Biology subjects

Hibino, N.

Publications and source records attributed to Hibino, N..

6 recordsLinked to original sources

bioRxiv2026

Adaptive-like features of the γδ TCR couple chronic BTNL recognition to NK-like tissue immunity

Intestinal V{gamma}4 {gamma}{delta} intraepithelial lymphocytes (IELs) persistently bind the constitutively expressed epithelial ligand BTNL3/8 through germline-encoded T cell receptor (TCR) determinants. While they resemble innate-like T cells such as NKT cells, unlike these populations, V{gamma}4 IELs encounter ligand only after thymic development. Moreover, unlike conventional {beta} T cells, V{gamma}4 IELs sustain persistent physiological ligand engagement without becoming exhausted. Here, using biophysical, functional, and multimodal single-cell approaches, we show how V{gamma}4 IELs address this challenge. While germline-encoded TCR regions broadly mediate BTNL3 recognition, productive activation requires additional non-germline TCR features that license responsiveness to BTNL3/8 and enable local selection in the gut. Rather than driving exhaustion, BTNL3/8 reactivity directly promotes expression of an NK-like program marked by adaptor molecules that license innate-like signaling in healthy tissue. These findings reveal how combined innate and adaptive features of the {gamma}{delta}TCR enable durable tissue specialization under conditions of persistent physiological ligand engagement.

immunology↗

bioRxiv2026

In Vivo Bioincubation Promotes Maturation of Human iPSC-Derived Cardiomyocytes in Neonatal Rat and Pig Hearts

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) hold great promise for cardiac regenerative medicine and disease modeling. However, hiPSC-CMs generated through conventional in vitro differentiation exhibit immature, fetal-like phenotypes. While in vivo bioincubation in neonatal rodent hearts promotes hiPSC-CM maturation toward adult-like phenotypes, studies in large animal models remain limited, particularly with detailed morphological characterization. In this study, we investigated bioincubation of fluorescently labeled hiPSC-CMs in both neonatal rat and pig hearts. Human iPSCs were differentiated into cardiomyocytes expressing GFP or RFP reporters and subsequently injected intramyocardially into neonatal rats (GFP-labeled) and pigs (RFP-labeled). After 4-8 weeks of bioincubation, fluorescent hiPSC-CMs were isolated using large-particle fluorescence-activated cell sorting (COPAS), which preserves cellular morphology of adult-like cardiomyocytes. Immunostaining for cardiac troponin T revealed well-organized sarcomeric structures in multinucleated hiPSC-CMs. Bioincubated hiPSC-CMs displayed rod-shaped morphology with binucleation, characteristic features of mature adult cardiomyocytes. Quantitative analysis demonstrated that bioincubated hiPSC-CMs from rat hearts exhibited sarcomere length and cell circularity comparable to native rat adult cardiomyocytes, though with higher intra-cellular variability in sarcomere organization. Histological examination confirmed successful engraftment of RFP-positive hiPSC-CMs within pig myocardium, with engrafted cells also displaying mature adult-like features. These findings provide critical proof-of-concept data for bioincubation in large animal models and support further investigation for disease modeling, drug screening, and regenerative cell therapies. SIGNIFICANCE STATEMENTHuman induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) offer tremendous potential for cardiac disease modeling and regenerative therapies, but their clinical application is limited by their immature characteristics. Here we show that in vivo bioincubation in neonatal rat hearts enables hiPSC-CMs to achieve structural maturity, exhibiting features of adult cardiomyocytes, including organized sarcomeres, rod-shaped morphology, and multinucleation. We further provided proof-of-concept evidence for engraftment in neonatal pig hearts for maturation, supporting feasibility in large animal models. The use of large-particle cell sorting enables recovery of intact, adult-sized cardiomyocytes for subsequent analysis. These findings establish a practical and scalable platform for generating structurally mature human cardiomyocytes through in vivo bioincubation.

developmental biology↗

bioRxiv2025

Tissue Engineering Applications for Novel Integrated and Mobile Perfusion System

Perfusion offers unique benefits to tissue-engineered systems, enhancing oxygen and nutrient transport which improves tissue formation and growth. In this study, we present a novel and integrated portable perfusion system, termed the FluidON. Weighing <10 lbs, the system can maintain continuous flow in a standard incubation environment (37{degrees}C, 5% CO2), effectively functioning as a portable perfusion and culture chamber. To test the systems perfusion parameters, we measured the volumetric flow rate across a range of pressures and found that the system could achieve flow as low as 0.40{+/-} 0.19uL/s, which is similar to in vivo interstitial flow. Computational fluid dynamics revealed uniform flow distribution, laminar flow, and gentle circulation, helping ensure even fluid and nutrient distribution. To study the biocompatibility of the system, bioengineered tissue patches were created and perfused. Viability was assessed through flow cytometry. The system does not adversely affect cell health as the viability of perfused samples was found to be 40.99{+/-}6.22% alive after 24 hours (n=4), while that of the static control was 38.56{+/-}4.22% alive (n=4). To determine the effects of perfusion on spheroid spatial arrangement, perfused tissue patches were analyzed with light microscopy. It was discovered that perfusion promoted spheroid aggregation and cohesion, causing the distance from one spheroid to its nearest neighbor to decrease after 24 hours of perfusion. Perfusion was also found to improve the strength of hydrogels as the average hole area, caused by hydrolytic enzymes that degrade the hydrogel matrix, was smaller in perfused conditions compared to the control. Complemented by its ability to provide mobile perfusion and incubation, this novel integrated portable perfusion system holds promise for promoting tissue maturation, elevating tissue bioengineering studies.

