Viability Of Spheroids Research Articles

Microfluidic device-assisted 3D cell spheroids isolation, staining and embedding

3D cell spheroids have emerged as indispensable tools in cell biology research. In this study, the efficacy of an open-close switchable microfluidic device for on-chip staining and agar-embedding of 3D spheroids was thoroughly validated, especially in preparation for immunohistochemistry (IHC) analysis. The on-chip staining procedure, employing Trypan blue and Calcein-AM/PI staining, was demonstrated to evaluate the cell viability of spheroids. During overextended culture periods, a discernible decline in cell viability was observed at the central region of the spheroids, offering valuable information on the temporal aspects of spheroid development. On-chip agar embedding stands out for its precise control over the location and orientation of three-dimensional spheroids, a key factor in exploring cellular architecture, especially in fused spheroids using IHC analysis. In comparison to tube-based staining, this method significantly cuts down on reagent use and analysis time. This not only boosts efficiency but also lowers the risk of spheroid damage or loss during staining, highlighting its potential for handling miniaturized tissue samples and biopsies in cell assays. The on-chip staining and agar-embedding techniques presented here not only provide valuable insights into spheroids’ behavior but also pave the way for further developments in miniaturized tissue analysis and cell-based assays.

Enhancing Bone Formation Through bFGF-Loaded Mesenchymal Stromal Cell Spheroids During Fracture Healing in Mice.

This study aimed to evaluate the osteogenic potential of mesenchymal stromal cell (MSC) spheroids combined with the basic fibroblast growth factor (bFGF) in a mouse femur fracture model. To begin, MSC spheroids were generated, and the expression of key trophic factors (bFGF Bmp2, and Vegfa) was assessed using quantitative PCR (qPCR). A binding assay confirmed the interaction between the bFGF and the spheroids' extracellular matrix. The spheroid cultures significantly upregulated bFGF, Bmp2, and Vegfa expression compared to the monolayers (p < 0.001), and the binding assay demonstrated effective bFGF binding to the MSC spheroids. Following these in vitro assessments, the mice were divided into five groups for the in vivo study: (1) no treatment (control), (2) spheroids alone, (3) bFGF alone, (4) bFGF-loaded spheroids (bFGF-spheroids), and (5) non-viable (frozen) bFGF-loaded spheroids (bFGF-dSpheroids). Bone formation was analyzed by a micro-CT, measuring the bone volume (BV) and bone mineral content (BMC) of the mice four weeks post-fracture. A high dose of the bFGF (10 µg) significantly promoted bone formation regardless of the presence of spheroids, as evidenced by the increases in BV (bFGF, p = 0.010; bFGF-spheroids, p = 0.006; bFGF-dSpheroids, p = 0.032) and BMC (bFGF, p = 0.023; bFGF-spheroids, p = 0.004; bFGF-dSpheroids, p = 0.014), compared to the controls. In contrast, a low dose of the bFGF (1 µg) combined with the MSC spheroids significantly increased BV and BMC compared to the control (BV, p = 0.012; BMC, p = 0.015), bFGF alone (BV, p = 0.012; BMC, p = 0.008), and spheroid (BV, p < 0.001; BMC, p < 0.001) groups. A low dose of the bFGF alone did not significantly promote bone formation (p > 0.05). The non-viable (frozen) spheroids loaded with a low dose of the bFGF resulted in a higher BV and BMC compared to the spheroids alone (BV, p = 0.003; BMC, p = 0.017), though the effect was less pronounced than in the viable spheroids. These findings demonstrate the synergistic effect of the bFGF and MSC spheroids on bone regeneration. The increased expression of the BMP-2 and VEGF observed in the initial experiments, coupled with the enhanced bone formation in vivo, highlight the therapeutic potential of this combination. Future studies will aim to elucidate the underlying molecular mechanisms and assess the long-term outcomes for bone repair strategies.

