bims-ecemfi 2024-06-16 papers

bims-ecemfi

Biomed News

on ECM and fibroblasts

Issue of 2024–06–16
sixteen papers selected by
Badri Narayanan Narasimhan, University of California, San Diego

The epithelial adherens junction component PLEKHA7 regulates ECM remodeling and cell behavior through miRNA-mediated regulation of MMP1 and LOX.
Beyond stiffness: deciphering the role of viscoelasticity in cancer evolution and treatment response.
Multicompartmentalized microvascularized tumor-on-a-chip to study tumor-stroma interactions and drug resistance in ovarian cancer.
Mechanoimmunology in the solid tumor microenvironment.
Controlling Pericellular Oxygen Tension in Cell Culture Reveals Distinct Breast Cancer Responses to Low Oxygen Tensions.
Synthetic biodegradable microporous hydrogels for in vitro 3D culture of functional human bone cell networks.
Proteolysis-free amoeboid migration of melanoma cells through crowded environments via bleb-driven worrying.
Mechanobiological Modulation of In Vitro Astrocyte Reactivity Using Variable Gel Stiffness.
Collagen density regulates tip-stalk cell rearrangement during angiogenesis via cellular bioenergetics.
Integrin Mechanosensing relies on Pivot-clip Mechanism to Reinforce Cell Adhesion.
Molecular and epigenetic ex vivo profiling of testis cancer-associated fibroblasts and their interaction with germ cell tumor cells and macrophages.
Cancer cell sedimentation in 3D cultures reveals active migration regulated by self-generated gradients and adhesion sites.
Macrophage subtypes inhibit breast cancer proliferation in culture.
A multicrosslinked network composite hydrogel scaffold based on DLP photocuring printing for nasal cartilage repair.
Morphology, repulsion, and ordering of red blood cells in viscoelastic flows under confinement.
Hematoxylin and Eosin Architecture Uncovers Clinically Divergent Niches in Pancreatic Cancer.

bioRxiv. 2024 May 30. pii: 2024.05.28.596237. [Epub ahead of print]

The epithelial adherens junction component PLEKHA7 regulates ECM remodeling and cell behavior through miRNA-mediated regulation of MMP1 and LOX.

Amanda C Daulagala, Metin Cetin, Joyce Nair-Menon, Douglas W Jimenez, Mary Catherine Bridges, Amy D Bradshaw, Ozgur Sahin, Antonis Kourtidis.

Epithelial adherens junctions (AJs) are cell-cell adhesion complexes that are influenced by tissue mechanics, such as those emanating from the extracellular matrix (ECM). Here, we introduce a mechanism whereby epithelial AJs can also regulate the ECM. We show that the AJ component PLEKHA7 regulates levels and activity of the key ECM remodeling components MMP1 and LOX in well-differentiated colon epithelial cells, through the miR-24 and miR-30c miRNAs. PLEKHA7 depletion in epithelial cells results in LOX-dependent ECM remodeling in culture and in the colonic mucosal lamina propria in mice. Furthermore, PLEKHA7-depleted cells exhibit increased migration and invasion rates that are MMP1- and LOX-dependent, and form colonies in 3D cultures that are larger in size and acquire aberrant morphologies in stiffer matrices. These results reveal an AJ-mediated mechanism, through which epithelial cells drive ECM remodeling to modulate their behavior, including acquisition of phenotypes that are hallmarks of conditions such as fibrosis and tumorigenesis.
Teaser: Epithelial cells instruct ECM remodeling to modulate their behavior, as a result of adherens junction and miRNA disruption.

DOI: https://doi.org/10.1101/2024.05.28.596237
Biofabrication. 2024 Jun 11.

Beyond stiffness: deciphering the role of viscoelasticity in cancer evolution and treatment response.

Ana Zubiarrain-Laserna, Daniel Martínez-Moreno, Julia Lopez de Andres, Laura de Lara-Peña, Olatz Guaresti, Ane Miren Zaldua, Gema Jiménez, Juan Antonio Marchal.

