Macrophage heterogeneity in bone metastasis.

Previous studies illustrated that macrophage, a type of innate immune cell, plays critical roles in tumour progression and metastasis. Bone is the most frequent site of metastasis for several cancer types including breast, prostate, and lung. In bone metastasis, osteoclast, a macrophage subset specialized in bone resorption, was heavily investigated in the past. Recent studies illustrated that other macrophage subsets, e.g. monocyte-derived macrophages, and bone resident macrophages, promoted bone metastasis independent of osteoclast function. These novel mechanisms further improved our understanding of macrophage heterogeneity in the context of bone metastasis and illustrated new opportunities for future studies.

Engineered tissue geometry and Plakophilin-2 regulate electrophysiology of human iPSC-derived cardiomyocytes.

Engineered heart tissues have been created to study cardiac biology and disease in a setting that more closely mimics in vivo heart muscle than 2D monolayer culture. Previously published studies suggest that geometrically anisotropic micro-environments are crucial for inducing "in vivo like" physiology from immature cardiomyocytes. We hypothesized that the degree of cardiomyocyte alignment and prestress within engineered tissues is regulated by tissue geometry and, subsequently, drives electrophysiological development. Thus, we studied the effects of tissue geometry on electrophysiology of micro-heart muscle arrays (µHM) engineered from human induced pluripotent stem cells (iPSCs). Elongated tissue geometries elicited cardiomyocyte shape and electrophysiology changes led to adaptations that yielded increased calcium intake during each contraction cycle. Strikingly, pharmacologic studies revealed that a threshold of prestress and/or cellular alignment is required for sodium channel function, whereas L-type calcium and rapidly rectifying potassium channels were largely insensitive to these changes. Concurrently, tissue elongation upregulated sodium channel (NaV1.5) and gap junction (Connexin 43, Cx43) protein expression. Based on these observations, we leveraged elongated µHM to study the impact of loss-of-function mutation in Plakophilin 2 (PKP2), a desmosome protein implicated in arrhythmogenic disease. Within µHM, PKP2 knockout cardiomyocytes had cellular morphology similar to what was observed in isogenic controls. However, PKP2-/- tissues exhibited lower conduction velocity and no functional sodium current. PKP2 knockout µHM exhibited geometrically linked upregulation of sodium channel but not Cx43, suggesting that post-translational mechanisms, including a lack of ion channel-gap junction communication, may underlie the lower conduction velocity observed in tissues harboring this genetic defect. Altogether, these observations demonstrate that simple, scalable micro-tissue systems can provide the physiologic stresses necessary to induce electrical remodeling of iPS-CM to enable studies on the electrophysiologic consequences of disease-associated genomic variants.

Computationally guided AAV engineering for enhanced gene delivery.

Gene delivery vehicles based on adeno-associated viruses (AAVs) are enabling increasing success in human clinical trials, and they offer the promise of treating a broad spectrum of both genetic and non-genetic disorders. However, delivery efficiency and targeting must be improved to enable safe and effective therapies. In recent years, considerable effort has been invested in creating AAV variants with improved delivery, and computational approaches have been increasingly harnessed for AAV engineering. In this review, we discuss how computationally designed AAV libraries are enabling directed evolution. Specifically, we highlight approaches that harness sequences outputted by next-generation sequencing (NGS) coupled with machine learning (ML) to generate new functional AAV capsids and related regulatory elements, pushing the frontier of what vector engineering and gene therapy may achieve.

Cancer Pain Management with Traditional Chinese Medicine: Current Status and Future Perspectives.

