmarks are maintained in this model. We further show that key genes responsible for homeostasis of hyaluronic acid, a major extracellular matrix component of the central nervous system, are dysregulated in CCM. Supplementing the matrix in our model with distinct forms of hyaluronic acid inhibits pathological cell spreading and rescues barrier function. Hyaluronic acid acts by dampening cell-matrix adhesion signaling in CCM, either downstream or in parallel of KLF2/4. This study provides a proof-of-principle that ECM embedded 3D microfluidic models are ideally suited to identify how changes in ECM structure and signaling impact vascular malformations.

UDP-glucose dehydrogenase supports autophagy-deficient PDAC growth via increasing hyaluronic acid biosynthesis

Autophagy is an essential degradation and recycling process that maintains cellular homeostasis during stress or nutrient deprivation. However, certain types of tumors such as pancreatic cancers can circumvent autophagy inhibition to sustain growth. The mechanism that autophagy-deficient pancreatic ductal adenocarcinoma (PDAC) uses to grow under nutrient deprivation is poorly understood. Our data show that nutrient deprivation in PDAC results in UDP-glucose dehydrogenase (UGDH) degradation, which is dependent on autophagic cargo receptor sequestosome 1 (p62). Moreover, we demonstrate that accumulated UGDH is indispensable for autophagy-deficient PDAC cells proliferation by promoting hyaluronic acid (HA) synthesis upon energy deprivation. Using an orthotopic mouse model of PDAC, we find that inhibition of HA synthesis by targeting UGDH in PDAC reduces tumor weight. Thus, the combined inhibition of HA and autophagy might be an attractive strategy for PDAC treatment.

Hyaluronic Acid Unveiled: Exploring the Nanomechanics and Water Retention Properties at the Single-Molecule Level

Hyaluronic acid (HA), a vital glycosaminoglycan in living organisms, possesses remarkable mechanical and viscoelastic properties that have garnered significant attention in therapeutic, biomedical, and cosmetic applications. However, a comprehensive picture of the physicochemical and biocharacterization of HA at the single-molecule level remains elusive. In this work, atomic force microscopy (AFM)-based single-molecule force spectroscopy (SMFS) and molecular dynamics (MD) simulation were used to investigate the nanomechanics and water retention properties of HA at the single-molecule level. The present study aims to unravel the intricate details of the influence of molecular structure on HA behavior and shed light on its unique attributes. According to the force measurements, the energy used to stretch a HA chain in water is 8.45 kJ/mol, significantly surpassing that of Curdlan (3.45 kJ/mol) and chitin (2.23 kJ/mol), both of which possess molecular structures partially similar to that of HA. Intriguingly, the strength of the intrachain interaction of HA (5.54 kJ/mol) was considerably weaker compared to Curdlan (11.06 kJ/mol) and chitin (or cellulose, 10.76 kJ/mol). This result indicates that HA exhibits a preference for interacting with water rather than with itself, thereby showing enhanced water affinity. Moreover, the force measurements demonstrated that changing the glycosidic bond from β-(1-3) (Curdlan) or β-(1-4) (chitin or cellulose) to β-(1-3) + β-(1-4) (HA) resulted in polysaccharides displaying improved water affinity and more extended conformation. These conclusions were further verified by molecular dynamics (MD) simulations. Overall, our work sheds new light on the nanomechanics and water retention properties of HA at the single-molecule level, offering valuable insights for future research in this field.

Hyaluronan-arginine enhanced and dynamic interaction emerges from distinctive molecular signature due to electrostatics and side-chain specificity

Hyaluronan is a natural carbohydrate polymer with a negative charge that fosters gel-like conditions crucial for its cellular functions and industrial applications. As a recognized ligand for proteins, understanding their mutual interactions provides solid ground to tune hyaluronan's gel properties using biocompatible peptides. This work employs NMR and molecular dynamics simulations to identify molecular motifs relevant to hyaluronan-peptide interactions using arginine, lysine, and glycine oligopeptides. Arginine-rich peptides exhibit the strongest binding to hyaluronan according to chemical shift perturbation measurements, followed distantly by the similarly charged lysine. This difference highlights the significance of electrostatics and the peculiarities of the guanidinium side chain in arginine, capable of non-polar interactions that further stabilize the binding. Additional nuclear Overhauser effect measurements do not show stable interaction partners, precluding strong and well-defined complexes. Finally, molecular simulations support our findings and show an extended but significant interaction region, especially for arginine, responsible for the observed enhanced binding, which can also promote cross-linking of hyaluronan polymers. Our findings pave the way for optimizing biocompatible peptides to alter hyaluronan gels' properties efficiently and also explain why hyaluronan-protein interaction typically involves positively charged arginine-rich regions also capable of forming hydrogen bonds and non-polar interactions.

