An Acoustofluidic Picoinjector.

Droplet microfluidics has emerged as a valuable technology for a multitude of chemical and biomedical applications, offering the capability to create independent microenvironments for high-throughput assays. Central to numerous droplet microfluidic applications is the picoinjection of materials into individual droplets, yet existing picoinjection methods often exhibit high power requirements, lack biocompatibility, and/or suffer from limited controllability. Here, we present an acoustofluidic picoinjector that generates acoustic pressure at the droplet interface to enable on-demand, energy-efficient, and biocompatible injection at high precision. We validate our platform by performing acid-base titrations by iteratively injecting picoliter volume reagents into droplets to induce pH transitions detectable by color change in solution. Additionally, we demonstrate the versatility of the acoustofluidic picoinjector in the synthesis of metallic nanoparticles, yielding highly monodisperse and reproducible particle morphologies compared to conventional bulk-phase techniques. By facilitating controlled delivery of reagents or biological samples with unparalleled accuracy, acoustofluidic picoinjection broadens the utility of droplet microfluidics for a myriad of applications in chemical and biological research.

Harmonic acoustics for dynamic and selective particle manipulation.

Precise and selective manipulation of colloids and biological cells has long been motivated by applications in materials science, physics and the life sciences. Here we introduce our harmonic acoustics for a non-contact, dynamic, selective (HANDS) particle manipulation platform, which enables the reversible assembly of colloidal crystals or cells via the modulation of acoustic trapping positions with subwavelength resolution. We compose Fourier-synthesized harmonic waves to create soft acoustic lattices and colloidal crystals without using surface treatment or modifying their material properties. We have achieved active control of the lattice constant to dynamically modulate the interparticle distance in a high-throughput (>100 pairs), precise, selective and reversible manner. Furthermore, we apply this HANDS platform to quantify the intercellular adhesion forces among various cancer cell lines. Our biocompatible HANDS platform provides a highly versatile particle manipulation method that can handle soft matter and measure the interaction forces between living cells with high sensitivity.

Ring-shaped photoacoustic tweezers for single particle manipulation.

This Letter reports ring-shaped photoacoustic (PA) tweezers that are capable of manipulating single or multiple micron-sized particles. By illuminating a thin layer of an optically absorptive liquid medium with a focused annular pulsed laser beam and a higher pulse repetition rate (e.g., 800 Hz), both acoustic radiation force and instantaneous vaporization repulsion are generated within a certain distance of the illumination region. This makes it possible to conduct continuous and versatile locomotion of single or multiple microparticles. In this Letter, interactions between two or more particles are demonstrated, such as separation, attachment, and grouping of microparticles. The PA tweezers combine some of the advantages of conventional optical and acoustic tweezers and are expected to be a useful alternative approach for the manipulation of microscale objects.

First Report of Root Rot Caused by Phytophthora acerina on Metasequoia glyptostroboides in China.