Cancer pain, especially the moderate-to-severe pain experienced by patients with advanced cancer, is still one of the most challenging clinical problems. The current mainstream pharmacological treatment for cancer pain involves applying opioid medications and other pain-killing drugs. However, analgesic drugs have many adverse effects such as addiction, tolerance, and other formidable clinical and social issues. Thus, finding a new therapeutic approach to treat cancer pain is essential. Traditional Chinese medicine (TCM) has been increasingly applied in clinical practice because of its good efficacy and few side effects. However, its mechanisms of action in treating pain are still under investigation. The most important mechanism of cancer pain is that a large amount of pain-causing substances are secreted from cancer cells and promote their growth and invasion. The physical and chemical stimulations of these substances exist along with the cancer growth, leading to constantly increased pain sensation. Whether cancer pain can be alleviated by inhibiting cancer cells from releasing the substances and changing the microenvironment around the cancer mass, or even by eliminating pain-causing substances, is largely unknown. Based on TCM theory, this study reported that the aforementioned approach could effectively manage different cancer pains by tonifying qi, clearing and activating channels and meridians, and strengthening body resistance. The TCM therapies activate blood circulation, remove blood stasis, and nourish the heart. Commonly used Chinese herbal drugs include Corydalis yanhusuo, Angelica dahurica, and Ligusticum chuanxiong. Instead of using conventional analgesics to reduce pain, we should focus on using TCM modalities to alleviate cancer pain and increase the quality of life in patients suffering from cancer pain. TCM should provide us with a new strategy for managing cancer pain.

Protocol for near-infrared optogenetics manipulation of neurons and motor behavior in C. elegans using emissive upconversion nanoparticles.

In deep tissue, optogenetics faces limitations with visible light. Here, we present a protocol for near-infrared (NIR) optogenetics manipulation of neurons and motor behavior in Caenorhabditis elegans using emissive upconversion nanoparticles (UCNPs). We describe steps for synthesizing and modifying UCNPs. We then detail procedures for regulating neurons using these UCNPs in the model organism C. elegans. Using NIR light allows for superior tissue penetration to manipulate neuronal activities and locomotion behavior. For complete details on the use and execution of this protocol, please refer to Guo et al.,1 Ao et al.,2 and Zhang et al.3.

Dynamic control of contractile resistance to iPSC-derived micro-heart muscle arrays.

Many types of cardiovascular disease are linked to the mechanical forces placed on the heart. However, our understanding of how mechanical forces exactly affect the cellular biology of the heart remains incomplete. In vitro models based on cardiomyocytes derived from human induced pluripotent stem cells (iPSC-CM) enable researchers to develop medium to high-throughput systems to study cardiac mechanobiology at the cellular level. Previous models have been developed to enable the study of mechanical forces, such as cardiac afterload. However, most of these models require exogenous extracellular matrix (ECM) to form cardiac tissues. Recently, a system was developed to simulate changes in afterload by grafting ECM-free micro-heart muscle arrays to elastomeric substrates of discrete stiffnesses. In the present study, we extended this system by combining the elastomer-grafted tissue arrays with a magnetorheological elastomeric substrate. This system allows iPSC-CM based micro-heart muscle arrays to experience dynamic changes in contractile resistance to mimic dynamically altered afterload. Acute changes in substrate stiffness led to acute changes in the calcium dynamics and contractile forces, illustrating the system's ability to dynamically elicit changes in tissue mechanics by dynamically changing contractile resistance.

Developing a Two-Photon "AND" Logic Probe and Its Application in Alzheimer's Disease Differentiation.

In Alzheimer's disease, hypochlorous acid involved in the clearance of invading bacteria or pathogens and butyrylcholinesterase engaged in the hydrolysis of the neurotransmitter acetylcholine are relatively significantly altered. However, there are few dual detection probes for hypochlorous acid and butyrylcholinesterase. In addition, single-response probes suffer from serious off-target effects and near-infrared probes do not easily penetrate the blood-brain barrier due to their excessive molecular weight. In this work, we constructed a two-photon fluorescent probe that recognizes hypochlorous acid and butyrylcholinesterase based on a dual-lock strategy. The thiocarbonyl group is oxidized in the presence of hypochlorous acid, and the hydrolysis occurs at the 7-position ester bond in the existence of butyrylcholinesterase, releasing a strongly fluorescent fluorophore, 4-methylumbelliferone. Excellent imaging was performed in PC12 cells using this probe, and deep two-photon imaging was observed in the brains of AD mice after tail vein injection with this probe. It indicates that the probe can provide a promising tool for the more precise diagnosis of Alzheimer's disease.

Mechanical Resistance to Micro-Heart Tissue Contractility unveils early Structural and Functional Pathology in iPSC Models of Hypertrophic Cardiomyopathy.