Organ Frame Elements or Free Intercellular Gel-Like Matrix as Necessary Conditions for Building Organ Structures during Regeneration

Over the past decades, an unimaginably large number of attempts have been made to restore the structure of mammalian organs after injury by introducing stem cells into them. However, this procedure does not lead to full recovery. At the same time, it is known that complete regeneration (restitution without fibrosis) is possible in organs with proliferating parenchymal cells. An analysis of such models allows to conclude that the most important condition for the repair of histological structures of an organ (in the presence of stem cells) is preservation of the collagen frame structures in it, which serve as "guide rails" for proliferating and differentiating cells. An alternative condition for complete reconstruction of organ structures is the presence of a free "morphogenetic space" containing a gel-like matrix of the embryonic-type connective tissue, which exists during embryonal development of organs in mammals or during complete regeneration in amphibians. Approaches aimed at preserving frame structures or creating a "morphogenetic space" could radically improve the results of organ regeneration using both local and exogenous stem cells.

The Current State of Extracellular Matrix Therapy for Ischemic Heart Disease

The extracellular matrix (ECM) is a three-dimensional, acellular network of diverse structural and nonstructural proteins embedded within a gel-like ground substance composed of glycosaminoglycans and proteoglycans. The ECM serves numerous roles that vary according to the tissue in which it is situated. In the myocardium, the ECM acts as a collagen-based scaffold that mediates the transmission of contractile signals, provides means for paracrine signaling, and maintains nutritional and immunologic homeostasis. Given this spectrum, it is unsurprising that both the composition and role of the ECM has been found to be modulated in the context of cardiac pathology. Myocardial infarction (MI) provides a familiar example of this; the ECM changes in a way that is characteristic of the progressive phases of post-infarction healing. In recent years, this involvement in infarct pathophysiology has prompted a search for therapeutic targets: if ECM components facilitate healing, then their manipulation may accelerate recovery, or even reverse pre-existing damage. This possibility has been the subject of numerous efforts involving the integration of ECM-based therapies, either derived directly from biologic sources or bioengineered sources, into models of myocardial disease. In this paper, we provide a thorough review of the published literature on the use of the ECM as a novel therapy for ischemic heart disease, with a focus on biologically derived models, of both the whole ECM and the components thereof.

Unraveling and Harnessing the Immune Response at the Cell-Biomaterial Interface for Tissue Engineering Purposes

Biomaterials are defined as "engineered materials" and include a range of natural and synthetic products, designed for their introduction into and interaction with living tissues. Biomaterials are considered prominent tools in regenerative medicine that support the restoration of tissue defects and retain physiologic functionality. Although commonly used in the medical field, these constructs are inherently foreign toward the host and induce an immune response at the material-tissue interface, defined as the foreign body response (FBR). A strong connection between the foreign body response and tissue regeneration is suggested, in which an appropriate amount of immune response and macrophage polarization is necessary to trigger autologous tissue formation. Recent developments in this field have led to the characterization of immunomodulatory traits that optimizes bioactivity, the integration of biomaterials and determines the fate of tissue regeneration. This review addresses a variety of aspects that are involved in steering the inflammatory response, including immune cell interactions, physical characteristics, biochemical cues, and metabolomics. Harnessing the advancing knowledge of the FBR allows for the optimization of biomaterial-based implants, aiming to prevent damage of the implant, improve natural regeneration, and provide the tools for an efficient and successful in vivo implantation.

Triply Enhanced Immunotherapy via Dual Glycan Reforming Integrated with Perforation

The enhancement of immunotherapy is an emerging direction to develop highly effective and practical cancer therapeutic methods. Here a triply enhanced immunotherapy drug (TEID) is designed for ingeniously integrating in situ dual glycan reforming with perforation on cell membrane. The TEID is composed of galactose and neuraminidase conjugated streptolysin O (SLO-Gal and SLO-NEU), which are encapsulated in a hyaluronic acid (HA) shell for targeted recognition to tumor tissue via cell surface CD44. After targeted delivery and HAase-mediated degradation in the tumor region, the TEID releases SLO-Gal and SLO-NEU, which can easily anchor Gal and NEU on the tumor cell membrane via the perforation of SLO to perform dual glycan reforming for the introduction of Gal and the cleavage of sialic acid. The former can activate immune cells to secret cytokines for immune-killing, and the latter can weaken the immune inhibition to improve the immunotherapeutic efficacy. Meanwhile, the perforation of SLO can promote the delivery of cytokines into the tumor cells to further enhance the efficacy. The designed triply enhanced immunotherapy strategy opens a significant and promising route to promote clinical immunotherapy of cancer.

Reprogramming of VEGF-mediated extracellular matrix changes through autocrine signaling

Vascular endothelial growth factor (VEGF) plays key roles in angiogenesis, vasculogenesis, and wound healing. In cancers, including triple negative breast cancer (TNBC), VEGF has been associated with increased invasion and metastasis, processes that require cancer cells to traverse through the extracellular matrix (ECM) and establish angiogenesis at distant sites. To further understand the role of VEGF in modifying the ECM, we characterized VEGF-mediated changes in the ECM of tumors derived from TNBC MDA-MB-231 cells engineered to overexpress VEGF. We established that increased VEGF expression by these cells resulted in tumors with reduced collagen 1 (Col1) fibers, fibronectin, and hyaluronan. Molecular characterization of tumors identified an increase of MMP1, uPAR, and LOX, and a decrease of MMP2, and ADAMTS1. α-SMA, a marker of cancer associated fibroblasts (CAFs), increased, and FAP-α, a marker of a subset of CAFs associated with immune suppression, decreased with VEGF overexpression. Analysis of human data from The Cancer Genome Atlas Program confirmed mRNA differences for several molecules when comparing TNBC with high and low VEGF expression. We additionally characterized enzymatic changes induced by VEGF overexpression in three different cancer cell lines that clearly identified autocrine-mediated changes, specifically uPAR, in these enzymes. Unlike the increase of Col1 fibers and fibronectin mediated by VEGF during wound healing, in the TNBC model, VEGF significantly reduced key protein components of the ECM. These results further expand our understanding of the role of VEGF in cancer progression and identify potential ECM-related targets to disrupt this progression.