Metasequoia glyptostroboides Hu & W. C. Cheng (Taxodiaceae), commonly called the Chinese redwood or dawn redwood, is a well-known "living fossil" and rare relict plant species endemic to China, which has been successfully cultivated throughout the world (Ma 2007). In July to September 2020, trees of Chinese redwood which were more than thirty years-old, showed symptoms of decline and death associated with branch dieback, root and collar rot (Fig. 1) in Yangtze River shelter-forests of Jiangling County in Hubei Province, China (112°15'19″E, 30°11'56″N; 40m). Diseased roots and rhizosphere soils were collected in September 2020 and April 2021. Using the baiting method, a homothallic Phytophthora sp. was recovered consistently from diseased roots and soil samples of Chinese redwood. All the isolates of this Phytophthora sp. formed similar colonies on V8 agar and corn meal agar (Fig. 2), and then three representative isolates (L4-5-4, L4-5-5 and L4-5-6) were randomly selected for morphological and molecular identification. In distilled water, semipapillate persistent sporangia were borne in simple sympodial branched sporangiophores. Sporangia were predominantly ovoid (Fig. 3a, d and f), but other shapes were observed including subglobose (Fig. 3b), limoniform (Fig. 3c) or distorted shapes (Fig. 3e), averaging 44.1 ± 7.7 µm (n=102) in length and 32.8 ± 5.2 µm (n=102) in width, with narrow exit pores of 8.0 ± 1.4 µm (n=93) and a length/breadth ratio of 1.3 ± 0.10 (n=102). Chlamydospores were not observed. Oogonia were globose or subglobose, 20.51 to 40.15 µm (av. 33.1 ± 3.9 µm) (n=119) in diameter, with smooth walls and paragynous antheridium (Fig. 3g-i). Oospores were globose or subglobose in elongated oogonia with medium wall thickness of 1.9 ± 0.5 µm (n=36), aplerotic or plerotic and 16.9 to 32.6 µm in diameter (av. 26.6 ± 3.8 µm) (n=40). According to the above morphological characteristics, this Phytophthora sp. was placed in Waterhouse's (1963) group III. The sequences of the internal transcribed spacers (ITS) region of nuclear ribosomal DNA of each isolate (GenBank Accession No. OK087320, OK087321 and OK087322) was 760 bp and had identity of 99.84% with three P. acerina isolates (JX951285, JX951291 and JX951296), while the 800 bp ß-tubulin (BTUB) sequences (OK140540, OK140541 and OK140542) showed 99.97% homology to the sequence of P. acerina (KC201283) (Ginetti, Moricca and Squires 2014) (Table 1). The ML phylogenetic trees were established by comparing ITS and BTUB sequences of three Phytophthora strains (L4-5-4, L4-5-5 and L4-5-6) with reference sequences of isolates of Phytophthora in ITS and BTUB in GenBank (Fig. 4-5). Based on the morphological and molecular characteristics, the strains were identified as namely P. acerina. In addition, pathogenicity assays were performed with one of the three strains (L4-5-4) on M. glyptostroboides using both one year old and three years old seedlings. Inoculum was prepared by subculturing agar plugs from edges of CMA cultures into V8 medium plates, incubating at 20 ℃ in darkness for 10 days. Six seedlings planted in pots filled with sterilized soil were inoculated by mycelium plug at root collar and stem wounded by a 8 mm diameter puncher. Six control seedlings were inoculated in the same manner as above, and sterile agar plugs were used. After 35 days, inoculated seedlings all had necrotic lesions at the inoculation sites, and some seedlings had the symptoms of foliage blight and dieback, whereas control seedlings remained healthy (Fig. 6). The number of fibrous roots after inoculation was significantly less than the control, and the roots of inoculated seedlings blackened or even rotted, while there were no obvious symptoms in the control (Fig. 7). Phytophthora isolates recovered from the symptomatic tissues of artificially inoculated plants were identical to isolate L4-5-4 in morphological characters and ITS sequencing. This is the first report of P. acerina causing root rot on the Chinese redwood in China. As only the seedlings were inoculated, further research is needed to address the epidemiology and pathogenicity of P. acerina to adult trees of Chinese red wood. References: Ginetti, B. et al. 2014. Plant Pathology, 63(4): 858-876. Ma, J. S. 2007. Bulletin of the Peabody Museum of Natural History, 48(2): 235-253. Waterhouse, G. M. 1963. Mycological Papers 92:1-22.

Acoustofluidic Droplet Sorter Based on Single Phase Focused Transducers.

Droplet microfluidics has revolutionized the biomedical and drug development fields by allowing for independent microenvironments to conduct drug screening at the single cell level. However, current microfluidic sorting devices suffer from drawbacks such as high voltage requirements (e.g., >200 Vpp), low biocompatibility, and/or low throughput. In this article, a single-phase focused transducer (SPFT)-based acoustofluidic chip is introduced, which outperforms many microfluidic droplet sorting devices through high energy transmission efficiency, high accuracy, and high biocompatibility. The SPFT-based sorter can be driven with an input power lower than 20 Vpp and maintain a postsorting cell viability of 93.5%. The SPFT sorter can achieve a throughput over 1000 events per second and a sorting purity up to 99.2%. The SPFT sorter is utilized here for the screening of doxorubicin cytotoxicity on cancer and noncancer cells, proving its drug screening capability. Overall, the SPFT droplet sorting device shows great potential for fast, precise, and biocompatible drug screening.

Effects of Cognitive Behavioral Therapy on Pain and Sleep in Adults with Traumatic Brain Injury: A Systematic Review and Meta-Analysis.