  There is increasing evidence that cancer progression is linked to tissue viscoelasticity, which challenges the commonly accepted notion that stiffness is the main mechanical hallmark of cancer. However, this new insight has not reached widespread clinical use, as most clinical trials focus on the application of tissue elasticity and stiffness in diagnostic, therapeutic, and surgical planning. Therefore, there is a need to advance the fundamental understanding of the effect of viscoelasticity on cancer progression, to develop novel mechanical biomarkers of clinical significance. Tissue viscoelasticity is largely determined by the extracellular matrix (ECM), which can be simulated in vitro using hydrogel-based platforms. Since the mechanical properties of hydrogels can be easily adjusted by changing parameters such as molecular weight and crosslinking type, they provide a platform to systematically study the relationship between ECM viscoelasticity and cancer progression. This review begins with an overview of cancer viscoelasticity, describing how tumor cells interact with biophysical signals in their environment, how they contribute to tumor viscoelasticity, and how this translates into cancer progression. Next, an overview of clinical trials focused on measuring biomechanical properties of tumors is presented, highlighting the biomechanical properties utilized for cancer diagnosis and monitoring. Finally, this review examines the use of biofabricated tumor models for studying the impact of ECM viscoelasticity on cancer behavior and progression and it explores potential avenues for future research on the production of more sophisticated and biomimetic tumor models, as well as their mechanical evaluation.

Keywords:  cancer; elastography; hydrogels; mechanotransduction; tumor microenvironment; tumor models; viscoelasticity

DOI:  https://doi.org/10.1088/1758-5090/ad5705
bioRxiv. 2024 Jun 02. pii: 2024.05.29.596456. [Epub ahead of print]

Multicompartmentalized microvascularized tumor-on-a-chip to study tumor-stroma interactions and drug resistance in ovarian cancer.

Simona Plesselova, Kristin Calar, Hailey Axemaker, Emma Sahly, Pilar de la Puente.

Introduction: The majority of ovarian cancer (OC) patients receiving standard of care chemotherapy develop chemoresistance within 5 years. The tumor microenvironment (TME) is a dynamic and influential player in disease progression and therapeutic response. However, there is a lack of models that allow us to elucidate the compartmentalized nature of TME in a controllable, yet physiologically relevant manner and its critical role in modulating drug resistance.
Methods: We developed a 3D microvascularized multiniche tumor-on-a-chip formed by five chambers (central cancer chamber, flanked by two lateral stromal chambers and two external circulation chambers) to recapitulate OC-TME compartmentalization and study its influence on drug resistance. Stromal chambers included endothelial cells alone or cocultured with normal fibroblasts or cancer-associated fibroblasts (CAF).
Results: The tumor-on-a-chip recapitulated spatial TME compartmentalization including vessel-like structure, stromal-mediated extracellular matrix (ECM) remodeling, generation of oxygen gradients, and delayed drug diffusion/penetration from the circulation chamber towards the cancer chamber. The cancer chamber mimicked metastasis-like migration and increased drug resistance to carboplatin/paclitaxel treatment in the presence of CAF when compared to normal fibroblasts. CAF-mediated drug resistance was rescued by ECM targeted therapy. Critically, these results demonstrate that cellular crosstalk recreation and spatial organization through compartmentalization are essential to determining the effect of the compartmentalized OC-TME on drug resistance.
Conclusions: Our results present a functionally characterized microvascularized multiniche tumor-on-a-chip able to recapitulate TME compartmentalization influencing drug resistance. This technology holds the potential to guide the design of more effective and targeted therapeutic strategies to overcome chemoresistance in OC.

DOI: https://doi.org/10.1101/2024.05.29.596456
Biochem Soc Trans. 2024 Jun 10. pii: BST20231427. [Epub ahead of print]

Mechanoimmunology in the solid tumor microenvironment.

Matteo Golo, Peter L H Newman, Daryan Kempe, Maté Biro.

  The tumor microenvironment (TME) is a complex and dynamic ecosystem that adjoins the cancer cells within solid tumors and comprises distinct components such as extracellular matrix, stromal and immune cells, blood vessels, and an abundance of signaling molecules. In recent years, the mechanical properties of the TME have emerged as critical determinants of tumor progression and therapeutic response. Aberrant mechanical cues, including altered tissue architecture and stiffness, contribute to tumor progression, metastasis, and resistance to treatment. Moreover, burgeoning immunotherapies hold great promise for harnessing the immune system to target and eliminate solid malignancies; however, their success is hindered by the hostile mechanical landscape of the TME, which can impede immune cell infiltration, function, and persistence. Consequently, understanding TME mechanoimmunology - the interplay between mechanical forces and immune cell behavior - is essential for developing effective solid cancer therapies. Here, we review the role of TME mechanics in tumor immunology, focusing on recent therapeutic interventions aimed at modulating the mechanical properties of the TME to potentiate T cell immunotherapies, and innovative assays tailored to evaluate their clinical efficacy.

