Mechanical phenotyping of K562 cells by the Micropipette Aspiration Technique allows identifying mechanical changes induced by drugs

Atomic Force Microscopy for the Study of Cell Mechanics in Pharmaceutics

Cell mechanics is gaining attraction in drug screening, but the applicable methods have not yet become part of the standardized norm. This review presents the current state of the art for atomic force microscopy, which is the most widely available method. The field is first motivated as a new way of tracking pharmaceutical effects, followed by a basic introduction targeted at pharmacists on how to measure cellular stiffness. The review then moves on to the current state of the knowledge in terms of experimental results and supplementary methods such as fluorescence microscopy that can give relevant additional information. Finally, rheological approaches as well as the theoretical interpretations are presented before ending on additional methods and outlooks.

The role of chamomile oil against ochratoxin A in quail breeders: productive and reproductive performances, egg quality, and blood metabolites

This study aimed to evaluate the beneficial role of chamomile essential oil in improving productive and reproductive performances, egg quality, and blood metabolites and reducing the toxic effect of Ochratoxin A (OTA) in quail breeder's diets. A total of 144 mature quails, 8 wk old, were divided into 6 groups. The treatments were: G1 (the control), G2 (supplemented with OTA 1 mg/kg diet), G3 (supplemented with chamomile oil 0.5 g/kg diet), G4 (supplemented with chamomile oil 1 G/kg diet), G5 (supplemented with OTA 1 mg/kg diet + chamomile oil 0.5 g/kg diet), and G6 (supplemented with OTA 1 mg/kg diet + chamomile oil 1 g/kg diet). The OTA administration alone significantly decreased egg production and mass in quail breeders (P < 0.0001). Moreover, poor feed conversion ratio (FCR), fertility percentage (P < 0.0001), and hatchability percentage (P < 0.0009) were recorded. A significant decline (P < 0.05) in the levels of serum protein (total protein and globulin) was also recorded in OTA-contaminated groups, along with elevated serum levels of liver enzymes such as alanine transaminase (ALT) and Aspartate transaminase (AST) and kidney function test as urea and creatinine levels (P < 0.05). Ochratoxin A-contaminated feed resulted in a significant elevation (P < 0.05) in total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and very low-density lipoprotein (VLDL), along with a significant reduction (P < 0.05) in antioxidant status and immunological response. The supplementation of chamomile essential oil, either 0.5 g/kg or 1g/kg, to the basal diet or OTA-supplemented feed, revealed a significant increase in hatchability %, fertility, egg mass, and egg production and better FCR, egg quality, and immunological status when compared to OTA only. Moreover, chamomile essential oil supplementation improves liver and kidney function markers, decreases LDL, VLDL), TG, and TC. Along with a significant increase (P < 0.05) in terms of antioxidant status as glutathione peroxidase enzyme (GPX), total antioxidant capacity (TAC), and superoxide dismutase (SOD) and significantly (P < 0.05) improves immunological response as IgM, IgG, lysozyme and complement 3. In summary, chamomile oil supplementation, either separate or combined with OTA, reduced the adverse effects of OTA and led to improved productive and reproductive performance, egg quality, and blood metabolites in Japanese quail breeders.

Ameliorative effects of Dunaliella salina microalgae on nanoparticle (ZnO NPs)-induced toxicity in fish

Dunaliella salina (D. salina) is a well-known microalga that contains considerable amounts of nutritious and medicinal bioactive components. This work studied the modulatory role of D. salina against zinc oxide nanoparticle (ZnO NPs)-induced neurotoxic effects in adult zebrafish. Fishes were subjected to 0.69 mg L-1 (1/5th 96-h LC50) for 4 weeks; then, fishes were supplemented with D. salina in the diet for 2 weeks at two levels (15 and 30%). Exposure to ZnO NPs induced a significant increase in the levels of reactive oxygen species (ROS), hydrogen peroxide (H2O2), malondialdehyde (MDA), and 8-hydroxy-2-deoxyguanosine (8-OH-dG) while accompanied with downregulation of antioxidant genes in the brain of exposed fishes. Brain neurochemistry and enzyme activities were also altered following ZnO NP exposure. ZnO NPs significantly reduced the neurotransmitters and acetylcholinesterase (AchE) activity while increasing Alzheimer's disease-related proteins and inflammatory response via upregulation of tumor necrosis factor (TNF-α). Additionally, ZnO NPs increased the indices of brain's DNA oxidative damage, increasing brain tissue's metallothionein (MT) and zinc residues. ZnO NPs upregulated the transcription patterns of apoptosis-related genes (casp3 and p53). D. salina dietary co-supplementation with ZnO NPs alleviated the ZnO NPsZnO NP-induced neuro-oxidative damages by lowering the lipid, DNA damage, and inflammatory biomarkers. Besides, D. salina alleviating responses were linked with increasing the levels of the assessed antioxidants. Conclusively, D. salina dietary supplementation induced potential alleviating effects of the ZnO NP-induced neurotoxicity in adult zebrafish.