Hypertrophic cardiomyopathy is the most common cause of sudden death in the young. Because the disease exhibits variable penetrance, there are likely nongenetic factors that contribute to the manifestation of the disease phenotype. Clinically, hypertension is a major cause of morbidity and mortality in patients with HCM, suggesting a potential synergistic role for the sarcomeric mutations associated with HCM and mechanical stress on the heart. We developed an in vitro physiological model to investigate how the afterload that the heart muscle works against during contraction acts together with HCM-linked MYBPC3 mutations to trigger a disease phenotype. Micro-heart muscle arrays (µHM) were engineered from iPSC-derived cardiomyocytes bearing MYBPC3 loss-of-function mutations and challenged to contract against mechanical resistance with substrates stiffnesses ranging from the of embryonic hearts (0.4 kPa) up to the stiffness of fibrotic adult hearts (114 kPa). Whereas MYBPC3 +/- iPSC-cardiomyocytes showed little signs of disease pathology in standard 2D culture, µHMs that included components of afterload revealed several hallmarks of HCM, including cellular hypertrophy, impaired contractile energetics, and maladaptive calcium handling. Remarkably, we discovered changes in troponin C and T localization in the MYBPC3 +/- µHM that were entirely absent in 2D culture. Pharmacologic studies suggested that excessive Ca 2+ intake through membrane-embedded channels, rather than sarcoplasmic reticulum Ca 2+ ATPase (SERCA) dysfunction or Ca 2+ buffering at myofilaments underlie the observed electrophysiological abnormalities. These results illustrate the power of physiologically relevant engineered tissue models to study inherited disease mechanisms with iPSC technology.

Porphyrin-anthracene covalent organic frameworks for sustainable photosterilization.

Covalent organic frameworks (COFs) have promising applications in enhanced phototherapy. However, COFs that can sustainably play a role in phototherapy without continuous irradiation are extremely scarce. Herein, we report the fabrication of porphyrin-anthracene multifunctional COFs (Por-DPA) for sustainable photosterilization and bacterial-infected wound healing. A porphyrin photosensitizer, as one of the monomers, was used to provide photothermal and photodynamic activities under irradiation. An anthracene derivative, a good chemical source of singlet oxygen (1O2), was selected as another monomer to capture 1O2 and release it continuously via cycloreversion in the dark. The prepared Por-DPA COF prevents the self-aggregation quenching of the photosensitizer and thermal damage caused by continuous exposure to external light sources. Besides, Por-DPA exhibits good photothermal conversion performance and efficient 1O2 production capacity through dual pathways of photosensitization and cycloreversion. The developed sustainable photosterilization platform not only has good bactericidal effects on Escherichia coli and Staphylococcus aureus, but also promotes wound healing without obvious side effects, and is expected to be a novel efficient bactericide.

Virtual blebbistatin: A robust and rapid software approach to motion artifact removal in optical mapping of cardiomyocytes.

Fluorescent reporters of cardiac electrophysiology provide valuable information on heart cell and tissue function. However, motion artifacts caused by cardiac muscle contraction interfere with accurate measurement of fluorescence signals. Although drugs such as blebbistatin can be applied to stop cardiac tissue from contracting by uncoupling calcium-contraction, their usage prevents the study of excitation-contraction coupling and, as we show, impacts cellular structure. We therefore developed a robust method to remove motion computationally from images of contracting cardiac muscle and to map fluorescent reporters of cardiac electrophysiological activity onto images of undeformed tissue. When validated on cardiomyocytes derived from human induced pluripotent stem cells (iPSCs), in both monolayers and engineered tissues, the method enabled efficient and robust reduction of motion artifact. As with pharmacologic approaches using blebbistatin for motion removal, our algorithm improved the accuracy of optical mapping, as demonstrated by spatial maps of calcium transient decay. However, unlike pharmacologic motion removal, our computational approach allowed direct analysis of calcium-contraction coupling. Results revealed calcium-contraction coupling to be more uniform across cells within engineered tissues than across cells in monolayer culture. The algorithm shows promise as a robust and accurate tool for optical mapping studies of excitation-contraction coupling in heart tissue.

Bidirectional near-infrared regulation of motor behavior using orthogonal emissive upconversion nanoparticles.