Keywords:  T-cells; biophysics; cancer; extracellular matrix; immune response; tumor microenvironments

DOI:  https://doi.org/10.1042/BST20231427
Adv Sci (Weinh). 2024 Jun 14. e2402557

Controlling Pericellular Oxygen Tension in Cell Culture Reveals Distinct Breast Cancer Responses to Low Oxygen Tensions.

Zachary J Rogers, Thibault Colombani, Saad Khan, Khushbu Bhatt, Alexandra Nukovic, Guanyu Zhou, Benjamin M Woolston, Cormac T Taylor, Daniele M Gilkes, Nikolai Slavov, Sidi A Bencherif.

  In oxygen (O2)-controlled cell culture, an indispensable tool in biological research, it is presumed that the incubator setpoint equals the O2 tension experienced by cells (i.e., pericellular O2). However, it is discovered that physioxic (5% O2) and hypoxic (1% O2) setpoints regularly induce anoxic (0% O2) pericellular tensions in both adherent and suspension cell cultures. Electron transport chain inhibition ablates this effect, indicating that cellular O2 consumption is the driving factor. RNA-seq analysis revealed that primary human hepatocytes cultured in physioxia experience ischemia-reperfusion injury due to cellular O2 consumption. A reaction-diffusion model is developed to predict pericellular O2 tension a priori, demonstrating that the effect of cellular O2 consumption has the greatest impact in smaller volume culture vessels. By controlling pericellular O2 tension in cell culture, it is found that hypoxia vs. anoxia induce distinct breast cancer transcriptomic and translational responses, including modulation of the hypoxia-inducible factor (HIF) pathway and metabolic reprogramming. Collectively, these findings indicate that breast cancer cells respond non-monotonically to low O2, suggesting that anoxic cell culture is not suitable for modeling hypoxia. Furthermore, it is shown that controlling atmospheric O2 tension in cell culture incubators is insufficient to regulate O2 in cell culture, thus introducing the concept of pericellular O2-controlled cell culture.

Keywords:  anoxia; breast cancer; cancer metabolism; cell culture; hypoxia; hypoxia‐inducible factors; oxygen; physioxia

DOI:  https://doi.org/10.1002/advs.202402557
Nat Commun. 2024 Jun 13. 15(1): 5027

Synthetic biodegradable microporous hydrogels for in vitro 3D culture of functional human bone cell networks.

Doris Zauchner, Monica Zippora Müller, Marion Horrer, Leana Bissig, Feihu Zhao, Philipp Fisch, Sung Sik Lee, Marcy Zenobi-Wong, Ralph Müller, Xiao-Hua Qin.

Generating 3D bone cell networks in vitro that mimic the dynamic process during early bone formation remains challenging. Here, we report a synthetic biodegradable microporous hydrogel for efficient formation of 3D networks from human primary cells, analysis of cell-secreted extracellular matrix (ECM) and microfluidic integration. Using polymerization-induced phase separation, we demonstrate dynamic in situ formation of microporosity (5-20 µm) within matrix metalloproteinase-degradable polyethylene glycol hydrogels in the presence of living cells. Pore formation is triggered by thiol-Michael-addition crosslinking of a viscous precursor solution supplemented with hyaluronic acid and dextran. The resulting microporous architecture can be fine-tuned by adjusting the concentration and molecular weight of dextran. After encapsulation in microporous hydrogels, human mesenchymal stromal cells and osteoblasts spread rapidly and form 3D networks within 24 hours. We demonstrate that matrix degradability controls cell-matrix remodeling, osteogenic differentiation, and deposition of ECM proteins such as collagen. Finally, we report microfluidic integration and proof-of-concept osteogenic differentiation of 3D cell networks under perfusion on chip. Altogether, this work introduces a synthetic microporous hydrogel to efficiently differentiate 3D human bone cell networks, facilitating future in vitro studies on early bone development.

DOI: https://doi.org/10.1038/s41467-024-49280-3
Dev Cell. 2024 Jun 05. pii: S1534-5807(24)00342-3. [Epub ahead of print]

Proteolysis-free amoeboid migration of melanoma cells through crowded environments via bleb-driven worrying.