Impact of Polydeoxyribonucleotides on the Morphology, Viability, and Osteogenic Differentiation of Gingiva-Derived Stem Cell Spheroids

Background and Objectives: Polydeoxyribonucleotides (PDRN), composed of DNA fragments derived from salmon DNA, is widely recognized for its regenerative properties. It has been extensively used in medical applications, such as dermatology and wound healing, due to its ability to enhance cellular metabolic activity, stimulate angiogenesis, and promote tissue regeneration. In the field of dentistry, PDRN has shown potential in promoting periodontal healing and bone regeneration. This study aims to investigate the effects of PDRN on the morphology, survival, and osteogenic differentiation of gingiva-derived stem cell spheroids, with a focus on its potential applications in tissue engineering and regenerative dentistry. Materials and Methods: Gingiva-derived mesenchymal stem cells were cultured and formed into spheroids using microwells. The cells were treated with varying concentrations of PDRN (0, 25, 50, 75, and 100 μg/mL) and cultivated in osteogenic media. Cell morphology was observed over seven days using an inverted microscope, and viability was assessed with Live/Dead Kit assays and Cell Counting Kit-8. Osteogenic differentiation was evaluated by measuring alkaline phosphatase activity and calcium deposition. The expression levels of osteogenic markers RUNX2 and COL1A1 were quantified using real-time polymerase chain reaction. RNA sequencing was performed to assess the gene expression profiles related to osteogenesis. Results: The results demonstrated that PDRN treatment had no significant effect on spheroid diameter or cellular viability during the observation period. However, a PDRN concentration of 75 μg/mL significantly enhanced calcium deposition by Day 14, suggesting increased mineralization. RUNX2 and COL1A1 mRNA expression levels varied with PDRN concentration, with the highest RUNX2 expression observed at 25 μg/mL and the highest COL1A1 expression at 75 μg/mL. RNA sequencing further confirmed the upregulation of genes involved in osteogenic differentiation, with enhanced expression of RUNX2 and COL1A1 in PDRN-treated gingiva-derived stem cell spheroids. Conclusions: In summary, PDRN did not significantly affect the viability or morphology of gingiva-derived stem cell spheroids but influenced their osteogenic differentiation and mineralization in a concentration-dependent manner. These findings suggest that PDRN may play a role in promoting osteogenic processes in tissue engineering and regenerative dentistry applications, with specific effects observed at different concentrations.

Harnessing Nitric Oxide-Donating Benzofuroxans for Targeted Inhibition of Carbonic Anhydrase IX in Cancer.

We describe here the design and antitumor evaluation of benzofuroxan-based nitric oxide (NO)-donor hybrid derivatives targeting human carbonic anhydrases (hCAs) IX and XII. The most effective compounds, 27 and 28, demonstrated potent dual action, exhibiting low nanomolar inhibition constants against hCA IX and significant NO release. Notably, compound 27 showed significant antiproliferative effects against various cancer cell lines, particularly renal carcinoma A-498 cells. In these cells, it significantly reduced the expression of CA IX and iron-regulatory proteins, inducing apoptosis via mitochondrial caspase activity and ferroptosis pathways, as evidenced by increases in ROS, nitrite, and down-regulated expression of ferritin-encoding genes. In three-dimensional tumor models, compound 27 effectively reduced spheroid size and viability. In vivo toxicity studies in mice indicated that the compounds were well-tolerated, with no significant alterations in kidney function. These findings underscore the potential of benzofuroxan-based CA inhibitors for further preclinical evaluations as therapeutic agents targeting renal cell carcinoma.

Biofabrication of prevascularized spheroids for bone tissue engineering by fusion of microvascular fragments with osteoblasts.

Spheroids are promising building blocks for scaffold-free bone tissue engineering. Their rapid vascularization is of major importance to guarantee their survival after transplantation. To achieve this, we herein introduce the biofabrication of prevascularized spheroids by fusion of adipose tissue-derived microvascular fragments (MVF) with osteoblasts (OB). For this purpose, 200 MVF from donor mice and 5,000, 10,000 or 20,000 murine OB (MC3T3-E1) were co-cultured in a liquid overlay system for 3days to generate OB + MVF spheroids. OB mono-culture spheroids served as controls. During the generation process, the diameters of all spheroids progressively decreased, resulting in compact, viable spheroids of homogeneous sizes. MVF promoted the maturation of spheroids containing 5,000 OB, as shown by an accelerated decline of cell proliferation due to contact inhibition. Moreover, MVF most effectively reassembled into new microvascular networks within these small spheroids when compared to the other spheroid types, indicating the most beneficial MVF to OB ratio. Accordingly, these spheroids also showed a high angiogenic sprouting activity in vitro. In contrast to OB spheroids, they further rapidly vascularized in vivo after transplantation into dorsal skinfold chambers. This was caused by the interconnection of incorporated MVF with surrounding blood vessels. These findings indicate that OB + MVF spheroids may be suitable for bone tissue engineering, which should be next tested in appropriate in vivo bone defect models.