A self-gelling hydrogel based on thiolated hyaluronic acid for three-dimensional culture of ovine preantral follicles

Three-dimensional (3D) ovarian follicle culture offers a promising option for fertility preservation in patients who cannot receive ovarian tissue transplantation. Our research evaluated the potential of a hydrogel composed of thiolated hyaluronic acid (HA-SH) for ovine preantral follicle development compared to routinely used alginate hydrogel (ALG). Synthesized via a carbodiimide reaction, HA-SH facilitated a self-crosslinking hydrogel through disulfide bond formation. Ovine preantral follicles (200-300 μm) retrieved through mechanical and enzymatic methods were encapsulated individually in either ALG or HA-SH hydrogels. Although both hydrogels adequately supported follicle survival, 3D integrity, and antrum formation over a 17-day in vitro culture, follicle growth was significantly higher within the HA-SH hydrogel. Gene expression analysis underscored that some folliculogenesis-related genes (ZP3, BMP7, and GJA1) and a steroidogenic gene (CYP19A1) demonstrated higher expression levels in HA-SH encapsulated follicles versus ALG. Collectively, our findings advocate for HA-SH hydrogel as a potent biomaterial for in vitro follicle cultures, attributing its efficacy to facile gelation, bio-responsiveness, and superior support for follicle growth.

Alginate/hyaluronic acid-based systems as a new generation of wound dressings: A review

Skin is the largest organ of the human body, which acts as a protective barrier against pathogens. Therefore, a lot of research has been carried out on wound care and healing. Creating an ideal environment for wound healing and optimizing the local and systemic conditions of the patient play critical roles in successful wound care. Many products have been developed for improving the wound environment and providing a protected and moist area for fast healing. However, there is still high demand for new systems with high efficiency. The first generation of wound dressings merely covered the wound, while the subsequent/last generations covered it and aided in healing it in different ways. In modern wound dressings, the kind of used materials and their complexity play a crucial role in the healing process. These new systems support wound healing by lowering inflammation, exudate, slough, and bacteria. This study addresses a review of alginate/hyaluronic acid-based wound dressings developed so far as well as binary and ternary systems and their role in wound healing. Our review corroborates that these systems can open up a new horizon for wounds that do not respond to usual treatments and have a long curing period.

From molecules to behavior: Implications for perineuronal net remodeling in learning and memory

Perineuronal nets (PNNs) are condensed extracellular matrix (ECM) structures found throughout the central nervous system that regulate plasticity. They consist of a heterogeneous mix of ECM components that form lattice-like structures enwrapping the cell body and proximal dendrites of particular neurons. During development, accumulating research has shown that the closure of various critical periods of plasticity is strongly linked to experience-driven PNN formation and maturation. PNNs provide an interface for synaptic contacts within the holes of the structure, generally promoting synaptic stabilization and restricting the formation of new synaptic connections in the adult brain. In this way, they impact both synaptic structure and function, ultimately influencing higher cognitive processes. PNNs are highly plastic structures, changing their composition and distribution throughout life and in response to various experiences and memory disorders, thus serving as a substrate for experience- and disease-dependent cognitive function. In this review, we delve into the proposed mechanisms by which PNNs shape plasticity and memory function, highlighting the potential impact of their structural components, overall architecture, and dynamic remodeling on functional outcomes in health and disease.

Inflammation-Associated Cytotoxic Agents in Tumorigenesis

Chronic inflammatory processes are related to all stages of tumorigenesis. As inflammation is closely associated with the activation and release of different cytotoxic agents, the interplay between cytotoxic agents and antagonizing principles is highlighted in this review to address the question of how tumor cells overcome the enhanced values of cytotoxic agents in tumors. In tumor cells, the enhanced formation of mitochondrial-derived reactive species and elevated values of iron ions and free heme are antagonized by an overexpression of enzymes and proteins, contributing to the antioxidative defense and maintenance of redox homeostasis. Through these mechanisms, tumor cells can even survive additional stress caused by radio- and chemotherapy. Through the secretion of active agents from tumor cells, immune cells are suppressed in the tumor microenvironment and an enhanced formation of extracellular matrix components is induced. Different oxidant- and protease-based cytotoxic agents are involved in tumor-mediated immunosuppression, tumor growth, tumor cell invasion, and metastasis. Considering the special metabolic conditions in tumors, the main focus here was directed on the disturbed balance between the cytotoxic agents and protective mechanisms in late-stage tumors. This knowledge is mandatory for the implementation of novel anti-cancerous therapeutic approaches.