Phytosterol: nutritional significance, health benefits, and its uses in poultry and livestock nutrition

Medicinal plants with active ingredients have shown great potential as natural and sustainable additives in livestock and poultry diets as growth promoters, performance, feed conversion ratio, digestibility of nutrient enhancers, and antioxidants and immune system modulators. Among active ingredients, phytosterols, which are plant-based bio-factors that may be found in seeds, fruits, grains, vegetables and legumes, are thought to be involved in the aforementioned activities but are also widely known in human medicine due to their efficacy in treating diabetes, coronary heart disease, and tumors. Nevertheless, phytosterols can also promote carcinogens production, angiogenesis inhibition, metastasis, infiltration, and cancer cells proliferation. This review focuses on the deepening of the biological role and health benefits of phytosterols and their new potential application in poultry and livestock nutrition.

Extender Supplementation with Glutathione (GSH) and Taurine Improves In Vitro Sperm Quality and Antioxidant Status of New Zealand Rabbits during Chilled Storage for up to 72 hours

This study assessed the influence of supplementing the rabbit semen extender with various concentrations of glutathione (GSH) and taurine at 24, 48, and 72 h postchilling at 5°C. Semen samples were collected from 20 New Zealand bucks, and ejaculates with standard color, motility (>85%), about 0.5 mL volume, and ∼400 × 106/mL concentration were used and diluted with extenders supplemented with 0.5, 1, and 2 mM of GSH and 1, 5, and 10 mM of taurine and chilled at 5°C. Nonsupplemented samples were used as a control. Sperm's progressive motility, acrosome reaction, and extracellular oxidative stress biomarkers such as MDA contents and GPx, SOD, and CAT concentrations and intracellular transcriptomic levels of SOD and CAT genes were assessed. GSH and taurine supplementation improved the sperm's kinetics by reducing cooling-associated stress, which was ascertained by lowering MDA concentration and increasing SOD, CAT, and GPx concentrations (P < 0.05). Increasing the levels of antioxidant enzymes in the extender was due to the increasing mRNA copies of the SOD and CAT genes (P < 0.05). Furthermore, GSH and taurine maintained the fructose levels in the extender and lowered the GPT levels, which implies sperm membrane stability is maintained through GSH and taurine supplementation. GSH and taurine supplementation to the extender had protective influences on the in vitro rabbit semen quality during chilled storage for up to 72 h, which were remarkable with increasing supplementation dose and cooling time at 5°C.

Zinc Oxide Nanoparticles (ZnO-NPs) Induce Cytotoxicity in the Zebrafish Olfactory Organs via Activating Oxidative Stress and Apoptosis at the Ultrastructure and Genetic Levels

Nanotechnology has gained tremendous attention because of its crucial characteristics and wide biomedical applications. Although zinc oxide nanoparticles (ZnO-NPs) are involved in many industrial applications, researchers pay more attention to their toxic effects on living organisms. Since the olfactory epithelium is exposed to the external environment, it is considered the first organ affected by ZnO-NPs. Herein, we demonstrated the cytotoxic effect of ZnO-NPs on the olfactory organ of adult zebrafish after 60 days post-treatment. We opted for this period when fishes stop eating their diet from the aquarium, appear feeble, and cannot swim freely. Our study demonstrated that ZnO-NPs induced significant malformations of the olfactory rosettes at histological, ultrastructural, and genetic levels. At the ultrastructure level, the olfactory lamellae appeared collapsed, malformed, and twisted with signs of degeneration and loss of intercellular connections. In addition, ZnO-NPs harmed sensory receptor and ciliated cells, microvilli, rodlet, crypt, and Kappe cells, with hyper-activity of mucous secretion from goblet cells. At the genetic level, ZnO-NPs could activate the reactive oxygen species (ROS) synthesis expected by the down-regulation of mRNA expression for the antioxidant-related genes and up-regulation of DNA damage, cell growth arrest, and apoptosis. Interestingly, ZnO-NPs affected the odor sensation at 60 days post-treatment (60-dpt) more than at 30-dpt, severely damaging the olfactory epithelium and irreparably affecting the cellular repairing mechanisms. This induced a dramatically adverse effect on the cellular endoplasmic reticulum (ER), revealed by higher CHOP protein expression, that suppresses the antioxidant effect of Nrf2 and is followed by the induction of apoptosis via the up-regulation of Bax expression and down-regulation of Bcl-2 protein.