Bidirectional optogenetic manipulation enables specific neural function dissection and animal behaviour regulation with high spatial-temporal resolution. It relies on the respective activation of two or more visible-light responsive optogenetic sensors, which inevitably induce signal crosstalk due to their spectral overlap, low photoactivation efficiency and potentially high biotoxicity. Herein, a strategy that combines dual-NIR-excited orthogonal emissive upconversion nanoparticles (OUCNPs) with a single dual-colour sensor, BiPOLES, is demonstrated to achieve bidirectional, crosstalk-free NIR manipulation of motor behaviour in vivo. Core@shell-structured OUCNPs with Tm3+ and Er3+ dopants in isolated layers exhibit orthogonal blue and red emissions in response to excitation at 808 and 980 nm, respectively. The OUCNPs subsequently activate BiPOLES-expressing excitatory cholinergic motor neurons in C. elegans, leading to significant inhibition and excitation of motor neurons and body bends, respectively. Importantly, these OUCNPs exhibit negligible toxicity toward neural development, motor function and reproduction. Such an OUCNP-BiPOLES system not only greatly facilitates independent, bidirectional NIR activation of a specific neuronal population and functional dissection, but also greatly simplifies the bidirectional NIR optogenetics toolset, thus endowing it with great potential for flexible upconversion optogenetic manipulation.

Exogenous interference and autofluorescence-free ratiometric aptasensor for detection of OTA based on dual-colored persistent luminescence nanoparticles.

Accurate and sensitive detection of ochratoxin A (OTA) is highly necessary due to its high carcinogenicity, teratogenicity and mutagenicity. Herein, we reported an exogenous interference and autofluorescence-free ratiometric aptasensor based on dual-colored persistent luminescent nanoparticles for precise detection of OTA. Green-emitting ZnGeO:Mn bonded with OTA aptamer and BHQ1-modified complementary base was acted as detection and specific recognition probe (ZGM@BHQ1). Quaternary ammonium modified ZnGaGeO:Cr with red emission was employed as reference probe and further bonded to ZGM@BHQ1 through electrostatic interaction to construct the ratiometric aptasensor. The developed ratiometric aptasensor was free from real-time excitation, external interference and autofluorescence and gave low detection limit of 3.4 pg mL-1, wide linearity in the range of 0.01-50 ng mL-1 and high precision of 3.1 % (11 replicate determinations, at 1 ng mL-1 level). The applicability of the aptasensor was successfully demonstrated by analyzing OTA in in grain samples with recoveries of 97.6 %-105.2 %.

Acrylate-functionalized porphyrin-covalent organic framework for bacterial-targeted and reaction-enhanced synergistic phototherapy/chemotherapy toward sterilization and wound healing.

Porphyrinic covalent organic frameworks (COFs) have emerged as prospective materials in photodynamic and photothermal sterilization. However, it is still a great challenge to construct an efficient COF-based sterilizing agent with good photothermal and photodynamic properties and bacterial targeting ability. Herein, we report a multifunctional porphyrin-COF for bacterial-targeted and reaction-enhanced synergistic phototherapy/chemotherapy for sterilization and wound healing. The ordered crystal structure of the porphyrin-COF not only effectively avoids the self-aggregation-induced quenching of the porphyrin monomer, but also facilitates the storage and transport of singlet oxygen. The acrylate substituent in the other monomer serves as a bacterial targeting moiety and the in situ reaction site with the sulfhydryl group of the bacterial surface protein via a Michael addition reaction, thus fixing the bacteria on the surface of COF and making them lose the colonization ability. Furthermore, the bonding of COF and bacteria further amplifies the therapeutic efficiency of phototherapy. Therefore, the developed multifunctional sterilization platform not only provides a new strategy for the design of novel bactericidal materials but also broadens the biological applications of COF-based materials.

Choice reaction time in pigeons fails to increase as predicted by Hick's law.

Being able to correctly identify a target when presented with multiple possible alternatives, or increasing uncertainty, is highly beneficial in a wide variety of situations. This has been intensely investigated with human participants and results consistently demonstrated that participant reaction time (RT) increases linearly with the number of response alternatives, described as Hick's Law. Yet, the strength of this relationship is impacted by a variety of parameters, including stimulus-response compatibility, stimulus intensity, and practice. Different theories attempt to explain why these parameters affect the time to detect the target, but thus far these theories almost exclusively rely on human and nonhuman primate research. Therefore, it is unclear if these theories are universal or unique to primates, due to the scarcity of other animal models. A previous investigation showed that pigeon RT will increase in accordance with Hick's Law though not as steeply as human RT, potentially due to differences in the procedure used on pigeons. To better understand pigeon RT under uncertainty and facilitate cross species comparisons, these experiments used a procedure that was more similar to what has been given to humans. Surprisingly, pigeon RT did not follow Hick's Law as predicted. In Experiment 1, subjects showed an 'anti-Hick's' effect due to an artefact of stimulus location on the monitor. Subsequent experiments controlled for location, still RT did not increase with the number of choices as predicted by Hick's Law. Procedural changes that may have been responsible for this difference and the role of stimulus-response compatibility are discussed.