Meghan K Driscoll, Erik S Welf, Andrew Weems, Etai Sapoznik, Felix Zhou, Vasanth S Murali, Juan Manuel García-Arcos, Minna Roh-Johnson, Matthieu Piel, Kevin M Dean, Reto Fiolka, Gaudenz Danuser.

  In crowded microenvironments, migrating cells must find or make a path. Amoeboid cells are thought to find a path by deforming their bodies to squeeze through tight spaces. Yet, some amoeboid cells seem to maintain a near-spherical morphology as they move. To examine how they do so, we visualized amoeboid human melanoma cells in dense environments and found that they carve tunnels via bleb-driven degradation of extracellular matrix components without the need for proteolytic degradation. Interactions between adhesions and collagen at the cell front induce a signaling cascade that promotes bleb enlargement via branched actin polymerization. Large blebs abrade collagen, creating feedback between extracellular matrix structure, cell morphology, and polarization that enables both path generation and persistent movement.

Keywords:  amoeboid; blebbing; cell migration; computer vision; extracellular matrix remodeling; fluorescence microscopy; light-sheet microscopy; macropinocytosis; melanoma

DOI:  https://doi.org/10.1016/j.devcel.2024.05.024
ACS Biomater Sci Eng. 2024 Jun 13.

Mechanobiological Modulation of In Vitro Astrocyte Reactivity Using Variable Gel Stiffness.

Julia C Benincasa, Marianne I Madias, Rebecca M Kandell, Lina M Delgado-Garcia, Adam J Engler, Ester J Kwon, Marimelia A Porcionatto.

  After traumatic brain injury, the brain extracellular matrix undergoes structural rearrangement due to changes in matrix composition, activation of proteases, and deposition of chondroitin sulfate proteoglycans by reactive astrocytes to produce the glial scar. These changes lead to a softening of the tissue, where the stiffness of the contusion "core" and peripheral "pericontusional" regions becomes softer than that of healthy tissue. Pioneering mechanotransduction studies have shown that soft substrates upregulate intermediate filament proteins in reactive astrocytes; however, many other aspects of astrocyte biology remain unclear. Here, we developed a platform for the culture of cortical astrocytes using polyacrylamide (PA) gels of varying stiffness (measured in Pascal; Pa) to mimic injury-related regions in order to investigate the effects of tissue stiffness on astrocyte reactivity and morphology. Our results show that substrate stiffness influences astrocyte phenotype; soft 300 Pa substrates led to increased GFAP immunoreactivity, proliferation, and complexity of processes. Intermediate 800 Pa substrates increased Aggrecan+, Brevican+, and Neurocan+ astrocytes. The stiffest 1 kPa substrates led to astrocytes with basal morphologies, similar to a physiological state. These results advance our understanding of astrocyte mechanotransduction processes and provide evidence of how substrates with engineered stiffness can mimic the injury microenvironment.

Keywords:  astrocyte morphology; astrogliosis; glial scar; matrix stiffness; polyacrylamide gels

DOI:  https://doi.org/10.1021/acsbiomaterials.4c00229
APL Bioeng. 2024 Jun;8(2): 026120

Collagen density regulates tip-stalk cell rearrangement during angiogenesis via cellular bioenergetics.

Wenjun Wang, Matthew R Zanotelli, Lindsey N Sabo, Emily D Fabiano, Natalie M Goldfield, Chloe Le, Elle P Techasiriwan, Santiago Lopez, Emily D Berestesky, Cynthia A Reinhart-King.

Tumor vasculature plays a crucial role in tumor progression, affecting nutrition and oxygen transportation as well as the efficiency of drug delivery. While targeting pro-angiogenic growth factors has been a significant focus for treating tumor angiogenesis, recent studies indicate that metabolism also plays a role in regulating endothelial cell behavior. Like cancer cells, tumor endothelial cells undergo metabolic changes that regulate rearrangement for tip cell position during angiogenesis. Our previous studies have shown that altered mechanical properties of the collagen matrix regulate angiogenesis and can promote a tumor vasculature phenotype. Here, we examine the effect of collagen density on endothelial cell tip-stalk cell rearrangement and cellular energetics during angiogenic sprouting. We find that increased collagen density leads to an elevated energy state and an increased rate of tip-stalk cell switching, which is correlated with the energy state of the cells. Tip cells exhibit higher glucose uptake than stalk cells, and inhibition of glucose uptake revealed that invading sprouts rely on glucose to meet elevated energy requirements for invasion in dense matrices. This work helps to elucidate the complex interplay between the mechanical microenvironment and the endothelial cell metabolic status during angiogenesis, which could have important implications for developing new anti-cancer therapies.