Doxorubicin-loaded liposome-like particles embedded in chitosan/hyaluronic acid-based hydrogels as a controlled drug release model for local treatment of glioblastoma

Glioblastoma (GBM) resection and medication treatment are limited, and local drug therapies are required. This study aims to create a hybrid system comprising liposome-like particles (LLP-DOX) encapsulated in chitosan/hyaluronic acid/polyethyleneimine (CHI/HA/PEI) hydrogels, enabling controlled local delivery of doxorubicin (DOX) into the resection cavity for treating GBM. CHI/HA/PEI hydrogels were characterized morphologically, physically, chemically, mechanically, and thermally. Findings revealed a high network and compact micro-network structure, along with enhanced physical and thermal stability compared to CHI/HA hydrogels. Simultaneously, drug release from CHI/HA/PEI/LLP-DOX hydrogels was assessed, revealing continuous and controlled release up to the 148th hour, with no significant burst release. Cell studies showed that CHI/HA/PEI hydrogels are biocompatible with low genotoxicity. Additionally, LLP-DOX-loaded CHI/HA/PEI hydrogels significantly decreased cell viability and gene expression levels compared to LLP-DOX alone. It was also observed that the viability of GBM spheroids decreased over time when interacting with CHI/HA/PEI/LLP-DOX hydrogels, accompanied by a reduction in total surface area and an increase in apoptotic tendencies. In this study, we hypothesized that creating a hybrid drug delivery system by encapsulating DOX-loaded LLPs within a CHI/HA/PEI hydrogel matrix could achieve sustained drug release, improve anticancer efficacy via localized treatment, and effectively mitigate GBM progression for 3D microtissues.

Automated Uniform Spheroid Generation Platform for High Throughput Drug Screening Process.

Three-dimensional (3D) spheroid models are crucial for cancer research, offering more accurate insights into tumour biology and drug responses than traditional 2D cell cultures. However, inconsistent and low-throughput spheroid production has hindered their application in drug screening. Here, we present an automated high-throughput platform for a spheroid selection, fabrication, and sorting system (SFSS) to produce uniform gelatine-encapsulated spheroids (GESs) with high efficiency. SFSS integrates advanced imaging, analysis, photo-triggered fabrication, and microfluidic sorting to precisely control spheroid size, shape, and viability. Our data demonstrate that our SFSS can produce over 50 GESs with consistent size and circularity in 30 min with over 97% sorting accuracy while maintaining cell viability and structural integrity. We demonstrated that the GESs can be used for drug screening and potentially for various assays. Thus, the SFSS could significantly enhance the efficiency of generating uniform spheroids, facilitating their application in drug development to investigate complex biological systems and drug responses in a more physiologically relevant context.

Formation of cell spheroids using Standing Surface Acoustic Wave (SSAW).

3D bioprinting becomes one of the popular approaches in the tissue engineering. In this emerging application, bioink is crucial for fabrication and functionality of constructed tissue. The use of cell spheroids as bioink can enhance the cell-cell interaction and subsequently the growth and differentiation of cells in the 3D printed construct with the minimum amount of other biomaterials. However, the conventional methods of preparing the cell spheroids have several limitations, such as long culture time, low-throughput, and medium modification. In this study, the formation of cell spheroids by SSAW was evaluated both numerically and experimentally in order to overcome the aforementioned limitations. The effects of excitation frequencies on the cell accumulation time, diameter of the formed cell spheroids, and subsequently, the growth and viability of cell spheroids in the culture medium over time were studied. Using the high-frequency (23.8 MHz) excitation, cell accumulation time to the pressure nodes could be reduced in comparison to that of the low-frequency (10.4 MHz) excitation, but in a smaller spheroid size. SSAW excitation at both frequencies does not affect the cell viability up to 7 days, > 90% with no statistical difference compared with the control group. In summary, SSAW can effectively prepare the cell spheroids as bioink for the future 3D bioprinting and various biotechnology applications (e.g., pharmaceutical drug screening and tissue engineering).