Potential of fluorescent nanoprobe in diagnosis and treatment of Alzheimer's disease.

Alzheimer's disease (AD) is well known for its insidious nature, slow progression and high incidence as a neurodegenerative disease. In the past, diagnosis of AD mainly depended on analysis of a patient's cognitive ability and behavior. Without a unified standard for analysis methods, this is prone to produce incorrect diagnoses. Currently, definitive diagnosis mainly relies on histopathological examination. Because of the advantages of precision, noninvasiveness, low toxicity and high spatiotemporal resolution, fluorescent nanoprobes are suitable for the early diagnosis of AD. This review summarizes the research progress of different kinds of fluorescent nanoprobes for AD diagnosis and therapy in recent years and provides an outlook on the development prospects of fluorescent nanoprobes.

Tonoplast-localized transporter ZmNRAMP2 confers root-to-shoot translocation of manganese in maize.

Almost all living organisms require manganese (Mn) as an essential trace element for survival. To maintain an irreplaceable role in the oxygen-evolving complex of photosynthesis, plants require efficient Mn uptake in roots and delivery to above-ground tissues. However, the underlying mechanisms of root-to-shoot Mn translocation remain unclear. Here, we identified an Natural Resistance Associated Macrophage Protein (NRAMP) family member in maize (Zea mays), ZmNRAMP2, which localized to the tonoplast in maize protoplasts and mediated transport of Mn in yeast (Saccharomyces cerevisiae). Under Mn deficiency, two maize mutants defective in ZmNRAMP2 exhibited remarkable reduction of root-to-shoot Mn translocation along with lower shoot Mn contents, resulting in substantial decreases in Fv/Fm and plant growth inhibition compared to their corresponding wild-type (WT) plants. ZmNRAMP2 transcripts were highly expressed in xylem parenchyma cells of the root stele. Compared to the WT, the zmnramp2-1 mutant displayed lower Mn concentration in xylem sap accompanied with retention of Mn in root stele. Furthermore, the overexpression of ZmNRAMP2 in transgenic maize showed enhanced root-to-shoot translocation of Mn and improved tolerance to Mn deficiency. Taken together, our study reveals a crucial role of ZmNRAMP2 in root-to-shoot translocation of Mn via accelerating vacuolar Mn release in xylem parenchyma cells for adaption of maize plants to low Mn stress and provides a promising transgenic approach to develop low Mn-tolerant crop cultivars.

Robust, Automated Analysis of Electrophysiology in Induced Pluripotent Stem Cell-Derived Micro-Heart Muscle for Drug Toxicity.

Drugs are often removed from clinical trials or market progression owing to their unforeseen effects on cardiac action potential and calcium handling. Induced pluripotent stem cell-derived cardiomyocytes and tissues fabricated from these cells are promising as screening tools for early identification of these potential cardiac liabilities. In this study, we describe an automated, open-source MATLAB-based analysis software for calculating cardiac action potentials and calcium transients from fluorescent reporters. We first identified the most robust manner in which to automatically identify the initiation point for action potentials and calcium transients in a user-independent manner, and used this approach to quantify the duration and morphology of these signals. We then demonstrate the software by assessing changes to action potentials and calcium transients in our micro-heart muscles after exposure to hydroxychloroquine, an antimalarial drug with known cardiac liability. Consistent with clinical observations, our system predicted mild action potential prolongation. However, we also observed marked calcium transient suppression, highlighting the advantage of testing multiple physiologic readouts in cardiomyocytes rather than relying on heterologous overexpression of single channels such as the human ether-a-go-go-related gene channel. This open-source software can serve as a useful, high-throughput tool for analyzing cardiomyocyte physiology from fluorescence imaging.

Perioperative Acupuncture Optimizes Surgical Outcomes: Theory, Clinical Practice and Future Perspectives.