DOI: https://doi.org/10.1063/5.0195249
Biophys J. 2024 Jun 13. pii: S0006-3495(24)00391-6. [Epub ahead of print]

Integrin Mechanosensing relies on Pivot-clip Mechanism to Reinforce Cell Adhesion.

Andre R Montes, Anahi Barroso, Wei Wang, Grace D O'Connell, Adrian B Tepole, Mohammad R K Mofrad.

Cells intricately sense mechanical forces from their surroundings, driving biophysical and biochemical activities. This mechanosensing phenomenon occurs at the cell-matrix interface, where mechanical forces resulting from cellular motion, such as migration or matrix stretching, are exchanged through surface receptors, primarily integrins, and their corresponding matrix ligands. A pivotal player in this interaction is the α5β1 integrin and fibronectin (FN) bond, known for its role in establishing cell adhesion sites for migration. However, upregulation of the α5β1-FN bond is associated with uncontrolled cell metastasis. This bond operates through catch bond dynamics, wherein the bond lifetime paradoxically increases with greater force. The mechanism sustaining the characteristic catch bond dynamics of α5β1-FN remains unclear. Leveraging molecular dynamics simulations, our approach unveils a pivot-clip mechanism. Two key binding sites on FN, namely the synergy site and the RGD (arg-gly-asp) motif, act as active points for structural changes in α5β1 integrin. Conformational adaptations at these sites are induced by a series of hydrogen bond formations and breaks at the synergy site. We disrupt these adaptations through a double mutation on FN, known to reduce cell adhesion. A whole-cell finite element model is employed to elucidate how the synergy site may promote dynamic α5β1-FN binding, resisting cell contraction. In summary, our study integrates molecular and cellular-level modeling to propose that FN's synergy site reinforces cell adhesion through enhanced binding dynamics and a mechanosensitive pivot-clip mechanism. This work sheds light on the interplay between mechanical forces and cell-matrix interactions, contributing to our understanding of cellular behaviors in physiological and pathological contexts.

DOI: https://doi.org/10.1016/j.bpj.2024.06.008
Matrix Biol. 2024 Jun 06. pii: S0945-053X(24)00077-5. [Epub ahead of print]

Molecular and epigenetic ex vivo profiling of testis cancer-associated fibroblasts and their interaction with germ cell tumor cells and macrophages.

Alexa Stephan, Jan-Henrik Suhrmann, Margaretha A Skowron, Yue Che, Gereon Poschmann, Patrick Petzsch, Catena Kresbach, Wasco Wruck, Pailin Pongratanakul, James Adjaye, Kai Stühler, Karl Köhrer, Ulrich Schüller, Daniel Nettersheim.

  Germ cell tumors (GCT) are the most common solid tumors in young men of age 15 - 40. In previous studies, we profiled the interaction of GCT cells with cells of the tumor microenvironment (TM). Earlier studies showed that especially the 3D interaction of fibroblasts (FB) or macrophages with GCT cells influenced the growth behavior and cisplatin response as well as the transcriptome and secretome of the tumor cells, suggesting that the crosstalk of these cells with GCT cells is crucial for tumor progression and therapy outcome. In this study, we shed light on the mechanisms of activation of cancer-associated fibroblasts (CAF) in the GCT setting and their effects on GCT cells lines and the monocyte cell line THP-1. Ex vivo cultures of GCT-derived CAF were established and characterized molecularly and epigenetically by performing DNA methylation arrays, RNA sequencing, and mass spectrometry-based secretome analysis. We demonstrated that the activation state of CAF is influenced by their former prevailing tumor environment in which they have resided. Hereby, we postulated that seminoma (SE) and embryonal carcinoma (EC) activate CAF, while teratoma (TER) play only a minor role in CAF formation. In turn, CAF influence proliferation and the expression of cisplatin sensitivity-related factors in GCT cells lines as well as polarization of in vitro-induced macrophages by the identified effector molecules IGFBP1, LGALS3BP, LYVE1, and PTX3. Our data suggests that the vital interaction of CAF with GCT cells and with macrophages has a huge influence for shaping the extracellular matrix as well as for recruitment of immune cells to the tumor microenvironment. In conclusion, therapeutically interfering with CAF and / or macrophages in addition to the standard therapy might slow-down progression of GCT and re-shaping of the TM to a tumor-promoting environment. Significance: The interaction of CAF with GCT and macrophages considerably influences the microenvironment. Thus, therapeutically interfering with CAF might slow-down progression of GCT and re-shaping of the microenvironment to a tumor-promoting environment.