Chemotherapeutic Potential of Chlorambucil-Platinum(IV) Prodrugs against Cisplatin-Resistant Colorectal Cancer Cells.

Chlorambucil-platinum(IV) prodrugs exhibit multi-mechanistic chemotherapeutic activity with promising anticancer potential. The platinum(II) precursors of the prodrugs have been previously found to induce changes in the microtubule cytoskeleton, specifically actin and tubulin of HT29 colon cells, while chlorambucil alkylates the DNA. These prodrugs demonstrate significant anticancer activity in 2D cell and 3D spheroid viability assays. A notable production of reactive oxygen species has been observed in HT29 cells 72 h post treatment with prodrugs of this type, while the mitochondrial membrane potential was substantially reduced. The cellular uptake of the chlorambucil-platinum(IV) prodrugs, assessed by ICP-MS, confirmed that active transport was the primary uptake mechanism, with platinum localisation identified primarily in the cytoskeletal fraction. Apoptosis and necrosis were observed at 72 h of treatment as demonstrated by Annexin V-FITC/PI assay using flow cytometry. Immunofluorescence measured via confocal microscopy showed significant changes in actin and tubulin intensity and in architecture. Western blot analysis of intrinsic and extrinsic pathway apoptotic markers, microtubule cytoskeleton markers, cell proliferation markers, as well as autophagy markers were studied post 72 h of treatment. The proteomic profile was also studied with a total of 1859 HT29 proteins quantified by mass spectroscopy, with several dysregulated proteins. Network analysis revealed dysregulation in transcription, MAPK markers, microtubule-associated proteins and mitochondrial transport dysfunction. This study confirms that chlorambucil-platinum(IV) prodrugs are candidates with promising anticancer potential that act as multi-mechanistic chemotherapeutics.

Proanthocyanidin surface preconditioning of dental pulp stem cell spheroids enhances dimensional stability and biomineralization invitro.

Lack of adequate mechanical strength and progressive shrinkage over time remain challenges in scaffold-free microtissue-based dental pulp regeneration. Surface collagen cross-linking holds the promise to enhance the mechanical stability of microtissue constructs and trigger biological regulations. In this study, we proposed a novel strategy for surface preconditioning microtissues using a natural collagen cross-linker, proanthocyanidin (PA). We evaluated its effects on cell viability, tissue integrity, and biomineralization of dental pulp stem cell (DPSCs)-derived 3D cell spheroids. Microtissue and macrotissue spheroids were fabricated from DPSCs and incubated with PA solution for surface collagen cross-linking. Microtissue viability was examined by live/dead staining and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, with transverse dimension change monitored. Microtissue surface stiffness was measured by an atomic force microscope (AFM). PA-preconditioned microtissues and macrotissues were cultured under basal or osteogenic conditions. Immunofluorescence staining of PA-preconditioned microtissues was performed to detect dentin sialophosphoprotein (DSPP) and F-actin expressions. PA-preconditioned macrotissues were subjected to histological analysis, including haematoxylin-eosin (HE), alizarin red, and Masson trichrome staining. Immunohistochemistry staining was used to detect alkaline phosphatase (ALP) and dentin matrix acidic phosphoprotein 1 (DMP-1) expressions. PA preconditioning had no adverse effects on microtissue spheroid viability and increased surface stiffness. It reduced dimensional shrinkage for over 7 days in microtissues and induced a larger transverse-section area in the macrotissue. PA preconditioning enhanced collagen formation, mineralized nodule formation, and elevated ALP and DMP-1 expressions in macrotissues. Additionally, PA preconditioning induced higher F-actin and DSPP expression in microtissues, while inhibition of F-actin activity by cytochalasin B attenuated PA-induced dimensional change and DSPP upregulation. PA surface preconditioning of DPSCs spheroids demonstrates excellent biocompatibility while effectively enhancing tissue structure stability and promoting biomineralization. This strategy strengthens tissue integrity in DPSC-derived spheroids and amplifies osteogenic differentiation potential, advancing scaffold-free tissue engineering applications in regenerative dentistry.