A growing body of evidence supports the use of perioperative acupuncture as part of an enhanced postsurgical recovery protocol. Data from both clinical trials and animal studies has shown that the integration of acupuncture into perioperative patient care leads to a reduction of perioperative complications such as preoperative anxiety, intraoperative hemodynamic instability, postoperative pain, postoperative cognitive dysfunction, and postoperative nausea and vomiting in surgical patients. Despite these favorable outcomes, perioperative acupuncture has yet to be widely adopted in current anesthesia practice. This review summarized data from clinical perioperative acupuncture studies and cites recent discoveries regarding the anatomical location and characteristics of acupoint(s), acupuncture stimulation techniques, and treatment practice protocols, as well as identified the areas of deficiency in perioperative acupuncture applications. To facilitate acupuncture integration in perioperative care practice, the authors propose to establish a perioperative acupuncture registry which can be used for data mining as well as a resource for studying the underlying mechanisms of acupuncture. Through this acupuncture registry, clinical guidelines and research protocols can be established, additional large/multi-center clinical and pragmatic trials can be easily performed to determine if the integration and expansion of perioperative acupuncture practice is cost-effective.

Interplay of Genotype and Substrate Stiffness in Driving the Hypertrophic Cardiomyopathy Phenotype in iPSC-Micro-Heart Muscle Arrays.

INTRODUCTION: In clinical and animal studies, Hypertrophic Cardiomyopathy (HCM) shares many similarities with non-inherited cardiac hypertrophy induced by pressure overload (hypertension). This suggests a potential role for mechanical stress in priming tissues with mutation-induced changes in the sarcomere to develop phenotypes associated with HCM, including hypercontractility and aberrant calcium handling. Here, we tested the hypothesis that heterozygous loss of function of Myosin Binding Protein C (MYBCP3 +/- , mutations in which account for almost 50% of inherited HCM) combines with environmental stiffness to drive HCM phenotypes. METHODS: We differentiated isogenic control (WTC) and MYBPC3 +/- iPSC into cardiomyocytes using small molecule manipulation of Wnt signaling, and then purified them using lactate media. The purified cardiomyocytes were seeded into "dog bone" shaped stencil molds to form micro-heart muscle arrays (µHM). To mimic changes in myocardial stiffness stemming from pressure overload, we varied the rigidity of the substrates µHM contract against. Stiffness levels ranged from those corresponding to fetal (5 kPa), healthy (15 kPa), pre-fibrotic (30 kPa) to fibrotic (65 kPa) myocardium. Substrates were embedded with a thin layer of fluorescent beads to track contractile force, and parent iPSC were engineered to express the genetic calcium indicator, GCaMP6f. High speed video microscopy and image analysis were used to quantify calcium handling and contractility of µHM. RESULTS: Substrate rigidity triggered physiological adaptation for both genotypes. However, MYBPC3 +/- µHM showed a lower tolerance to substrate stiffness with the peak traction on 15 kPa, while WTC µHM had peak traction on 30 kPa. MYBPC3 +/- µHM exhibited hypercontractility, which was exaggerated by substrate rigidity. MYBPC3 +/- µHM hypercontractility was associated with longer rise times for calcium uptake and force development, along with higher overall Ca2+ intake. CONCLUSION: We found MYBPC3 +/- mutations cause iPSC-µHM to exhibit hypercontractility, and also a lower tolerance for mechanical stiffness. Understanding how genetics work in combination with mechanical stiffness to trigger and/or exacerbate pathophysiology may lead to more effective therapies for HCM. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at (10.1007/s12195-021-00684-x).

Biocompatible and Enzymatically Degradable Gels for 3D Cellular Encapsulation under Extreme Compressive Strain.

Cell encapsulating scaffolds are necessary for the study of cellular mechanosensing of cultured cells. However, conventional scaffolds used for loading cells in bulk generally fail at low compressive strain, while hydrogels designed for high toughness and strain resistance are generally unsuitable for cell encapsulation. Here we describe an alginate/gelatin methacryloyl interpenetrating network with multiple crosslinking modes that is robust to compressive strains greater than 70%, highly biocompatible, enzymatically degradable and able to effectively transfer strain to encapsulated cells. In future studies, this gel formula may allow researchers to probe cellular mechanosensing in bulk at levels of compressive strain previously difficult to investigate.