Keywords:  DNA methylation; Extracellular Matrix; Fibroblasts; Germ cell tumors; Microenvironment; Secretome; cancer-associated fibroblasts

DOI:  https://doi.org/10.1016/j.matbio.2024.06.001
PLoS Comput Biol. 2024 Jun 11. 20(6): e1012112

Cancer cell sedimentation in 3D cultures reveals active migration regulated by self-generated gradients and adhesion sites.

Nikolaos M Dimitriou, Salvador Flores-Torres, Maria Kyriakidou, Joseph Matthew Kinsella, Georgios D Mitsis.

Cell sedimentation in 3D hydrogel cultures refers to the vertical migration of cells towards the bottom of the space. Understanding this poorly examined phenomenon may allow us to design better protocols to prevent it, as well as provide insights into the mechanobiology of cancer development. We conducted a multiscale experimental and mathematical examination of 3D cancer growth in triple negative breast cancer cells. Migration was examined in the presence and absence of Paclitaxel, in high and low adhesion environments and in the presence of fibroblasts. The observed behaviour was modeled by hypothesizing active migration due to self-generated chemotactic gradients. Our results confirmed this hypothesis, whereby migration was likely to be regulated by the MAPK and TGF-βpathways. The mathematical model enabled us to describe the experimental data in absence (normalized error<40%) and presence of Paclitaxel (normalized error<10%), suggesting inhibition of random motion and advection in the latter case. Inhibition of sedimentation in low adhesion and co-culture experiments further supported the conclusion that cells actively migrated downwards due to the presence of signals produced by cells already attached to the adhesive glass surface.

DOI: https://doi.org/10.1371/journal.pcbi.1012112
bioRxiv. 2024 Jun 01. pii: 2024.06.01.596963. [Epub ahead of print]

Macrophage subtypes inhibit breast cancer proliferation in culture.

Sophia R S Varady, Daniel Greiner, Minna Roh-Johnson.

Macrophages are a highly plastic cell type that adopt distinct subtypes and functional states depending on environmental cues. These functional states can vary wildly, with distinct macrophages capable of displaying opposing functions. We sought to understand how macrophage subtypes that exist on two ends of a spectrum influence the function of other cells. We used a co-culture system with primary human macrophages to probe the effects of macrophage subtypes on breast cancer cell proliferation. Our studies revealed a surprising phenotype in which both macrophage subtypes inhibited cancer cell proliferation compared to cancer cells alone. Of particular interest, using two different proliferation assays with two different breast cancer cell lines, we showed that differentiating macrophages into a "pro-tumor" subtype inhibited breast cancer cell proliferation. These findings are inconsistent with the prevailing interpretation that "pro-tumor" macrophages promote cancer cell proliferation and suggest a re-evaluation of how these interpretations are made.

DOI: https://doi.org/10.1101/2024.06.01.596963
Biotechnol Bioeng. 2024 Jun 14.

A multicrosslinked network composite hydrogel scaffold based on DLP photocuring printing for nasal cartilage repair.

Wendan Jia, Zixian Liu, Lei Sun, Yanyan Cao, Zhizhong Shen, Meng Li, Yang An, Hulin Zhang, Shengbo Sang.

  Natural hydrogels are widely employed in tissue engineering and have excellent biodegradability and biocompatibility. Unfortunately, the utilization of such hydrogels in the field of three-dimensional (3D) printing nasal cartilage is constrained by their subpar mechanical characteristics. In this study, we provide a multicrosslinked network hybrid ink made of photocurable gelatin, hyaluronic acid, and acrylamide (AM). The ink may be processed into intricate 3D hydrogel structures with good biocompatibility and high stiffness properties using 3D printing technology based on digital light processing (DLP), including intricate shapes resembling noses. By varying the AM content, the mechanical behavior and biocompatibility of the hydrogels can be adjusted. In comparison to the gelatin methacryloyl (GelMA)/hyaluronic acid methacryloyl (HAMA) hydrogel, adding AM considerably enhances the hydrogel's mechanical properties while also enhancing printing quality. Meanwhile, the biocompatibility of the multicrosslinked network hydrogels and the development of cartilage were assessed using neonatal Sprague-Dawley (SD) rat chondrocytes (CChons). Cells sown on the hydrogels considerably multiplied after 7 days of culture and kept up the expression of particular proteins. Together, our findings point to GelMA/HAMA/polyacrylamide (PAM) hydrogel as a potential material for nasal cartilage restoration. The photocuring multicrosslinked network ink composed of appropriate proportions of GelMA/HAMA/PAM is very suitable for DLP 3D printing and will play an important role in the construction of nasal cartilage, ear cartilage, articular cartilage, and other tissues and organs in the future. Notably, previous studies have not explored the application of 3D-printed GelMA/HAMA/PAM hydrogels for nasal cartilage regeneration.