Hybrid Polymer-Inorganic Materials with Hyaluronic Acid as Controlled Antibiotic Release Systems

In recent years, significant developments have taken place in scientific fields such as tissue and materials engineering, which allow for the development of new, intelligent biomaterials. An example of such biomaterials is drug delivery systems that release the active substance directly at the site where the therapeutic effect is required. In this research, polymeric materials and ceramic-polymer composites were developed as carriers for the antibiotic clindamycin. The preparation and characterization of biomaterials based on hyaluronic acid, collagen, and nano brushite obtained using the photocrosslinking technique under UV (ultraviolet) light are described. Physical and chemical analyses of the materials obtained were carried out using Fourier transform infrared spectroscopy (FT-IR) and optical microscopy. The sorption capacities were determined and subjected to in vitro incubation in simulated biological environments such as Ringer's solution, simulated body fluid (SBF), phosphate-buffered saline (PBS), and distilled water. The antibiotic release rate was also measured. The study confirmed higher swelling capacity for materials with no addition of a ceramic phase, thus it can be concluded that brushite inhibits the penetration of the liquid medium into the interior of the samples, leading to faster absorption of the liquid medium. In addition, incubation tests confirmed preliminary biocompatibility. No drastic changes in pH values were observed, which suggests that the materials are stable under these conditions. The release rate of the antibiotic from the biomaterial into the incubation medium was determined using high-pressure liquid chromatography (HPLC). The concentration of the antibiotic in the incubation fluid increased steadily following a 14-day incubation in PBS, indicating continuous antibiotic release. Based on the results, it can be concluded that the developed polymeric material demonstrates potential for use as a carrier for the active substance.

Controllable and biocompatible 3D bioprinting technology for microorganisms: Fundamental, environmental applications and challenges

3D bioprinting is a new 3D manufacturing technology, that can be used to accurately distribute and load microorganisms to form microbial active materials with multiple complex functions. Based on the 3D printing of human cells in tissue engineering, 3D bioprinting technology has been developed. Although 3D bioprinting technology is still immature, it shows great potential in the environmental field. Due to the precise programming control and multi-printing pathway, 3D bioprinting technology provides a high-throughput method based on micron-level patterning for a wide range of environmental microbiological engineering applications, which makes it an on-demand, multi-functional manufacturing technology. To date, 3D bioprinting technology has been employed in microbial fuel cells, biofilm material preparation, microbial catalysts and 4D bioprinting with time dimension functions. Nevertheless, current 3D bioprinting technology faces technical challenges in improving the mechanical properties of materials, developing specific bioinks to adapt to different strains, and exploring 4D bioprinting for intelligent applications. Hence, this review systematically analyzes the basic technical principles of 3D bioprinting, bioinks materials and their applications in the environmental field, and proposes the challenges and future prospects of 3D bioprinting in the environmental field. Combined with the current development of microbial enhancement technology in the environmental field, 3D bioprinting will be developed into an enabling platform for multifunctional microorganisms and facilitate greater control of in situ directional reactions.

A fetal wound healing program after intrauterine bile duct injury may contribute to biliary atresia

BACKGROUND & AIMS

Biliary atresia (BA) is an obstructive cholangiopathy that initially affects the extrahepatic bile ducts (EHBDs) of neonates. The etiology is uncertain, but evidence points to a prenatal cause. Fetal tissues have increased levels of hyaluronic acid (HA), which plays an integral role in fetal wound healing. The objective of this study was to determine whether a program of fetal wound healing is part of the response to fetal EHBD injury.

METHODS

Mouse, rat, sheep, and human EHBD samples were studied at different developmental time points. Models included a fetal sheep model of prenatal hypoxia, human BA EHBD remnants and liver samples taken at the time of the Kasai procedure, EHBDs isolated from neonatal rats and mice, and spheroids and other models generated from primary neonatal mouse cholangiocytes.

RESULTS

A wide layer of high molecular weight HA encircling the lumen was characteristic of the normal perinatal but not adult EHBD. This layer, which was surrounded by collagen, expanded in injured ducts in parallel with extensive peribiliary gland hyperplasia, increased mucus production and elevated serum bilirubin levels. BA EHBD remnants similarly showed increased HA centered around ductular structures compared with age-appropriate controls. High molecular weight HA typical of the fetal/neonatal ducts caused increased cholangiocyte spheroid growth, whereas low molecular weight HA induced abnormal epithelial morphology; low molecular weight HA caused matrix swelling in a bile duct-on-a-chip device.

CONCLUSION

The fetal/neonatal EHBD, including in human EHBD remnants from Kasai surgeries, demonstrated an injury response with prolonged high levels of HA typical of fetal wound healing. The expanded peri-luminal HA layer may swell and lead to elevated bilirubin levels and obstruction of the EHBD.

IMPACT AND IMPLICATIONS

Biliary atresia is a pediatric cholangiopathy associated with high morbidity and mortality rates; although multiple etiologies have been proposed, the fetal response to bile duct damage is largely unknown. This study explores the fetal pathogenesis after extrahepatic bile duct damage, thereby opening a completely new avenue to study therapeutic targets in the context of biliary atresia.