Automatic elasticity measurement of single cells using a microfluidic system with real-time image processing

The mechanical properties of cells are closely related to their physiological states and functions. Due to the limitations of conventional cell elasticity measurement technologies such as low throughput, cell-invasiveness, and high cost, microfluidic systems are emerging as powerful tools for high-throughput cell mechanical property studies. This paper introduces a microfluidic system to automatically measure the elastic modulus of single cells in real time. The system integrated a microfluidic chip with a microchannel for cell constriction, a pressure pump, a precision differential pressure sensor, and a program for online analysis of cell deformation. The program used a fast U-net to segment cell images and measure protrusion length during cell deformation. Subsequently, the cell elasticity was determined in real-time based on the deformation and required pressure using the power law rheological model. Finally, Young's modulus of BMSCs, Huh-7 cells, EMSCs, and K562 cells was measured as 25.13 ± 15.19 Pa, 69.74 ± 92.01 Pa, 54.50 ± 59.31 Pa and 58.43 ± 27.27 Pa, respectively. The microfluidic system has significant application potential in the automated evaluation of cell mechanical properties.Clinical Relevance-The technique in this paper may be used for the automatic and high throughput study of the stiffness of cells, such as stem cells and cancer cells. The stiffness data may contribute to stem cell therapy and cancer research.

Effect of Quercetin Nanoparticles on Hepatic and Intestinal Enzymes and Stress-Related Genes in Nile Tilapia Fish Exposed to Silver Nanoparticles

Recently, nanotechnology has become an important research field involved in the improvement of animals’ productivity, including aquaculture. In this field, silver nanoparticles (AgNPs) have gained interest as antibacterial, antiviral, and antifungal agents. On the other hand, their extensive use in other fields increased natural water pollution causing hazardous effects on aquatic organisms. Quercetin is a natural polyphenolic compound of many plants and vegetables, and it acts as a potent antioxidant and therapeutic agent in biological systems. The current study investigated the potential mitigative effect of quercetin nanoparticles (QNPs) against AgNPs-induced toxicity in Nile tilapia via investigating liver function markers, hepatic antioxidant status, apoptosis, and bioaccumulation of silver residues in hepatic tissue in addition to the whole-body chemical composition, hormonal assay, intestinal enzymes activity, and gut microbiota. Fish were grouped into: control fish, fish exposed to 1.98 mg L−1 AgNPs, fish that received 400 mg L−1 QNPs, and fish that received QNPs and AgNPs at the same concentrations. All groups were exposed for 60 days. The moisture and ash contents of the AgNP group were significantly higher than those of the other groups. In contrast, the crude lipid and protein decreased in the whole body. AgNPs significantly increased serum levels of ALT, AST, total cholesterol, and triglycerides and decreased glycogen and growth hormone (*** p < 0.001). The liver and intestinal enzymes’ activities were significantly inhibited (*** p < 0.001), while the oxidative damage liver enzymes, intestinal bacterial and Aeromonas counts, and Ag residues in the liver were significantly increased (*** p < 0.001, and * p < 0.05). AgNPs also significantly upregulated the expression of hepatic Hsp70, caspase3, and p53 genes (* p < 0.05). These findings indicate the oxidative and hepatotoxic effects of AgNPs. QNPs enhanced and restored physiological parameters and health status under normal conditions and after exposure to AgNPs.