The objective of this study was to systematically review the literature on the effects of cognitive behavioral therapy (CBT) on insomnia and pain in patients with traumatic brain injury (TBI). PubMed, Embase, the Cochrane Library, Cumulative Index to Nursing and Allied Health, and Web of Science databases were searched. Outcomes, including pain, sleep quality, and adverse events, were investigated. Differences were expressed using mean differences (MDs) with 95% confidence intervals (CIs). The statistical analysis was performed using STATA 16.0. Twelve trials with 476 TBI patients were included. The included studies did not indicate a positive effect of CBT on pain. Significant improvements were shown for self-reported sleep quality, reported with the Pittsburgh Self-Reported Sleep Quality Index (MD, -2.30; 95% CI, -3.45 to -1.15; P < 0.001) and Insomnia Severity Index (MD, -5.12; 95% CI, -9.69 to -0.55; P = 0.028). No major adverse events related to CBT were reported. The underpowered evidence suggested that CBT is effective in the management of sleep quality and pain in TBI adults. Future studies with larger samples are recommended to determine significance. This trial is registered with PROSPERO registration number CRD42019147266.

Impact of COVID-19 on Emotional Resilience and Learning Management of Middle School Students.

BACKGROUND The aim of this study was to explore the emotional resilience of middle school students learning at home in February and March 2020 during the COVID-19 pandemic, and the impact of this resilience on students' learning management skills. The results could provide a basis for psychological health education of middle school students during major life events. MATERIAL AND METHODS This study used a survey to explore emotional resilience and learning management abilities in middle school students (N=896) from February 10, 2020, to March 22, 2020. Students used online e-learning during this period due to the COVID-19 pandemic. Data were analyzed using t-testing, Pearson's correlation, and multivariate linear regression. RESULTS The results indicate that emotional resilience was significantly lower in eighth grade students than in seventh grade students (t=1.98, P<0.05) and negative emotional recovery increased during the study period. Emotional resilience was positively correlated with learning management skills (r=0.498, P<0.01), and positive emotional ability predicted learning management skills. CONCLUSIONS The study findings indicate that in the face of major life events, emotional resilience is an important factor for the mental health of adolescents and improves coping ability. Cultivating positive emotions can improve learning efficiency.

The anti-inflammatory and anti-oxidative effects of conbercept in treatment of macular edema secondary to retinal vein occlusion.

To investigate the effects of conbercept on inflammatory and oxidative response in macular edema secondary to retinal vein occlusion (RVO-ME). Retinal microvasculature were detected by optical coherence tomographic angiography (OCTA). The inflammation related factors including prostaglandin E1 (PGE1), prostaglandin E2 (PGE2), prostaglandin F2a (PGF2a), intercellular cell adhesion molecule-1 (ICAM-1) and macrophage inflammatory protein-1 (MIP-1) were determined in human and mice with RVO-ME. OCTA images showed that capillary non-perfusion, enlargement of the foveal avascular zone, telangiectatic vessels and some forms of intraretinal edema in RVO-ME and all these were alleviated by conbercept treatment. PGE1, PGE2, PGF2a, ICAM-1 and MIP-1 in aqueous fluid extracted from RVO-ME patients was significantly increased compared with non-RVO subjects, intravitreal injection of conbercept partly reduced ICAM-1 and MIP-1 levels but not PGE1, PGE2 and PGF2a. The glutathione level was reduced in aqueous fluid extracted from RVO-ME patients but was restored after conbercept treatment. The inflammation, angiogenesis and ROS generation was increased in RVO-ME mice, conbercept partly inhibited these effects. Mechanistically, conbercept inhibited vascular endothelial growth factor (VEGF), ICAM-1, MIP-1, NOX-1 and NOX-4 protein expressions, but not PGE1, PGE2 and PGF2a expressions. Conbercept alleviates RVO-ME through inhibiting inflammation, angiogenesis and oxidative responses. These findings further reveals the molecular mechanism of conbercept for treatment of RVO-ME.

Prevalence and genotype distribution of HPV infection from Hangzhou of Zhejiang Province pre- and during COVID-19 pandemic.

Limited data exist on HPV prevalence and genotyping during the COVID-19 pandemic. A total of 130,243 samples from 129, 652 women and 591 men who visited the First People's Hospital of Linping District between 2016 and 2022 were recruited. HPV genotypes were detected by polymerase chain reaction (PCR) amplification and nucleic acid molecular hybridization. Then the prevalence characteristics of HPV genotypes and trends in HPV infection rates from 2016 to 2022 were analyzed. Results showed that among the study population, the overall prevalence of HPV infection was 15.29%, with 11.25% having single HPV infections and 4.04% having multiple HPV infections, consistent with previous findings. HPV genotypes exhibited similar distribution patterns in both male and female groups, with HPV16, HPV52, HPV58, HPV18, and HPV39 being the most prevalent. Age-related analysis unveiled a bimodal pattern in HPV prevalence, with peaks in infection rates observed in individuals below 20 and those aged 61-65 years. Comparing the pre- and during COVID-19 periods revealed significant disparities in HPV infections, with variations in specific HPV genotypes, including 16, 18, 35, 45, 52, 58, 59, and 68. This study provides valuable insights into the prevalence, distribution, and epidemiological characteristics of HPV infections in a large population. It also highlights the potential impact of the COVID-19 pandemic on HPV trends.