Hyaluronan Metabolism in Urologic Cancers

Hyaluronan (HA) is one of the major components of the extracellular matrix in tumor tissue. Recent reports have made it clear that the balance of HA synthesis and degradation is critical for tumor progression. HA is synthesized on the cytoplasmic surface of the plasma membrane by hyaluronan synthases (HAS) and extruded into the extracellular space. Excessive HA production in cancer is associated with enhanced HA degradation in the tumor microenvironment, leading to the accumulation of HA fragments with small molecular weight. These perturbations in both HA synthesis and degradation may play important roles in tumor progression. Recently, it has become increasingly clear that small HA fragments can induce a variety of biological events, such as angiogenesis, cancer-promoting inflammation, and tumor-associated immune suppression. Progression of urologic malignancies, particularly of prostate and bladder cancers, as well as of certain types of kidney cancer show markedly perturbed metabolism of tumor-associated HA. This review highlights the recent research findings regarding HA metabolism in tumor microenvironments with a special focus on urologic cancers. It also will discuss the potential implications of these findings for the development of novel therapeutic interventions for the treatment of prostate, bladder, and kidney cancers.

Development of hyaluronic acid-silica composites via in situ precipitation for improved penetration efficiency in fast-dissolving microneedle systems

Fast-dissolving microneedles (DMNs) hold significant promise for transdermal drug delivery, offering improved patient compliance, biocompatibility, and functional adaptability for various therapeutic purposes. However, the mechanical strength of the biodegradable polymers used in DMNs often proves insufficient for effective penetration into human skin, especially under high humidity conditions. While many composite strategies have been developed to reinforce polymer-based DMNs, simple mixing of the reinforcements with polymers often results in ineffective penetration due to inhomogeneous dispersion of the reinforcements and the formation of undesired micropores. In response to this challenge, this study aimed to enhance the mechanical performance of hyaluronic acid (HA)-based microneedles (MNs), one of the most commonly used DMN systems. We introduced in situ precipitation of silica nanoparticles (Si) into the HA matrix in conjunction with conventional micromolding. The precipitated silica nanoparticles were uniformly distributed, forming an interconnected network within the HA matrix. Experimental results demonstrated that the mechanical properties of the HA-Si composite MNs with up to 20 vol% Si significantly improved, leading to higher penetration efficiency compared to pure HA MNs, while maintaining structural integrity without any critical defects. The composite MNs also showed reduced degradation rates and preserved their drug delivery capabilities and biocompatibility. Thus, the developed HA-Si composite MNs present a promising solution for efficient transdermal drug delivery and address the mechanical limitations inherent in DMN systems. STATEMENT OF SIGNIFICANCE: HA-Si composite dissolving microneedle (DMN) systems were successfully fabricated through in situ precipitation and conventional micromolding processes. The precipitated silica nanoparticles formed an interconnected network within the HA matrix, ranging in size from 25 to 230 nm. The optimal silica content for HA-Si composite MN systems should be up to 20 % by volume to maintain structural integrity and mechanical properties. HA-Si composite MNs with up to 20 % Si showed improved penetration efficiency and reduced degradation rates compared to pure HA MNs, thereby expanding the operational window. The HA-Si composite MNs retained good drug delivery capabilities and biocompatibility.

Slippery Viscosity-Sensing Platform with Time Readout for the Detection of Hyaluronidase and Its Inhibitor

Hyaluronidase (HAase) is a biomarker for cancer, and its detection is of great significance for early diagnosis. However, the requirement of sophisticated instruments, tedious operation procedures, and labeled molecules of conventional HAase biosensing methods hampers their widespread applications. Herein, we report a portable slippery viscosity-sensing platform with time readout for the first time and demonstrate HAase and tannic acid (TA, HAase inhibitor) detection as a model system. HAase specifically cleaves hyaluronic acid (HA) and decreases HA solution viscosity, thereby shortening the aqueous droplet's sliding time on a slippery surface. Thus, the HA solution viscosity alteration due to enzymatic hydrolysis is used to quantify the HAase concentration through the difference in the sliding time of the aqueous droplets on a slippery surface. The developed HAase sensing platform exhibits high sensitivity with a minimum detection limit of 0.23 U/mL and excellent specificity without the use of specialized instruments and labeled molecules. HAase detection in actual urine samples by a standard addition method is performed as well. Moreover, the quantitative detection of TA with an IC50 value of 37.68 ± 1.38 μg/mL is achieved. As an equipment-free, label-free, and high-portability sensing platform, this method holds promise in developing a user-friendly and inexpensive point-of-care testing (POCT) device for HAase detection, and its use can be extended to analyze other analytes with different stimuli-responsive polymers for great universality and expansibility in biosensing applications.