Origanum vulgare Essential Oil Modulates the AFB1-Induced Oxidative Damages, Nephropathy, and Altered Inflammatory Responses in Growing Rabbits

The current study was performed to investigate the toxic effects of aflatoxin B1 (AFB1) through the evaluation of kidney function tests and histopathological examination of renal tissues, targeting the therapeutic role of Marjoram (Origanum vulgare essential oil-OEO) in improving health status. Forty-eight New Zealand Whites growing rabbits (four weeks old) weighing on average 660.5 ± 2.33 g were randomly and equally distributed into four groups, each of which had four replicas of three animals as the following: Control group (only basal diet), AFB1 group (0.3 mg AFB1/kg diet), OEO group (1 g OEO/kg diet) and co-exposed group (1 g OEO/kg + 0.3 mg AF/kg diet). Our study lasted eight weeks and was completed at 12 weeks of age. The results revealed that OEO decreased the toxic effects of AFB1 in rabbit kidneys by substantially reducing the cystatin C levels in the AFB1 group. Additionally, OEO decreased oxidative stress and lipid peroxidation levels in the co-exposed group. Moreover, OEO reduced DNA damage and inflammatory response in addition to the down-regulation of stress and inflammatory cytokines-encoding genes. Besides, OEO preserved the cytoarchitecture of rabbits' kidneys treated with AFB1. In conclusion, O. vulgare essential oil supplementation ameliorated the deleterious effects of AFB1 on the rabbits' kidneys by raising antioxidant levels, decreasing inflammation, and reversing oxidative DNA damage.

Quantifying Deformation and Migration Properties of U87 Glioma Cells Using Dielectrophoretic Forces

Glioblastoma multiforme is one of the most aggressive malignant primary brain tumors. To design effective treatment strategies, we need to better understand the behavior of glioma cells while maintaining their genetic and phenotypic stability. Here, we investigated the deformation and migration profile of U87 Glioma cells under the influence of dielectrophoretic forces. We fabricated a gold microelectrode array within a microfluidic channel and applied sinusoidal wave AC potential at 3 V_pp, ranging from 30 kHz to 10 MHz frequencies, to generate DEP forces. We followed the dielectrophoretic movement and deformation changes of 100 glioma cells at each frequency. We observed that the mean dielectrophoretic displacements of glioma cells were significantly different at varying frequencies with the maximum and minimum traveling distances of 13.22 µm and 1.37 µm, respectively. The dielectrophoretic deformation indexes of U87 glioma cells altered between 0.027-0.040. It was 0.036 in the absence of dielectrophoretic forces. This approach presents a rapid, robust, and sensitive characterization method for quantifying membrane deformation of glioma cells to determine the state of the cells or efficacy of administrated drugs.

Characterization and Antibacterial Evaluation of Biodegradable Mannose-Conjugated Fe-MIL-88NH2 Composites Containing Vancomycin against Methicillin-Resistant Staphylococcus aureus Strains

The emergence of bacterial resistance has increased the economic burden of infectious diseases dramatically during the previous few decades. Multidrug resistance (MDR) is difficult to cure in both Gram-negative and positive bacteria and is often incurable with traditional and broad-range antibiotics. Therefore, developing techniques to increase the antibacterial activity of therapeutic drugs is essential. Metal-organic frameworks (MOFs) are extremely versatile hybrid materials made of metal ions coupled via organic bridging ligands. They have been widely used as an excellent vehicle for drug delivery due to their low toxicity, biodegradability, and structural stability upon loading and functionalization. The present study focused on the synthesis of mannose (MNS)-coated MOFs with enhanced surface contact with S. aureus cells. The MNS coating on the surface of MOFs enhances their adherence to bacteria by binding to lectins present on the bacterial cell, resulting in improved VCM cellular penetration and activity against resistant bacteria. Various techniques, including atomic force microscopy, DLS, TGA, FT-IR, and DSC, were employed to analyze MNS-coated MOFs. They were also evaluated for their efficacy against resistant S. aureus. The results indicated that when VCM was loaded into MNS-coated MOFs, their bactericidal activity rose dramatically, resulting in the greater suppression of resistant S. aureus. AFM investigation of S. aureus strains demonstrated total morphological distortion after treatment with MNS-coated drug-loaded MOFs. The results of this work suggest that MNS-coated MOFs may be effective for reversing bacterial resistance to VCM and open new pathways for improving antibiotic therapy for diseases associated with MDR.