Acoustofluidic scanning fluorescence nanoscopy with a large field of view.

Large-field nanoscale fluorescence imaging is invaluable for many applications, such as imaging subcellular structures, visualizing protein interactions, and high-resolution tissue imaging. Unfortunately, conventional fluorescence microscopy requires a trade-off between resolution and field of view due to the nature of the optics used to form the image. To overcome this barrier, we developed an acoustofluidic scanning fluorescence nanoscope that simultaneously achieves superior resolution, a large field of view, and strong fluorescent signals. The acoustofluidic scanning fluorescence nanoscope utilizes the superresolution capabilities of microspheres that are controlled by a programmable acoustofluidic device for rapid fluorescence enhancement and imaging. The acoustofluidic scanning fluorescence nanoscope resolves structures that cannot be resolved with conventional fluorescence microscopes with the same objective lens and enhances the fluorescent signal by a factor of ~5 without altering the field of view of the image. The improved resolution realized with enhanced fluorescent signals and the large field of view achieved via acoustofluidic scanning fluorescence nanoscopy provides a powerful tool for versatile nanoscale fluorescence imaging for researchers in the fields of medicine, biology, biophysics, and biomedical engineering.

YouTube as a source of information for cryptococcal infection: A cross-sectional study.

Objective: Immunocompromised individuals, particularly HIV patients, worldwide are at risk from cryptococcal infection. There are a number of videos of cryptococcal infection and more and more individuals may search these videos, but the quality of videos on YouTube is unclear. This study set out to assess the content and quality of YouTube videos regarding cryptococcal infection. Methods: The keywords "Cryptococcus," "Cryptococcosis" and "Cryptococcal infection" were searched on YouTube. The videos were evaluated and graded by two impartial raters. A 14-point content score was used to categorize videos as bad, good or exceptional. The reliability and quality were evaluated utilizing the DISCERN instrument and a 5-point global quality score. Videos were then divided into groups based on uploading sources and content types. Results: A total of 46 videos were located, and the ratings provided by the two raters were identical. Our scoring algorithm determined that 54.3% (n = 25), 32.6% (n = 15) and 13.0% (n = 6) of the videos were poor, decent and exceptional, respectively. Regarding quality, no difference was identified between the various video categories. The global quality scale, number of views, days posted, content score and DISCERN showed a significant positive relationship. Conclusions: Professional individuals or healthcare organizations should be encouraged to submit high-quality videos for the expanding internet population, as only a small proportion of available videos had exceptional quality.

An acoustofluidic device for the automated separation of platelet-reduced plasma from whole blood.

Separating plasma from whole blood is an important sample processing technique required for fundamental biomedical research, medical diagnostics, and therapeutic applications. Traditional protocols for plasma isolation require multiple centrifugation steps or multiunit microfluidic processing to sequentially remove large red blood cells (RBCs) and white blood cells (WBCs), followed by the removal of small platelets. Here, we present an acoustofluidic platform capable of efficiently removing RBCs, WBCs, and platelets from whole blood in a single step. By leveraging differences in the acoustic impedances of fluids, our device generates significantly greater forces on suspended particles than conventional microfluidic approaches, enabling the removal of both large blood cells and smaller platelets in a single unit. As a result, undiluted human whole blood can be processed by our device to remove both blood cells and platelets (>90%) at low voltages (25 Vpp). The ability to successfully remove blood cells and platelets from plasma without altering the properties of the proteins and antibodies present creates numerous potential applications for our platform in biomedical research, as well as plasma-based diagnostics and therapeutics. Furthermore, the microfluidic nature of our device offers advantages such as portability, cost efficiency, and the ability to process small-volume samples.

Acousto-dielectric tweezers enable independent manipulation of multiple particles.