Immunomodulator-Mediated Suppressive Tumor Immune Microenvironment Remodeling Nanoplatform for Enhanced Immuno/Chemo/Photothermal Combination Therapy of Triple Negative Breast Cancer

Despite immunotherapy having revolutionized cancer therapy, the efficacy of immunotherapy in triple-negative breast cancer (TNBC) is seriously restricted due to the insufficient infiltration of mature dendritic cells (DCs) and the highly diffusion of immunosuppressive cells in the tumor microenvironment. Herein, an immunomodulatory nanoplatform (HA/Lipo@MTO@IMQ), in which the DCs could be maximally activated, was engineered to remarkably eradicate the tumor via the combination of suppressive tumor immune microenvironment reversal immunotherapy, chemotherapy, and photothermal therapy. It was noticed that the immunotherapy efficacy could be significantly facilitated by this triple-assistance therapy: First, a robust immunogenic cell death (ICD) effect was induced by mitoxantrone hydrochloride (MTO) to boost DCs maturation and cytotoxic T lymphocytes infiltration. Second, the powerful promaturation property of the toll-like receptor 7/8 (TLR7/8) agonist on DCs simultaneously strengthened the ICD effect and restricted antitumor immunity to the tumor bed and lymph nodes. On this basis, tumor-associated macrophages were also dramatically repolarized toward the antitumor M1 phenotype in response to TLR7/8 agonist to intensify the phagocytosis and reverse the immunosuppressive microenvironment. Furthermore, the recruitment of immunocompetent cells and tumor growth inhibition were further promoted by the photothermal characteristic. The nanoplatform with no conspicuous untoward effects exhibited a splendid ability to activate the systemic immune system so as to increase the immunogenicity of the tumor microenvironment, thus enhancing the tumor killing effect. Taken together, HA/Lipo@MTO@IMQ might highlight an efficient combination of therapeutic modality for TNBC.

Hyaluronic acid metabolism and chemotherapy resistance: recent advances and therapeutic potential

Hyaluronic acid (HA) is a major component of the extracellular matrix, providing essential mechanical scaffolding for cells and, at the same time, mediating essential biochemical signals required for tissue homeostasis. Many solid tumors are characterized by dysregulated HA metabolism, resulting in increased HA levels in cancer tissues. HA interacts with several cell surface receptors, such as cluster of differentiation 44 and receptor for hyaluronan-mediated motility, thus co-regulating important signaling pathways in cancer development and progression. In this review, we describe the enzymes controlling HA metabolism and its intracellular effectors emphasizing their impact on cancer chemotherapy resistance. We will also explore the current and future prospects of HA-based therapy, highlighting the opportunities and challenges in the field.

Hyaluronan-CD44 Interaction Regulates Mouse Retinal Progenitor Cells Migration, Proliferation and Neuronal Differentiation

Cell-based therapies have shown great potential because of their abilities to replace dying retinal neuron cells and preserve vision. The migration, proliferation and differentiation of retinal progenitor cells(RPCs) plays a vital role in the integration of the RPCs into the retina when transplanted into the host. Our study aimed to explore the effects of Hyaluronan(HA)-CD44 interactions on the regulation of RPCs migration, proliferation and differentiation, and investigate the underlying regulatory mechanisms. We found that CD44 was expressed in RPCs, and the HA-CD44 interaction markedly improved RPCs adhesion and migration. The stimulation of microRNA-21(miR-21) expression by the HA-CD44 interaction was protein kinase C (PKC)/Nanog-dependent in RPCs. Treatment of RPCs with PKC- or Nanog-specific ASODN or miR-21 antagomir effectively blocked HA-mediated RPCs adhesion and migration. Moreover, Rho-Kinase(ROK)/ Grb2-associated binders(Gab-1) associated phosphatidylinositol 3-kinase(PI3K)/AKT signalling activation was required for HA-CD44 interaction mediated RPCs proliferation and neuronal differentiation. Our findings demonstrated new roles for the HA-CD44 interaction in regulating the migration, proliferation and neuronal differentiation of RPCs. HA-CD44 signalling could represent a novel approach to controlling RPC fates, and the findings may be instructive for the application of RPCs for future therapeutic applications.

Boron in cancer therapeutics: An overview

Boron has become a crucial weapon in anticancer research due to its significant intervention in cell proliferation. Being an excellent bio-isosteric replacement of carbon, it has modulated the anticancer efficacy of various molecules in the development pipeline. It has elicited promising results through interactions with various therapeutic targets such as HIF-1α, steroid sulfatase, arginase, proteasome, etc. Since boron liberates alpha particles, it has a wide-scale application in Boron Neutron Capture therapy (BNCT), a radiotherapy that demonstrates selectivity towards cancer cells due to high boron uptake capacity. Significant advances in the medicinal chemistry of boronated compounds, such as boronated sugars, natural/unnatural amino acids, boronated DNA binders, etc., have been reported over the past few years as BNCT agents. In addition, boronated nanoparticles have assisted the field of bio-nano medicines by their usage in radiotherapy. This review exclusively focuses on the medicinal chemistry aspects, radiotherapeutic, and chemotherapeutic aspects of boron in cancer therapeutics. Emphasis is also given on the mechanism of action along with advantages over conventional therapies.

Mucin Glycans: A Target for Cancer Therapy

Mucin glycans are an important component of the mucus barrier and a vital defence against physical and chemical damage as well as pathogens. There are 20 mucins in the human body, which can be classified into secreted mucins and transmembrane mucins according to their distributions. The major difference between them is that secreted mucins do not have transmembrane structural domains, and the expression of each mucin is organ and cell-specific. Under physiological conditions, mucin glycans are involved in the composition of the mucus barrier and thus protect the body from infection and injury. However, abnormal expression of mucin glycans can lead to the occurrence of diseases, especially cancer, through various mechanisms. Therefore, targeting mucin glycans for the diagnosis and treatment of cancer has always been a promising research direction. Here, we first summarize the main types of glycosylation (O-GalNAc glycosylation and N-glycosylation) on mucins and the mechanisms by which abnormal mucin glycans occur. Next, how abnormal mucin glycans contribute to cancer development is described. Finally, we summarize MUC1-based antibodies, vaccines, radio-pharmaceuticals, and CAR-T therapies using the best characterized MUC1 as an example. In this section, we specifically elaborate on the recent new cancer therapy CAR-M, which may bring new hope to cancer patients.