bioengineering↗

bioRxiv2022

Perfusable Apparatus For Thick-tissue Creation And Growth (patch) Of Cardiac Tissue

Cardiac tissue engineering has been developed as a potential alternative treatment for heart failure. However, current 3D tissues are limited in size and thickness due to the lack of an effective vascularization method. We have developed a novel bioreactor system to create viable vascularized cardiac tissue from multicellular spheroids using a digital light processing (DLP) 3D bioprinting system. Spheroids were created from induced pluripotent stem cells (iPSC) and cardiac fibroblasts (FB) using special dimple plates for mass production. One centimeter cubic tissues were created from spheroids using a DLP 3D printed mold with vascular channels. The tissue was maintained in a perfusion chamber under regulated flow and pressure following differentiation to cardiac tissue and endothelialization. Mass production of large spheroids (35,000 / tissue, diameter of 395.99 um +/- 101.15 um) was achieved from 170 million iPSCs and 50 million FBs for the creation of 1cm3 cardiac tissue in a 3D printed mold with vascular channels. The cardiac tissues (n=5) were perfused for 20 days under stable pressure of 17.5 +/- 3.05 PSI and flow of 5000 uL/min +/- 1116.42 uL/min. On days 10 and 20, Alamar blue assays showed viability for all five tissues (Alamar blue intensity: Day 10 1.57 +/- 0.15. Day 20 2.21 +/- 0.19). Thick and viable cardiac tissues were created and maintained using a 3D printed vascularized mold and perfusion system for maturation and growth in vitro for 30 days. This technology will open new doors for viable in vitro cardiac tissue creation.

bioengineering↗

bioRxiv2021

Computational Fontan Analysis: Preserving accuracy while expediting workflow

BackgroundPost-operative outcomes of the Fontan operation have been linked to graft shape after implantation. Computational fluid dynamics (CFD) simulations are used to explore different surgical options. The objective of this study is to perform a systematic in vitro validation for investigating the accuracy and efficiency of CFD simulation to predict Fontan hemodynamics. MethodsCFD simulations were performed to measure indexed power loss (iPL) and hepatic flow distribution (HFD) in 10 patient-specific Fontan models, with varying mesh and numerical solvers. The results were compared with a novel in vitro flow loop setup with 3D printed Fontan models. A high-resolution differential pressure sensor was used to measure the pressure drop for validating iPL predictions. Microparticles with particle filtering system were used to measure HFD. The computational time was measured for a representative Fontan model with different mesh sizes and numerical solvers. ResultsWhen compared to in vitro setup, variations in CFD mesh sizes had significant effect on HFD (p = 0.0002) but no significant impact on iPL (p = 0.069). Numerical solvers had no significant impact in both iPL (p = 0.50) and HFD (P = 0.55). A transient solver with 0.5 mm mesh size requires computational time 100 times more than a steady solver with 2.5 mm mesh size to generate similar results. ConclusionsThe predictive value of CFD for Fontan planning can be validated against an in vitro flow loop. The prediction accuracy can be affected by the mesh size, model shape complexity and flow competition.

bioinformatics↗

bioRxiv2021

Noncanonical Notch signals have opposing roles during cardiac development

The Notch pathway is an ancient intercellular signaling system with crucial roles in numerous cell-fate decision processes across species. While the canonical pathway is activated by ligand-induced cleavage and nuclear localization of membrane-bound Notch, Notch can also exert its activity in a ligand/transcription-independent fashion, which is conserved in Drosophila, Xenopus, and mammals. However, the noncanonical role remains poorly understood in in vivo processes. Here we show that increased levels of the Notch intracellular domain (NICD) in the early mesoderm inhibit heart development, potentially through impaired induction of the second heart field (SHF), independently of the transcriptional effector RBP-J. Similarly, inhibiting Notch cleavage, shown to increase noncanonical Notch activity, suppressed SHF induction in embryonic stem cell (ESC)-derived mesodermal cells. In contrast, NICD overexpression in late cardiac progenitor cells lacking RBP-J resulted in an increase in heart size. Our study suggests that noncanonical Notch signaling has stagespecific roles during cardiac development.

developmental biology↗