Biology subjects

Balciunaite, A.

Publications and source records attributed to Balciunaite, A..

7 recordsLinked to original sources

bioRxiv2026

ABC transporters support Drosophila intestinal stem and progenitor cells during cytotoxic challenge

Adult stem cells can survive diverse insults, from ionizing radiation to toxic chemicals. In vertebrates, ABC transporter expression and dye-efflux capacity have been associated with stem-cell protection and multidrug resistance. How compound accumulation differs between adult stem cells and their differentiated daughters within an intact tissue remains poorly understood. Here, we show that adult Drosophila intestinal stem/progenitor cells maintain a distinct low-accumulation state for membrane-permeable compounds and that ABC transporters contribute to this phenotype and to the response to cytotoxic stress. Across nine membrane-permeable probes, stem/progenitor cells accumulated eight at lower levels than differentiated enterocytes. We selected tetramethylrhodamine methyl ester (TMRM), a membrane-permeable fluorescent probe that showed a strong difference in accumulation between stem/progenitor cells and enterocytes, as a quantitative readout for an RNAi screen of all 56 Drosophila ABC-family genes. The screen identified seven candidate transporters whose depletion increased the stem/progenitor-to-enterocyte TMRM fluorescence ratio. Further characterization of one of them, ABCB7, showed that ABCB7-depleted guts contained fewer mitotic cells during cytotoxic drug exposure. These results implicate ABC transporters in lower compound accumulation in Drosophila intestinal stem/progenitor cells and support a role for ABC transporters in their response to cytotoxic challenge.

genetics↗

bioRxiv2026

3D Human Neuromuscular Architecture Encoded by Compliant Patterned Hydrogel Scaffolds

Engineered human neuromuscular models are limited by a trade-off between biological fidelity and architectural control: self-assembled organoids organize stochastically, while engineered 3D tissues impose anisotropy through passive tension at the edges without internal guidance. Here we encode architectural guidance into human neuromuscular tissues by coupling a three-dimensional, cell-laden biomatrix to a xolographically printed hydrogel substrate featuring sub-millimeter surface topography. We demonstrate that grooved substrates increase human primary myotube alignment and maturation in the overlying 3D tissue, while guiding directional axon extension from human iPSC-derived motor neuron spheroids. We show that combining both cell types along a shared alignment axis establishes functional neuromuscular connectivity, evidenced by acetylcholine receptor clustering, glutamate-evoked contraction and its blockade by d-tubocurarine (curare), and yields innervation coverage of centimeter scale tissues. Overall, this platform combines compliant substrates, mesoscale tissue architectural guidance, and human-relevant cell biology in a single untethered construct for studies of neuromuscular tissue development and function.

bioengineering↗

bioRxiv2026

Cell-Dense Bioink Design for Xolography: Coupling Refractive Index-Matching with Increased Photoreactivity

Bioxolography enables high-resolution fabrication of geometrically complex, cell-laden constructs for tissue engineering. However, tissue-relevant cell densities conflict with the optical transparency required for efficient dual-color volumetric printing. In this work, we extend the Bioxolography toolbox to include refractive index (RI) matching for cell-laden bioresins using iodixanol (IDX). Remarkably, IDX enhances optical transparency and boosts reactivity -- a phenomenon unique to Xolography. Yet, excessive IDX compromises dual-color efficiency through increased absorption and undesired UV-only curing, underscoring a central trade-off between optical clarity and photochemical performance. Systematic tuning of resin compositions along an iso-refractive index line demonstrated the versatility of Bioxolography, with IDX enhancing polymerization and 4-Hydroxy-TEMPO providing biocompatible inhibition. Optimizing composition and printing parameters yielded GelMA hydrogels with cell densities up to 5{middle dot}106 cells{middle dot}mL-1. Cell-laden prints achieved sub-100 {micro}m resolution and complex geometries such as channels and gyroids. Using skeletal muscle tissue as a model, we validated RI matched Bioxolography as a promising strategy for tissue engineering by demonstrating cell alignment along printed grooves and formation of mature muscle fibers characterized by MyoHC+ staining and fusion index. By integrating physical, chemical, and biological perspectives, this work advances Xolography toward biomaterials development and reinforces its position as an emerging volumetric (bio)printing technology. Table of Contents O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=175 SRC="FIGDIR/small/729865v1_ufig1.gif" ALT="Figure 1"> View larger version (86K): org.highwire.dtl.DTLVardef@19c0380org.highwire.dtl.DTLVardef@1a9e920org.highwire.dtl.DTLVardef@84210org.highwire.dtl.DTLVardef@294112_HPS_FORMAT_FIGEXP M_FIG C_FIG For printing higher cell density bioresins with Xolography, iodixanol (IDX) is added for refractive index-matching. The addition leads to an unexpected additional effect with increased reactivity in the dual-color photopolymerization. With careful adjustment of the resin composition and the printing parameters, Bioxolography is proven as a viable tool for tissue engineering.

bioengineering↗

bioRxiv2024

Bilayered Biofabrication Unlocks the Potential of Skeletal Muscle for Biohybrid Soft Robots