Acoustic tweezers have gained substantial interest in biology, engineering, and materials science for their label-free, precise, contactless, and programmable manipulation of small objects. However, acoustic tweezers cannot independently manipulate multiple microparticles simultaneously. This study introduces acousto-dielectric tweezers capable of independently manipulating multiple microparticles and precise control over intercellular distances and cyclical cell pairing and separation for detailed cell-cell interaction analysis. Our acousto-dielectric tweezers leverage the competition between acoustic radiation forces, generated by standing surface acoustic waves (SAWs), and dielectrophoretic (DEP) forces, induced by gradient electric fields. Modulating these fields allows for the precise positioning of individual microparticles at points where acoustic radiation and DEP forces are in equilibrium. This mechanism enables the simultaneous movement of multiple microparticles along specified paths as well as cyclical cell pairing and separation. We anticipate our acousto-dielectric tweezers to have enormous potential in colloidal assembly, cell-cell interaction studies, disease diagnostics, and tissue engineering.

Acoustofluidic-based therapeutic apheresis system.

Therapeutic apheresis aims to selectively remove pathogenic substances, such as antibodies that trigger various symptoms and diseases. Unfortunately, current apheresis devices cannot handle small blood volumes in infants or small animals, hindering the testing of animal model advancements. This limitation restricts our ability to provide treatment options for particularly susceptible infants and children with limited therapeutic alternatives. Here, we report our solution to these challenges through an acoustofluidic-based therapeutic apheresis system designed for processing small blood volumes. Our design integrates an acoustofluidic device with a fluidic stabilizer array on a chip, separating blood components from minimal extracorporeal volumes. We carried out plasma apheresis in mouse models, each with a blood volume of just 280 µL. Additionally, we achieved successful plasmapheresis in a sensitized mouse, significantly lowering preformed donor-specific antibodies and enabling desensitization in a transplantation model. Our system offers a new solution for small-sized subjects, filling a critical gap in existing technologies and providing potential benefits for a wide range of patients.

Aerosol jet printing of surface acoustic wave microfluidic devices.

The addition of surface acoustic wave (SAW) technologies to microfluidics has greatly advanced lab-on-a-chip applications due to their unique and powerful attributes, including high-precision manipulation, versatility, integrability, biocompatibility, contactless nature, and rapid actuation. However, the development of SAW microfluidic devices is limited by complex and time-consuming micro/nanofabrication techniques and access to cleanroom facilities for multistep photolithography and vacuum-based processing. To simplify the fabrication of SAW microfluidic devices with customizable dimensions and functions, we utilized the additive manufacturing technique of aerosol jet printing. We successfully fabricated customized SAW microfluidic devices of varying materials, including silver nanowires, graphene, and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). To characterize and compare the acoustic actuation performance of these aerosol jet printed SAW microfluidic devices with their cleanroom-fabricated counterparts, the wave displacements and resonant frequencies of the different fabricated devices were directly measured through scanning laser Doppler vibrometry. Finally, to exhibit the capability of the aerosol jet printed devices for lab-on-a-chip applications, we successfully conducted acoustic streaming and particle concentration experiments. Overall, we demonstrated a novel solution-based, direct-write, single-step, cleanroom-free additive manufacturing technique to rapidly develop SAW microfluidic devices that shows viability for applications in the fields of biology, chemistry, engineering, and medicine.

Acoustic separation and concentration of exosomes for nucleotide detection: ASCENDx.

Efficient isolation and analysis of exosomal biomarkers hold transformative potential in biomedical applications. However, current methods are prone to contamination and require costly consumables, expensive equipment, and skilled personnel. Here, we introduce an innovative spaceship-like disc that allows Acoustic Separation and Concentration of Exosomes and Nucleotide Detection: ASCENDx. We created ASCENDx to use acoustically driven disc rotation on a spinning droplet to generate swift separation and concentration of exosomes from patient plasma samples. Integrated plasmonic nanostars on the ASCENDx disc enable label-free detection of enriched exosomes via surface-enhanced Raman scattering. Direct detection of circulating exosomal microRNA biomarkers from patient plasma samples by the ASCENDx platform facilitated a diagnostic assay for colorectal cancer with 95.8% sensitivity and 100% specificity. ASCENDx overcomes existing limitations in exosome-based molecular diagnostics and holds a powerful position for future biomedical research, precision medicine, and point-of-care medical diagnostics.

High-yield and rapid isolation of extracellular vesicles by flocculation via orbital acoustic trapping: FLOAT.