Keywords:  GelMA; HAMA; biocompatible; biodegradable; nasal cartilage repair; natural‐synthetic polymer biohybrid hydrogel

DOI:  https://doi.org/10.1002/bit.28769
Soft Matter. 2024 Jun 14.

Morphology, repulsion, and ordering of red blood cells in viscoelastic flows under confinement.

Steffen M Recktenwald, Yazdan Rashidi, Ian Graham, Paulo E Arratia, Francesco Del Giudice, Christian Wagner.

Red blood cells (RBC), the primary carriers of oxygen in the body, play a crucial role across several biomedical applications, while also being an essential model system of a deformable object in the microfluidics and soft matter fields. However, RBC behavior in viscoelastic liquids, which holds promise in enhancing microfluidic diagnostic applications, remains poorly studied. We here show that using viscoelastic polymer solutions as a suspending carrier causes changes in the clustering and shape of flowing RBC in microfluidic flows when compared to a standard Newtonian suspending liquid. Additionally, when the local RBC concentration increases to a point where hydrodynamic interactions take place, we observe the formation of equally-spaced RBC structures, resembling the viscoelasticity-driven ordered particles observed previously in the literature, thus providing the first experimental evidence of viscoelasticity-driven cell ordering. The observed RBC ordering, unaffected by polymer molecular architecture, persists as long as the surrounding medium exhibits shear-thinning, viscoelastic properties. Complementary numerical simulations reveal that viscoelasticity-induced repulsion between RBCs leads to equidistant structures, with shear-thinning modulating this effect. Our results open the way for the development of new biomedical technologies based on the use of viscoelastic liquids while also clarifying fundamental aspects related to multibody hydrodynamic interactions in viscoelastic microfluidic flows.

DOI: https://doi.org/10.1039/d4sm00446a
Tissue Eng Part A. 2024 Jun 14.

Hematoxylin and Eosin Architecture Uncovers Clinically Divergent Niches in Pancreatic Cancer.

Jason L Guo, David M Lopez, Shamik Mascharak, Deshka S Foster, Anum Khan, Michael F Davitt, Alan T Nguyen, Austin R Burcham, Malini S Chinta, Nicholas J Guardino, Michelle Griffin, Elisabeth Miller, Michael Januszyk, Shyam S Raghavan, Teri A Longacre, Daniel J Delitto, Jeffrey A Norton, Michael T Longaker.

Pancreatic ductal adenocarcinoma (PDAC) represents one of the only cancers with an increasing incidence rate and is often associated with intra- and peri-tumoral scarring, referred to as desmoplasia. This scarring is highly heterogeneous in extracellular matrix (ECM) architecture and plays complex roles in both tumor biology and clinical outcomes that are not yet fully understood. Using hematoxylin and eosin (H&E), a routine histological stain utilized in existing clinical workflows, we quantified ECM architecture in 85 patient samples to assess relationships between desmoplastic architecture and clinical outcomes such as survival time and disease recurrence. By utilizing unsupervised machine learning (ML) to summarize a latent space across 147 local (e.g. fiber length, solidity) and global (e.g. fiber branching, porosity) H&E-based features, we identified a continuum of histological architectures that were associated with differences in both survival and recurrence. Further, we mapped H&E architectures to a CO-Detection by indEXing (CODEX) reference atlas, revealing localized cell- and protein-based niches associated with outcome-positive vs. outcome-negative scarring in the tumor microenvironment. Overall, our study utilizes standard H&E staining to uncover clinically relevant associations between desmoplastic organization and PDAC outcomes, offering a translatable pipeline to support prognostic decision-making and a blueprint of spatial-biological factors for modeling by tissue engineering methods.

DOI: https://doi.org/10.1089/ten.TEA.2024.0039