Polo-like kinase 1 inhibition modulates urinary tract smooth muscle contraction and bladder cell transcriptional programs.

The serine/threonine kinase polo-like kinase 1 (PLK1) is a master regulator of cell proliferation and contraction, but its physiological role in the lower urinary tract is unknown. We utilized transcriptomic programs of human bladder smooth muscle cells (hBSMCs), 3D bladder spheroid viability assays, and human ureterovesical junction contractility measurements to elucidate the impacts of PLK1 inhibition. This work reveals PLK1 reduction with the selective inhibitor TAK-960 (500 nM) suppresses high K+-evoked contractions of human urinary smooth muscle ex vivo while decreasing urothelial cell viability. Transcriptomic analysis of hBSMCs treated with TAK-960 shows modulation of cell cycle and contraction pathways, specifically through altered expression of Cys2/His2-type zinc finger transcription factors. In bladder spheroids, PLK1 inhibition also suppresses smooth muscle contraction protein filamin. Taken together, these findings establish PLK1 is a critical governor of urinary smooth muscle contraction and urothelial proliferation with implications for lower urinary tract disorders. Targeting PLK1 pharmacologically may therefore offer therapeutic potential to ameliorate hypercontractility and aberrant growth. Further elucidation of PLK1 signaling networks promises new insights into pathogenesis and much needed treatment advances for debilitating urinary symptoms.

Pantoprazole and riluzole target H+/K+-ATPases and pH-sensitive K+ channels in pancreatic cancer cells.

Pancreatic ductal adenocarcinoma (PDAC) remains the most lethal cancer type. PDAC is characterized by fibrotic, hypoxic, and presumably acidic tumor microenvironment (TME). Acidic TME is an important player in tumor development, progression, aggressiveness, and chemoresistance. The dysregulation of ductal ion transporters/channels might contribute to extracellular pH (pHe) acidification and PDAC progression. Our aim was to test whether H+/K+-ATPases and pH-sensitive K+ channels contribute to these processes and could be targeted by clinically approved drugs. We used human pancreatic cancer cells adapted to various pHe conditions and grown in monolayers and spheroids. First, we created cells expressing pHoran4 at the outer plasma membrane and showed that pantoprazole, the H+/K+-ATPase inhibitor, alkalinized pHe. Second, we used FluoVolt to monitor the membrane voltage (Vm) and showed that riluzole hyperpolarized Vm, most likely by opening of pH-sensitive K+ channels such as TREK-1. Third, we show that pantoprazole and riluzole inhibited cell proliferation and viability of monolayers and spheroids of cancer cells adapted to various pHe conditions. Most importantly, combination of the two drugs had significantly larger inhibitory effects on PDAC cell survival. We propose that co-targeting H+/K+-ATPases and pH-sensitive K+ channels by re-purposing of pantoprazole and riluzole could provide novel acidosis-targeted therapies of PDAC.

Influence of storage conditions on the viability of spheroids from human chondrocytes

BACKGROUND: The use of tissue-engineered products for treating hyaline cartilage injuries is currently a promising direction for regenerative medicine. The study of storage and transportation conditions of such preparations is essential in product development because it determines the viability and functional activity of the cellular component of the product. In addition, such work should be performed following the requirements of Russian legislation before using the developed drug product in clinical trials. AIM: To characterize the storage conditions for tissue-engineered preparations such as chondrospheres. METHODS: Chondrospheres were formed from human chondrocytes obtained from the biopsy material of the knee joint cartilage of patients diagnosed according to ICD-10 codes M15–M19. After the formation of chondrospheres, cell viability was examined using the metabolic dye PrestoBlue, and the expression of chondrogenic markers (SOX9, aggrecan, collagen type 1 and type 2) was preserved using real-time polymerase chain reaction under various transportation conditions, i.e., at different storage times, medium composition, and temperature. RESULTS: The analysis of the expression of chondrocyte markers confirmed that cells in chondrospheres retain a chondrocyte phenotype. In the cell viability study of tissue-engineered products under various conditions (temperature, solution, and time), the most favorable environment for storing the product was phosphate buffer saline and 0.9% sodium chloride solution (р 0.05). The metabolic activity of the cells that make up the tissue-engineered product was maintained when stored at +4 °C for up to 3 days (р 0.05). CONCLUSION: Isotonic solution and temperature regime +4 °C for not more than 2 days showed the preferable medium and conditions for storing and transporting the prototype cartilage implant as chondrospheres.

