Biology subjects

Uto, K.

Publications and source records attributed to Uto, K..

4 recordsLinked to original sources

bioRxiv2026

Immunomodulatory mechanisms of submicron phosphatidylserine-exposing polymeric particles (PSPs)

Macrophages are highly dynamic cells that maintain tissue homeostasis by regulating both initiation and resolution of inflammation. During efferocytosis, macrophages recognize the eat me signal, phosphatidylserine (PS), exposed at the surface of apoptotic cells, leading to the resolution of inflammation and acquisition of a pro-resolving phenotype. Inspired by this endogenous mechanism, PS-based biomaterials have demonstrated immunomodulatory potential. However, the molecular mechanisms underlying PS-mediated macrophage reprogramming remain poorly understood. Here, submicron PS-exposing polymeric particles (PSPs; [~]300 nm) were developed to improve the suitability of PSP formulations for future systemic administration while preserving their immunomodulatory activity. PSPs were efficiently internalized by macrophages through both actin- and dynamin-dependent pathways. PSP treatment significantly reduced IL-6 and IL-12p70 production in LPS-stimulated macrophages, whereas induction of the classical anti-inflammatory M2 marker CD206 was limited. Transcriptomic analysis revealed coordinated attenuation of inflammatory signaling pathways, including downregulation of Myd88, Nfkb1, Rel, and Irf8, together with activation of NRF2-associated antioxidant pathways characterized by increased expression of Nfe2l2, Hmox1, Prdx1, Gclm, and Gclc. Activation of antioxidant-associated genes together with reduced Irf8 expression suggests that PSP promotes inflammatory resolution through coordinated redox adaptation and selective attenuation of inflammatory signaling. Collectively, these findings provide mechanistic insight into PS-mediated macrophage reprogramming and support the future development of systemically administered therapies for chronic inflammatory diseases, including vascular inflammatory disorders. HighlightsO_LISubmicron PSPs retain immunomodulatory activity of apoptotic cell-mimicking biomaterials. C_LIO_LIPSPs are rapidly internalized through actin- and dynamin-dependent pathways. C_LIO_LIPSPs attenuate inflammatory signaling and selectively suppress IL-6 and IL-12p70 production. C_LIO_LIPSPs induce NRF2-associated antioxidant and glutathione responses. C_LIO_LITranscriptomics reveals an early redox-adaptive macrophage program. C_LI

bioengineering↗

bioRxiv2025

Dual inhibition of glutaminolysis and autophagy suppresses proliferation of Rheumatoid arthritis fibroblast-like synoviocytes and mitigates arthritis in SKG mice

Recent evidence highlights the critical role of immune metabolism in the pathogenesis of rheumatoid arthritis (RA). We previously demonstrated that glutaminase 1 (GLS1), a key enzyme in glutamine metabolism, is upregulated in fibroblast-like synoviocytes from RA patients (RA-FLS) and that GLS1 inhibition exerts an antiproliferative effect on RA-FLS. Glutaminolysis has also been shown to suppress autophagy, raising the possibilitiy that inhibiting glutaminolysis may enhance autophagy. Given this interplay, we hypothesized that dual inhibition of glutaminolysis and autophagy could synergistically suppress RA-FLS proliferation. This study aimed to investigate the effects of combining autophagy and glutaminolysis inhibition on RA-FLS and arthritis in SKG mice. We utilized chloroquine (CQ) as an autophagy inhibitor and compound 968 (C968), a GLS1 inhibitor, to suppress glutaminolysis. Treatment with C968 upregulated LC3B and ATG5 expression and increased LC3-II protein levels in RA-FLS, indicative of enhanced autophagy. Furthermore, C968 promoted autophagosome formation in RA-FLS. These findings confirm that glutaminolysis inhibition enhances autophagy in RA-FLS. The combination of C968 and CQ significantly inhibited RA-FLS proliferation and increased apoptotic cell death. Moreover, C968-CQ co-treatment markedly alleviated arthritis severity in SKG mice. Our findings suggest that concurrent suppression of glutaminolysis and autophagy represents a promising therapeutic strategy for RA.

immunology↗

bioRxiv2025

Visualizing the Chronicle of Multiple Cell Fate using a Near-IR Dual-RNA/DNA-Targeting Probe

Early detection and late-stage cell fate assessment are key factors to develop therapeutic strategies, although current methods cannot capture early responses or distinguish multiple injury states, especially in UV-vis-sensitive cells. Here, we introduce a method to simultaneously detect variations in RNA and DNA under near-infrared photoexcitation. Utilizing a pyrazinacene-based probe (TEG8-N14), we unexpectedly achieved discrimination of multiple cell states, including apoptosis, necrosis, necroptosis, and senescence, based on RNA-DNA changes. Specifically, TEG8-N14 selectively stains necrotic cells in live samples, while after fixation, it allows detection of ultra-early senescence in UV-vis-sensitive cells, providing approximately two-fold greater informational content than existing RNA or DNA fluorophores. These findings break current imaging barriers by enabling comprehensive visualization of single-cell fate histories without being affected by UV-vis or genetic manipulation.

bioengineering↗

bioRxiv2023

Injectable microcapillary network hydrogels engineered by liquid-liquid phase separation for stem cell transplantation

Injectable hydrogels are promising carriers for cell delivery in regenerative medicine. However, injectable hydrogels composed of crosslinked polymer networks are often non porous and prevent biological communication with host tissues through signals, nutrients, oxygen, and cells, thereby limiting graft survival and tissue integration. Here we report injectable hydrogels with liquid-liquid phase separation-induced microcapillary networks ({micro}CN) as stem cell-delivering scaffolds. The molecular modification of gelatin with hydrogen bonding moieties induced liquid-liquid phase separation when mixed with unmodified gelatin to form {micro}CN structures in the hydrogels. Through spatiotemporally controlled covalent crosslinking and dissolution processes, porous {micro}CN structures were formed in the hydrogels, which can enhance mass transport and cellular activity. The encapsulation of cells with injectable {micro}CN hydrogels improved cellular adhesion, spreading, migration, and proliferation. Transplantation of mesenchymal stem cells with injectable {micro}CN hydrogels enhanced graft survival and recovered hindlimb ischemia by enhancing material-tissue communication with biological signals and cells through {micro}CN. This facile approach may serve as an advanced scaffold for improving stem cell transplantation therapies in regenerative medicine.

bioengineering↗