Chemical characterization of non-psychoactive Cannabis sativa L. extracts, in vitro antiproliferative activity and induction of apoptosis in chronic myelogenous leukaemia cancer cells

In this study, extracts from non‐psychoactive Cannabis sativa L. varieties were characterized by means of ultra high‐performance liquid chromatography coupled with high‐resolution mass spectrometry (UHPLC‐HRMS) and their antiproliferative activity was assessed in vitro. The human chronic myelogenous leukaemia cell line K562 was chosen to investigate the mechanism of cell death. The effect on the cell cycle and cell death was analysed by flow cytometry. Proteins related to apoptosis were studied by western blotting. Mechanical properties of cells were assessed using the Micropipette Aspiration Technique (MAT). The results indicated that the cannabidiol (CBD)‐rich extract inhibited cell proliferation of K562 cell line in a dose‐dependent manner and induced apoptosis via caspase 3 and 7 activation. A significant decrease in the mitochondrial membrane potential was detected, together with the release of cytochrome c into the cytosol. The main apoptotic markers were not involved in the mechanism of cell death. The extract was also able to modify the mechanical properties of cells. Thus, this hemp extract and its pure component CBD deserve further investigation for a possible application against myeloproliferative diseases, also in association with other anticancer drugs.

Dielectrophoretic characterization of dendritic cell deformability upon maturation

We have developed a rapid technique for characterizing the biomechanical properties of dendritic cells using dielectrophoretic forces. It is widely recognized that maturing of dendritic cells modulates their stiffness and migration capabilities, which results in T-cell activation triggering the adaptive immune response. Therefore it is important to develop techniques for mechanophenotyping of immature and mature dendritic cells. The technique reported here utilizes nonuniform electric fields to exert a substantial force on the cells to induce cellular elongation for optical measurements. In addition, a large array of interdigitated electrodes allows multiple cells to be stretched simultaneously. Our results indicate a direct correlation between F-actin activity and deformability observed in dendritic cells, determined through mean fluorescence signal intensity of phalloidin.

Cell elasticity measurement using a microfluidic device with real-time pressure feedback

The study of cell elasticity provides new insights into not only cell biology but also disease diagnosis based on cell mechanical state variation. Microfluidic technologies have made noticeable progress in studying cell deformation with capabilities of high throughput and automation. This paper reports the development of a novel microfluidic system to precisely measure the elasticity of cells having large deformation in a constriction channel. It integrated i) a separation unit to isolate rod- or flake-shaped particles that might block the constriction channel to increase the measurement throughput and ii) a pressure feedback system precisely detecting the pressure drop inducing the deformation of each cell. The fluid dynamics of the separation unit was modeled to understand the separation mechanism before the experimental determination of separation efficiency. Afterward, the pressure system was characterized to demonstrate its sensitivity and reproducibility in measuring the subtle pressure drop along a constriction channel. Finally, the microfluidic system was employed to study the stiffness of both K562 and endothelial cells. The cell protrusion and pressure drop were employed to calculate the mechanical properties based on a power-law rheology model describing the viscoelastic behaviors of cells. Both the stiffness and the fluidity of K562 and endothelial cells were consistent with those in previous studies. The system has remarkable application potential in the precise evaluation of cell mechanical properties.

Effect of Chicken Bone Extracts on Metabolic and Mitochondrial Functions of K562 Cell Line

Background: Tetracyclines’ use in intensive animal farming has raised some concerns regarding the biosafety for humans. Increasing evidences have revealed the presence of these drugs in processed animal by-products, such as bone, throughout the food chain. A potential off-target of tetracyclines is the bacterial-like mitochondrial translational machinery, thereby causing proteostatic alterations in mitochondrial DNA-encoded components of the oxidative phosphorylation system. Methods: The Seahorse methodology, confocal microscopy imaging of mitochondrial potential and reactive oxygen species, and q-RT-PCR analysis of the expression of genes involved in mitochondrial biogenesis and mitophagy were carried out on human lymphoblast derived K562 cell line challenged with bone powder derived from chicken treated with or without oxytetracycline and pure oxytetracycline. Results: A complex dose-dependent profile was attained with a low dosage of bone powder extracts causing a metabolic adaptation hallmarked by stimulation of the mitochondrial respiration and enhanced expression of mitochondriogenic factors in particular in cells challenged with oxytetracycline-free bone extract. Conversely, a higher dosage of bone powder extracts, regardless of their source, caused a progressive inhibition of mitochondrial respiration and glycolysis, ultimately leading to cell death. No significant effects of the pure oxytetracycline were observed. Conclusion: Bone powder, regardless of chicken treatment, contains and releases factors/chemicals responsible for the observed effects on energy metabolism. Quantitative differential effects appear to depend on biochemical alterations in the bone matrix caused by antibiotics rather than antibiotics themselves.