Immune Cell-Based Microrobots for Remote Magnetic Actuation, Antitumor Activity, and Medical Imaging.

Translating medical microrobots into clinics requires tracking, localization, and performing assigned medical tasks at target locations, which can only happen when appropriate design, actuation mechanisms, and medical imaging systems are integrated into a single microrobot. Despite this, these parameters are not fully considered when designing macrophage-based microrobots. This study presents living macrophage-based microrobots that combine macrophages with magnetic Janus particles coated with FePt nanofilm for magnetic steering and medical imaging and bacterial lipopolysaccharides for stimulating macrophages in a tumor-killing state. The macrophage-based microrobots combine wireless magnetic actuation, tracking with medical imaging techniques, and antitumor abilities. These microrobots are imaged under magnetic resonance imaging and optoacoustic imaging in soft-tissue-mimicking phantoms and ex vivo conditions. Magnetic actuation and real-time imaging of microrobots are demonstrated under static and physiologically relevant flow conditions using optoacoustic imaging. Further, macrophage-based microrobots are magnetically steered toward urinary bladder tumor spheroids and imaged with a handheld optoacoustic device, where the microrobots significantly reduce the viability of tumor spheroids. The proposed approach demonstrates the proof-of-concept feasibility of integrating macrophage-based microrobots into clinic imaging modalities for cancer targeting and intervention, and can also be implemented for various other medical applications.

CREB5 as an essential transcription and tumorigenic regulator in basal-like breast and prostate cancer.

1107 Background: Breast cancers (BC) harbor basal-like transcriptional profiles, in which a large subset are pathologically triple negative breast cancers (TNBC). These are hormone therapy insensitive, have limited targeted therapies, and decreased overall survival (OS). Recent studies determined that prostate cancers (PCs) also exhibit luminal- or basal-like transcriptional subtypes. The 30-40% of basal-like PCs exhibit resistance to hormone therapies and have overall worse clinical outcomes. Here we deployed in silico computational models and tumor phenotype testing in vitro and in vivo. This identified that CREB5, a transcription factor commonly amplified or overexpressed in advanced cancers, regulates basal-like BCs and PCs through stem cell-like genes and properties that drive tumor formation. Methods: Protein and RNA levels were examined in 5 subtypes of BC from the TCGA (n=981). Normalized expression and PAM50 signatures were analyzed using data from Decipher tests of PC patients (n=585). Kaplan-Meier curves were used to compare relapse free survival in PC (n=84) and OS in TNBC (n=248). The ALAN (Algorithm for Linking Activity Networks (1) computational tool was used to determine gene-gene similarities of ~20,000 genes based on ~400,000,000 pairwise comparisons in 208 tumors. In PC (LNCaP) and TNBC (MDA-MB-231 and HCC1806) cell lines, we examined gene expression profiles from RNA-seq and found Hallmark signatures through Gene Set Enrichment Analysis. Motif analysis was conducted from ChIP-seq data on immuno-precipitated CREB5. We conducted in vitro and in vivo assessment of tumorigenicity. Results: Basal BCs harbored increased CREB5 expression and CREB5-high basal BCs had worse outcomes (HR 2.09, 95% CI 1.1-3.96, p&lt;0.021). Reflecting this, in basal-like BC cell lines, CREB5 increased cell viability and formation of tumor-like spheroids in 3D culture. In PCs, CREB5 had a positive correlation with basal- and not luminal-like PCs (Spearman ρ = 0.519, p&lt;0.001). Through ALAN analysis of metastatic PCs, CREB5 exhibited strong concordance with other known resistance genes (FGFR1/2) as well as transcription factors that promote stem cell-like features. Particularly, CREB5 was associated with increased FOSL1 (Spearman ρ = 0.37, p&lt;0.001), a metastasis-regulating gene. In PC cell lines, CREB5 overexpression promoted FOSL1 and other stem cell-like genes and co-bound to FOSL1 transcription regulatory elements. CREB5 overexpression in PC cell lines promoted the formation of tumor-like colonies, spheroids, and increased tumor formation from the xenografts in mice. Conclusions: Basal-like BCs and PCs demonstrate overexpression of CREB5, a gene that promotes tumor formation and stem cell-like genes. This mechanistic knowledge may guide treatment management strategies and aid in the development of novel therapies against basal-like BCs and PCs. 1. Bergom et al, Communications Biology, 2023.