A green-based approach for noninvasive skin rejuvenation: Potential application of hyaluronic acid

Gradually, loss of skin elasticity and elastic properties occurs after 30 years of age and will be associated with several changes, including creating wrinkles, skin laxity (sagging skin), and skin blemishes. In general, people all over the world are looking for ways to keep their facial skin young over time. There are several strategies to skin rejuvenate, including invasive and non-invasive methods. However, invasive methods have less popularity than non-invasive methods due to their need for specialist physicians (medical expertise), localized neuropathic pains for patients, the prevalence and incidence of skin infections, and high-cost clinical services. In the meantime, skin hydration is one of the simplest non-invasive methods for skin rejuvenation, and HA, with anti-aging and skin collagen-stimulating properties, has been introduced as a natural skin moisturizing agent. Therefore, since this composition maintains facial skin moisture and radiance, and improves its elasticity, it has always been considered by experts and specialist physicians. On the other hand, due to its lipophilic properties, hydrophilic macromolecules containing HA cannot pass through the stratum corneum. However, they have temporary and superficial softening effects on the skin. Hence, some nanocarriers have been suggested to overcome this problem and develop the properties and positive influences of HA on skin rejuvenation. Therefore, the present study aimed to introduce some new non-invasive approaches in facial skin rejuvenation, including applying liposomes, niosomes, ethosomes, and ionic liquids, to transport HA into the inner and deeper layers of the skin, including Dermis. In this review article, we examine non-invasive methods using nanoparticles to deliver HA to the epidermis and dermis of the skin for skin rejuvenation.

Emerging Advances in Microfluidic Hydrogel Droplets for Tissue Engineering and STEM Cell Mechanobiology

Hydrogel droplets are biodegradable and biocompatible materials with promising applications in tissue engineering, cell encapsulation, and clinical treatments. They represent a well-controlled microstructure to bridge the spatial divide between two-dimensional cell cultures and three-dimensional tissues, toward the recreation of entire organs. The applications of hydrogel droplets in regenerative medicine require a thorough understanding of microfluidic techniques, the biocompatibility of hydrogel materials, and droplet production and manipulation mechanisms. Although hydrogel droplets were well studied, several emerging advances promise to extend current applications to tissue engineering and beyond. Hydrogel droplets can be designed with high surface-to-volume ratios and a variety of matrix microstructures. Microfluidics provides precise control of the flow patterns required for droplet generation, leading to tight distributions of particle size, shape, matrix, and mechanical properties in the resultant microparticles. This review focuses on recent advances in microfluidic hydrogel droplet generation. First, the theoretical principles of microfluidics, materials used in fabrication, and new 3D fabrication techniques were discussed. Then, the hydrogels used in droplet generation and their cell and tissue engineering applications were reviewed. Finally, droplet generation mechanisms were addressed, such as droplet production, droplet manipulation, and surfactants used to prevent coalescence. Lastly, we propose that microfluidic hydrogel droplets can enable novel shear-related tissue engineering and regeneration studies.

Transgenic viral expression of PH-20, IL-12, and sPD1-Fc enhances immune cell infiltration and anti-tumor efficacy of an oncolytic virus

Oncolytic viruses are of significant clinical interest due to their ability to directly infect and kill tumors and enhance the anti-tumor immune response. Previously, we developed KLS-3010, a novel oncolytic virus derived from the International Health Department-White (IHD-W) strain vaccinia virus, which has robust tumoricidal effects. In the present study, we generated a recombinant oncolytic virus, KLS-3020, by inserting three transgenes (hyaluronidase [PH-20], interleukin-12 [IL-12], and soluble programmed cell death 1 fused to the Fc domain [sPD1-Fc]) into KLS-3010 and investigated its anti-tumor efficacy and ability to induce anti-tumor immune responses in CT26.WT and B16F10 mouse tumor models. A single injection of KLS-3020 significantly decreased tumor growth. The roles of the transgenes were investigated using viruses expressing each single transgene alone and KLS-3020. PH-20 promoted virus spread and tumor immune cell infiltration, IL-12 activated and reprogrammed T cells to inflammatory phenotypes, and sPD1-Fc increased intra-tumoral populations of activated T cells. The tumor-specific systemic immune response and the abscopal tumor control elicited by KLS-3020 were demonstrated in the CT26.WT tumor model. The insertion of transgenes into KLS-3020 increased its anti-tumor efficacy, supporting further clinical investigation of KLS-3020 as a novel oncolytic immunotherapy.

Synergy of GHK-Cu and hyaluronic acid on collagen IV upregulation via fibroblast and ex-vivo skin tests

INTRODUCTION

GHK-Cu and HA are two commonly used skin care ingredients, both of which were reported to enhance collagen synthesis. This work aims to investigate their co-effect on collagen regulation.