Extracellular vesicles (EVs) have been identified as promising biomarkers for the noninvasive diagnosis of various diseases. However, challenges in separating EVs from soluble proteins have resulted in variable EV recovery rates and low purities. Here, we report a high-yield ( > 90%) and rapid ( < 10 min) EV isolation method called FLocculation via Orbital Acoustic Trapping (FLOAT). The FLOAT approach utilizes an acoustofluidic droplet centrifuge to rotate and controllably heat liquid droplets. By adding a thermoresponsive polymer flocculant, nanoparticles as small as 20 nm can be rapidly and selectively concentrated at the center of the droplet. We demonstrate the ability of FLOAT to separate urinary EVs from the highly abundant Tamm-Horsfall protein, addressing a significant obstacle in the development of EV-based liquid biopsies. Due to its high-yield nature, FLOAT reduces biofluid starting volume requirements by a factor of 100 (from 20 mL to 200 µL), demonstrating its promising potential in point-of-care diagnostics.

Acoustofluidic Virus Isolation via Bessel Beam Excitation Separation Technology.

The isolation of viruses from complex biological samples is essential for creating sensitive bioassays that assess the efficacy and safety of viral therapeutics and vaccines, which have played a critical role during the COVID-19 pandemic. However, existing methods of viral isolation are time-consuming and labor-intensive due to the multiple processing steps required, resulting in low yields. Here, we introduce the rapid, efficient, and high-resolution acoustofluidic isolation of viruses from complex biological samples via Bessel beam excitation separation technology (BEST). BEST isolates viruses by utilizing the nondiffractive and self-healing properties of 2D, in-plane acoustic Bessel beams to continuously separate cell-free viruses from biofluids, with high throughput and high viral RNA yield. By tuning the acoustic parameters, the cutoff size of isolated viruses can be easily adjusted to perform dynamic, size-selective virus isolation while simultaneously trapping larger particles and separating smaller particles and contaminants from the sample, achieving high-precision isolation of the target virus. BEST was used to isolate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from human saliva samples and Moloney Murine Leukemia Virus from cell culture media, demonstrating its potential use in both practical diagnostic applications and fundamental virology research. With high separation resolution, high yield, and high purity, BEST is a powerful tool for rapidly and efficiently isolating viruses. It has the potential to play an important role in the development of next-generation viral diagnostics, therapeutics, and vaccines.

Acoustofluidic scanning fluorescence nanoscopy with large field of view.

Nanoscale fluorescence imaging with a large-field view is invaluable for many applications such as imaging of subcellular structures, visualizing protein interaction, and high-resolution tissue imaging. Unfortunately, conventional fluorescence microscopy has to make a trade-off between resolution and field of view due to the nature of the optics used to form an image. To overcome this barrier, we have developed an acoustofluidic scanning fluorescence nanoscope that can simultaneously achieve superior resolution, a large field of view, and enhanced fluorescent signal. The acoustofluidic scanning fluorescence nanoscope utilizes the super-resolution capability of microspheres that are controlled by a programable acoustofluidic device for rapid fluorescent enhancement and imaging. The acoustofluidic scanning fluorescence nanoscope can resolve structures that cannot be achieved with a conventional fluorescent microscope with the same objective lens and enhances the fluorescent signal by a factor of ~5 without altering the field of view of the image. The improved resolution with enhanced fluorescent signal and large field of view via the acoustofluidic scanning fluorescence nanoscope provides a powerful tool for versatile nanoscale fluorescence imaging for researchers in the fields of medicine, biology, biophysics, and biomedical engineering.

Acoustofluidic Interfaces for the Mechanobiological Secretome of MSCs.

While mesenchymal stem cells (MSCs) have gained enormous attention due to their unique properties of self-renewal, colony formation, and differentiation potential, the MSC secretome has become attractive due to its roles in immunomodulation, anti-inflammatory activity, angiogenesis, and anti-apoptosis. However, the precise stimulation and efficient production of the MSC secretome for therapeutic applications are challenging problems to solve. Here, we report on Acoustofluidic Interfaces for the Mechanobiological Secretome of MSCs: AIMS. We create an acoustofluidic mechanobiological environment to form reproducible three-dimensional MSC aggregates, which produce the MSC secretome with high efficiency. We confirm the increased MSC secretome is due to improved cell-cell interactions using AIMS: the key mediator N-cadherin was up-regulated while functional blocking of N-cadherin resulted in no enhancement of the secretome. After being primed by IFN-γ, the secretome profile of the MSC aggregates contains more anti-inflammatory cytokines and can be used to inhibit the pro-inflammatory response of M1 phenotype macrophages, suppress T cell activation, and support B cell functions. As such, the MSC secretome can be modified for personalized secretome-based therapies. AIMS acts as a powerful tool for improving the MSC secretome and precisely tuning the secretory profile to develop new treatments in translational medicine.