Assessment of the biological activity of Marrubium friwaldskyanum Boiss. (Lamiaceae)

Present scientific evidences about the biological activity and potential medical application of extracts derived from Marrubium friwaldskyanum Boiss. are limited. Therefore, our study was undertaken to define several main characteristics in this regard – in vitro cytotoxicity and antitumor properties, antibacterial activity and immunomodulatory potential. Extracts were obtained from different aerial parts of Marrubium friwaldskyanum – stems, leaves and flowers. The in vitro cytotoxicity and antitumor activity of the samples were evaluated by tetrazolium salt reduction tests and Neutral red uptake assays using four human cell lines (a normal fibroblastic and three adenocarcinoma cell lines/A549, HeLa, HT-29/) and by experiments with HT-29 tumor spheroids. Antibacterial activity toward Gram-negative (Escherichia coli) and Gram-positive (Bacillus cereus) species was assessed based on estimation of minimal inhibitory and minimal bactericidal concentrations as well as longitudinal studies on bacterial viability. Ex vivo assays with normal leukocytes were performed to define potential immunomodulatory activity of the extracts. Our results demonstrated selective antitumor activity of the extracts directed against colon adenocarcinoma HT-29 cells and cervical adenocarcinoma HeLa cell line. Metabolic activity of A549 lung adenocarcinoma cells was affected only by the sample derived from flowers. M. friwaldskyanum leaf and flower extracts showed the highest activity, which included reduction of HT-29 tumor spheroid growth and viability. The studied samples exhibited antibacterial activity against both bacterial species tested. Treatment with M. friwaldskyanum extracts affected specific leukocyte populations (HLA+, CD19+, CD11b+, CD25+ cells). These results demonstrate for the first time complex biological effects of extracts derived from M. friwaldskyanum and their potential to serve as a source of valuable compounds for the pharmaceutical industry.

Selecting serum-free hepatocyte cryopreservation stage and storage temperature for the application of an “off-the-shelf” bioartificial liver system

The bioartificial liver (BAL) system can potentially rescue acute liver failure (ALF) patients by providing partial liver function until a suitable donor liver can be found or the native liver has self-regenerated. In this study, we established a suitable cryopreservation process for the development of an off-the-shelf BAL system. The viability of hepatocyte spheroids cryopreserved in liquid nitrogen was comparable to that of fresh primary hepatocyte spheroids. When hepatocyte spheroids were subjected to cryopreservation in a deep freezer, no statistically significant differences were observed in ammonia removal rate or urea secretion rate based on the cryopreservation period. However, the functional activity of the liver post-cryopreservation in a deep freezer was significantly lower than that observed following liquid nitrogen cryopreservation. Moreover, cryopreserving spheroid hydrogel beads in a deep freezer resulted in a significant decrease (approximately 30%) in both ammonia removal and urea secretion rates compared to the group cryopreserved in liquid nitrogen. The viabilities of spheroid hydrogel beads filled into the bioreactor of a BAL system were similar across all four groups. However, upon operating the BAL system for 24 h, the liver function activity was significantly higher in the group comprising hydrogel beads generated after thawing hepatocyte spheroids cryopreserved in liquid nitrogen. Consequently, the manufacturing of beads after the cryopreservation of hepatocyte spheroids is deemed the most suitable method, considering efficiency, economic feasibility, and liver function activity, for producing a BAL system.