MATERIALS AND METHODS

In cell experiments, human dermal fibroblasts were treated by a series of GHK-Cu and HA combinations, and the expressions of collagen I, IV, and VII were measured by qRT-PCR. The best formula screened out from cell experiments were further studied by ex-vivo skin model, and the content of collagen IV was quantified by immunofluorescence method.

RESULTS

The combination GHK-Cu and HA was found to promote the generation of collagen I, IV, and VII. Especially, they form a synergy on collagen IV. At the ratio of 1:9, GHK-Cu and LMW HA deliver the strongest effect to elevate collagen IV synthesis by 25.4 times in cell test and 2.03 times in ex-vivo skin test.

CONCLUSION

The co-effect of GHK-Cu and HA was revealed. Their synergy brings an insight to anti-aging technology: choosing proper molecular weight of HA and managing its ratio with GHK-Cu could enhance DEJ health via stimulating collagen IV synthesis.

HYBID in osteoarthritis: Potential target for disease progression

HYBID is a new hyaluronan-degrading enzyme and exists in various cells of the human body. Recently, HYBID was found to over-express in the osteoarthritic chondrocytes and fibroblast-like synoviocytes. According to these researches, high level of HYBID is significantly correlated with cartilage degeneration in joints and hyaluronic acid degradation in synovial fluid. In addition, HYBID can affect inflammatory cytokine secretion, cartilage and synovium fibrosis, synovial hyperplasia via multiple signaling pathways, thereby exacerbating osteoarthritis. Based on the existing research of HYBID in osteoarthritis, HYBID can break the metabolic balance of HA in joints through the degradation ability independent of HYALs/CD44 system and furthermore affect cartilage structure and mechanotransduction of chondrocytes. In particular, in addition to HYBID itself being able to trigger some signaling pathways, we believe that low-molecular-weight hyaluronan produced by excess degradation can also stimulate some disease-promoting signaling pathways by replacing high-molecular-weight hyaluronan in joints. The specific role of HYBID in osteoarthritis is gradually revealed, and the discovery of HYBID raises the new way to treat osteoarthritis. In this review, the expression and basic functions of HYBID in joints were summarized, and reveal potential role of HYBID as a key target in treatment for osteoarthritis.

Making Hidden Cell Particle Interactions Visible by Thermal Noise Frequency Decomposition

Thermal noise drives cellular structures, bacteria, and viruses on different temporal and spatial scales. Their weak interactions with their environment can change on subsecond scales. However, particle interactions can be hidden or invisible-even when measured with thermal noise sensitivity, leading to misconceptions about their binding behavior. Here, it is demonstrated how invisible particle interactions at the cell periphery become visible by MHz interferometric thermal noise tracking and frequency decomposition at a spectral update rate of only 0.5 s. The particle fluctuations are analyzed in radial and lateral directions by a viscoelastic modulus G(ω,tex ) over the experiment time tex , revealing a surprisingly similar, frequency dependent response for different cell types. This response behavior can be explained by a mathematical model for molecular scale elasticity and damping. The method to reveal hidden interactions is tested at two examples: the stiffening of macrophage filopodia tips within 2 s with particle contact invisible by the fluctuation width. Second, the extent and stiffness of the soft cell glycocalyx is measured, which can be sensed by a particle only on microsecond-timescales, but which remains invisible on time-average. This concept study shows how to uncover hidden cellular interactions, if particle motions are measured at high-speed.

TMEM2 is a bona fide hyaluronidase possessing intrinsic catalytic activity

Transmembrane protein 2 (TMEM2) was originally identified as a membrane-anchored protein of unknown function. We previously demonstrated that TMEM2 can degrade hyaluronan (HA). Furthermore, we showed that induced global knockout of Tmem2 in adult mice results in rapid accumulation of incompletely degraded HA in bodily fluids and organs, supporting the identity of TMEM2 as a cell surface hyaluronidase. In spite of these advances, no direct evidence has been presented to demonstrate the intrinsic hyaluronidase activity of TMEM2. Here, we directly establish the catalytic activity of TMEM2. The ectodomain of TMEM2 (TMEM2ECD) was expressed as a His-tagged soluble protein and purified by affinity and size-exclusion chromatography. Both human and mouse TMEM2ECD robustly degrade fluorescein-labeled HA into 5 to 10 kDa fragments. TMEM2ECD exhibits this HA-degrading activity irrespective of the species of TMEM2 origin and the position of epitope tag insertion. The HA-degrading activity of TMEM2ECD is more potent than that of HYAL2, a hyaluronidase which, like TMEM2, has been implicated in cell surface HA degradation. Finally, we show that TMEM2ECD can degrade not only fluorescein-labeled HA but also native high-molecular weight HA. In addition to these core findings, our study reveals hitherto unrecognized confounding factors, such as the quality of reagents and the choice of assay systems, that could lead to erroneous conclusions regarding the catalytic activity of TMEM2. In conclusion, our results demonstrate that TMEM2 is a legitimate functional hyaluronidase. Our findings also raise cautions regarding the choice of reagents and methods for performing degradation assays for hyaluronidases.