On-chip surface acoustic wave and micropipette aspiration techniques to assess cell elastic properties

The cytoskeletal mechanics and cell mechanical properties play an important role in cellular behaviors. In this study, in order to provide comprehensive insights into the relationship between different cytoskeletal components and cellular elastic moduli, we built a phase-modulated surface acoustic wave microfluidic device to measure cellular compressibility and a microfluidic micropipette-aspiration device to measure cellular Young's modulus. The microfluidic devices were validated based on experimental data and computational simulations. The contributions of structural cytoskeletal actin filament and microtubule to cellular compressibility and Young's modulus were examined in MCF-7 cells. The compressibility of MCF-7 cells was increased after microtubule disruption, whereas actin disruption had no effect. In contrast, Young's modulus of MCF-7 cells was reduced after actin disruption but unaffected by microtubule disruption. The actin filaments and microtubules were stained to confirm the structural alteration in cytoskeleton. Our findings suggest the dissimilarity in the structural roles of actin filaments and microtubules in terms of cellular compressibility and Young's modulus. Based on the differences in location and structure, actin filaments mainly contribute to tensile Young's modulus and microtubules mainly contribute to compressibility. In addition, different responses to cytoskeletal alterations between acoustophoresis and micropipette aspiration demonstrated that micropipette aspiration was better at detecting the change from actin cortex, while the response to acoustophoresis was governed by microtubule networks.

Stress hormone signaling through β-adrenergic receptors regulates macrophage mechanotype and function

Critical functions of immune cells require them to rapidly change their shape and generate forces in response to cues from their surrounding environment. However, little is known about how soluble factors that may be present in the microenvironment modulate key aspects of cellular mechanobiology-such as immune cell deformability and force generation-to impact functions such as phagocytosis and migration. Here we show that signaling by soluble stress hormones through β-adrenoceptors (β-AR) reduces the deformability of macrophages; this is dependent on changes in the organization of the actin cytoskeleton and is associated with functional changes in phagocytosis and migration. Pharmacologic interventions reveal that the impact of β-AR signaling on macrophage deformability is dependent on actin-related proteins 2/3, indicating that stress hormone signaling through β-AR shifts actin organization to favor branched structures rather than linear unbranched actin filaments. These findings show that through remodeling of the actin cytoskeleton, β-AR-mediated stress hormone signaling modulates macrophage mechanotype to impact functions that play a critical role in immune response.-Kim, T.-H., Ly, C., Christodoulides, A., Nowell, C. J., Gunning, P. W., Sloan, E. K., Rowat, A. C. Stress hormone signaling through β-adrenergic receptors regulates macrophage mechanotype and function.

Hypospermia Improvement in Dogs Fed on a Nutraceutical Diet

Male dog infertility may represent a serious concern in the canine breeding market. The aim of this clinical evaluation was to test the efficacy of a commercially available nutraceutical diet, enriched with Lepidium meyenii, Tribulus terrestris, L-carnitine, zinc, omega-3 (N-3) fatty acids, beta-carotene, vitamin E, and folic acid, in 28 male dogs suffering from infertility associated with hypospermia. All dogs received the diet over a period of 100 days. At the end of the evaluation period, no adverse effects, including head and tail anomalies percentage onset, were reported. Interestingly, motility percentage, semen volume and concentration, and total number of sperms per ejaculation significantly increased. Further investigations on a wider cohort of dogs might be useful to better correlate the presence of oxytetracycline in pet's diet and the onset of infertility and clearly assess the action mechanism of an oxytetracycline-free nutraceutical diet.

Characterizing Deformability of Drug Resistant Patient-Derived Acute Lymphoblastic Leukemia (ALL) Cells Using Acoustic Tweezers

The role of cell mechanics in cancer cells is a novel research area that has resulted in the identification of new mechanisms of therapy resistance. Single beam acoustic (SBA) tweezers are a promising technology for the quantification of the mechanical phenotype of cells. Our previous study showed that SBA tweezers can be used to quantify the deformability of adherent breast cancer cell lines. The physical properties of patient-derived (primary) pre-B acute lymphoblastic leukemia (ALL) cells involved in chemotherapeutic resistance have not been widely investigated. Here, we demonstrate the feasibility of analyzing primary pre-B ALL cells from four cases using SBA tweezers. ALL cells showed increased deformability with increasing acoustic pressure of the SBA tweezers. Moreover, ALL cells that are resistant to chemotherapeutic drugs were more deformable than were untreated ALL cells. We demonstrated that SBA tweezers can quantify the deformability of nonadherent leukemia cells and discriminate this mechanical phenotype in chemotherapy-resistant leukemia cells in a contact- and label-free manner.