Highly variable biological effects of statins on cancer, non-cancer, and stem cells in vitro

Statins, the drugs used for the treatment of hypercholesterolemia, have come into the spotlight not only as chemoadjuvants, but also as potential stem cell modulators in the context of regenerative therapy. In our study, we compared the in vitro effects of all clinically used statins on the viability of human pancreatic cancer (MiaPaCa-2) cells, non-cancerous human embryonic kidney (HEK 293) cells and adipose-derived mesenchymal stem cells (ADMSC). Additionally, the effect of statins on viability of MiaPaCa-2 and ADMSC cells spheroids was tested. Furthermore, we performed a microarray analysis on ADMSCs treated with individual statins (12 μM) and compared the importance of the effects of statins on gene expression between stem cells and pancreatic cancer cells. Concentrations of statins that significantly affected cancer cells viability (< 40 μM) did not affect stem cells viability after 24 h. Moreover, statins that didn´t affect viability of cancer cells grown in a monolayer, induce the disintegration of cancer cell spheroids. The effect of statins on gene expression was significantly less pronounced in stem cells compared to pancreatic cancer cells. In conclusion, the low efficacy of statins on non-tumor and stem cells at concentrations sufficient for cancer cells growth inhibition, support their applicability in chemoadjuvant tumor therapy.

In Situ Self-Assembling Liver Spheroids with Synthetic Nanoscaffolds for Preclinical Drug Screening Applications.

Drug-induced liver injury (DILI) is one of the most common reasons for acute liver failure and a major reason for the withdrawal of medications from the market. There is a growing need for advanced in vitro liver models that can effectively recapitulate hepatic function, offering a robust platform for preclinical drug screening applications. Here, we explore the potential of self-assembling liver spheroids in the presence of electrospun and cryomilled poly(caprolactone) (PCL) nanoscaffolds for use as a new preclinical drug screening tool. This study investigated the extent to which nanoscaffold concentration may have on spheroid size and viability and liver-specific biofunctionality. The efficacy of our model was further validated using a comprehensive dose-dependent acetaminophen toxicity protocol. Our findings show the strong potential of PCL-based nanoscaffolds to facilitate in situ self-assembly of liver spheroids with sizes under 350 μm. The presence of the PCL-based nanoscaffolds (0.005 and 0.01% w/v) improved spheroid viability and the secretion of critical liver-specific biomarkers, namely, albumin and urea. Liver spheroids with nanoscaffolds showed improved drug-metabolizing enzyme activity and greater sensitivity to acetaminophen compared to two-dimensional monolayer cultures and scaffold-free liver spheroids. These promising findings highlight the potential of our nanoscaffold-based liver spheroids as an in vitro liver model for drug-induced hepatotoxicity and drug screening.

Activity of hydrogel-vitamin D3 /bacterioruberin nanoparticles on imiquimod-induced fibroblasts-keratinocytes spheroids

Topical administration of vitamin D3 (VD3) analogs and corticosteroids is the mainstay treatment for mild localized psoriasis. VD3 however is an unstable class II drug (insoluble and permeable), classically formulated as unattractive viscous and oil-based ointments or creams. In this work, nanostructured archaeolipid carriers (NAC) with a core loaded with VD3 and the C50 dipolar carotenoid from halophilic archaea bacterioruberin (BR): NAC-VD3, were formulated into a carbopol hydrogel: gNAC-VD3. After its rheological characterization, its anti-inflammatory and antioxidant activity was assessed on bi-cellular spheroids, consisting of a core of fibroblasts surrounded by a ring of keratinocytes activated with imiquimod (IMQ) as a psoriasis model. gNAC-VD3 (0.8 mg VD3/135 μg BR/gram gel) conserved the antioxidant activity, showed pseudoplastic non-Newtonian behaviour, stability over time, good occlusion capacity and spreadability, all suitable properties for topical application in patients with psoriasis. gNAC-VD3 did not decrease the viability of spheroids but significantly reduced the release of proinflammatory cytokines (IL-8, IL-6, TNF-α), oxidative stress (ROS), and matrix metalloproteinases from IMQ-induced spheroids to levels similar to the uninduced spheroids. Results suggest that gNAC-VD3 may constitute a potential anti-inflammatory agent for the topical treatment of mild psoriasis and deserves further in vivo exploration.