The emerging field of biohybrid robotics aims to create the next generation of soft and sustainable robots by using engineered biological muscle tissues integrated with soft materials as artificial muscles (bio-actuators). Both cardiac and skeletal muscle cells can be used for biohybrid actuation. Generally, cardiac bio-actuators take the shape of thin cellular films, while locomotive skeletal muscle bio-actuators form bulk tissues. The geometry of a bio-actuator should be optimized for the type of desired motion, e.g., thin film layers are optimal for swimming actuators mimicking fish. Until now, the geometry of skeletal muscle bio-actuators has been constrained to ring- or block-like tissues generally differentiated around a pair of pillars due to the need to oppose the contraction force exerted during the skeletal muscle differentiation process. In this work, we extend the possible geometry of skeletal muscle bio-actuators by demonstrating a bilayered design that mimics the motion of jellyfish. We take advantage of a volumetric printing method, i.e., xolography, which allows us to micropattern poly(ethylene glycol) diacrylate and gelatin methacrylate hydrogels to serve as scaffolds for seeding a layer of the skeletal muscle cell matrix. We demonstrate the locomotion speed of our bio-actuators is 3.4x faster than previously reported counterparts. In addition, our skeletal bio-actuators outperform most cardiac ones. Further optimization of our bilayer biofabrication for improved reproducibility of the maturation process of the skeletal muscle tissue will pave the way for the next generation of performant skeletal muscle-based actuators for biohybrid robots.

bioengineering↗

bioRxiv2024

Integrated Closed-loop Control of Bio-actuation for Proprioceptive Bio-hybrid Robots

Biohybrid robots are emergent soft robots that combine engineered artificial structures and living biosystems to exploit unique characteristics of biological cells and tissues. Skeletal muscle tissue-based bio-actuators can respond to externally applied stimuli, such as electrical fields. However, current bio-actuation systems rely on open-loop control strategies that lack knowledge of the actuators state. The regulation of output force and position of bio-hybrid robots requires self-sensing control systems that combine bio-actuators with sensors and control paradigms. Here, we propose a soft, fiber-shaped mechanical sensor based on a composite with piezoresistive properties that efficiently integrates with engineered skeletal muscle tissue and senses its contracting states in a cell culture environment in the presence of applied electrical fields. After testing the sensors insulation and biocompatibility, we characterized its sensitivity for typical strains (<1%) and proved its ability to detect motions from contractile skeletal muscle tissue constructs. Finally, we showed that the sensor response can feed an autonomous control system, thus demonstrating the first proprioceptive bio-hybrid robot that can sense and respond to its contraction state. In addition to inspiring intelligent implantable systems, informative biomedical models, and other bioelectronic systems, the proposed technology will encourage strategies to exceed the durability, design, and portability limitations of biohybrid robots and confer them decisional autonomy, thus driving the paradigm shift between bio-actuators and intelligent bio-hybrid robots. One Sentence SummaryIntegrating soft mechanical sensors into engineered skeletal muscle tissue enables bio-hybrid robots with proprioception.

bioengineering↗

bioRxiv2023

Perfusable biohybrid designs for bioprinted skeletal muscle tissue

Engineered, centimeter-scale skeletal muscle tissue (SMT) can mimic muscle pathophysiology to study development, disease, regeneration, drug response, and motion. Macroscale SMT requires perfusable channels to guarantee cell survival and support elements to enable mechanical cell stimulation and uniaxial myofiber formation. Here, stable biohybrid designs of centimeter-scale SMT are realized via extrusion-based bioprinting of an optimized polymeric blend based on gelatin methacryloyl and sodium alginate, which can be accurately co-printed with other inks. A perfusable microchannel network is designed to functionally integrate with perfusable anchors for insertion into a maturation culture template. The results demonstrate that (i) co-printed synthetic structures display highly coherent interfaces with the living tissue; (ii) perfusable designs preserve cells from hypoxia all over the scaffold volume; and (iii) constructs can undergo passive mechanical tension during matrix remodeling. Extrusion-based multimaterial bioprinting with our inks and design realizes in vitro matured biohybrid SMT for biomedical, nutritional, and robotic applications.

bioengineering↗

bioRxiv2019

ABC transporters confer multidrug resistance to Drosophila intestinal stem cells

Adult stem cells can survive a wide variety of insults from ionizing radiation to toxic chemicals1-3. To date, the multidrug resistant features of stem cells have been characterized only in vertebrates, where there is a critical need to understand how cancer stem cells thwart chemotherapy drugs4-6. These studies reveal that the ability of both normal and cancer stem cells to survive toxins hinges on their high levels of expression of ABC transporters, transmembrane pumps that efflux lipophilic compounds out of cells7,8. This has been observed across a wide spectrum of vertebrate stem cells including breast, blood, intestine, liver, and skin, suggesting that high efflux ability and multidrug resistance may be general features of stem cells that distinguish them from their differentiated daughter cells. Here we show that these previously described vertebrate stem cell features are conserved in Drosophila intestinal stem cells. Using a novel in vivo efflux assay and multiple drug challenges, we show that stem cells in the fly intestine depend on two ABC transporters--one constitutively expressed and the other induced--for efflux and multidrug resistance. These results suggest that stem cell multidrug resistance by ABC transporters is a general stem cell feature conserved over 500 million years of evolution.

cell biology↗