Biology subjects

Bailey, S. J.

Publications and source records attributed to Bailey, S. J..

3 recordsLinked to original sources

bioRxiv2025

A Transient Immunostimulatory Niche Synergizes Adoptive and Endogenous Immunity for Enhanced Tumor Control

Adoptive Cell Therapy (ACT) has achieved curative responses in hematological malignancies, yet its translation to solid tumors remains limited by manufacturing bottlenecks, systemic toxicities, and poor T-cell infiltration and persistence within the immunosuppressive tumor microenvironment (TME). Here, we report the development and mechanism of ACTIVATE (Adoptive Cell Therapy and Immunostimulatory Vehicle for Anti-Tumor Efficacy), which leverages an injectable hydrogel depot technology that forms a transient inflammatory niche for localized co-delivery of adoptive T cells and native cytokines. By tuning cytokine identity, ACTIVATE enables precise modulation of T-cell expansion, effector function, and interaction with endogenous immune networks. We found that enhancing T-cell proliferation alone is insufficient to drive robust tumor control; instead, coordinated engagement of both adoptive and endogenous immune responses is critical for durable anti-tumor efficacy. In vivo, this orchestration via ACTIVATE led to enhanced infiltration and cytotoxicity of both adoptive and host-derived immune effectors, while driving robust recruitment and activation of T cells, B cells, dendritic cells, and macrophages in the tumor-draining lymph nodes. This local immune activation can further reshape the TME, promoting antigen presentation and suppressing immunoregulatory populations, thus enhancing anti-tumor efficacy in murine melanoma and lymphoma models. These findings establish ACTIVATE as a modular platform for orchestrating coordinated immune responses to improve ACT outcomes in solid tumors.

immunology↗

bioRxiv2025

Preventing peritendinous adhesions using lubricious supramolecular hydrogels

Of the 1.5 million emergency room visits each year in the United States due to flexor tendon injuries in the hand, over 30-40% result in peritendinous adhesions which can limit range of motion (ROM) and severely impact an individuals quality of life. Adhesions are fibrous scar-like tissues which can form between adjacent tissues in the body in response to injury, inflammation, or during normal healing following surgery. Currently, there is no widespread solution for adhesion prevention in the delicate space of the digit while allowing a patient full ROM quickly after surgery. There is a clear clinical need for a material capable of limiting adhesion formation which is simple to apply, does not impair healing, remains at the application site during motion and initial inflammation (days - weeks), and leaves tendon glide unencumbered. In this work, we developed dynamically crosslinked, bioresorbable supramolecular hydrogels as easy-to-apply lubricious barriers to prevent the formation of peritendinous adhesions. These hydrogels exhibit excellent long-term stability, injectability, and thermally stable viscoelastic properties that allow for simple storage and facile application. We evaluated interactions at the interface of the hydrogels and relevant tissues, including human tendon and skin, in shear and extensional stress modes and demonstrated a unique mechanism of adhesion prevention based on maintenance of a lubricious hydrogel barrier between tissues. Ex vivo studies show that the hydrogels did not impair the gliding behavior nor mechanical properties of tendons when applied in cadaveric human hands following clinically relevant flexor tendon repair. We further applied these hydrogels in a preclinical rat Achilles tendon injury model and observed prolonged local retention at the repair site as well as improved recovery of key functional metrics, including ROM and maximal dorsiflexion. Further, these hydrogels were safe and did not impair tendon strength nor healing compared to the current standard of care. These dynamic, biocompatible hydrogels present a novel solution to the significant problem of peritendinous adhesions with clear translational potential.

bioengineering↗

bioRxiv2024

A thiol--ene click-based strategy to customize injectable polymer--nanoparticle hydrogel properties for therapeutic delivery

Polymer-nanoparticle (PNP) hydrogels are a promising injectable biomaterial platform that has been used for a wide range of biomedical applications including adhesion prevention, adoptive cell delivery, and controlled drug release. By tuning the chemical, mechanical, and erosion properties of injected hydrogel depots, additional control over cell compatibility and pharmaceutical release kinetics may be realized. Here, we employ thiol-ene click chemistry to prepare a library of modified hydroxypropylmethylcellulose (HPMC) derivatives for subsequent use in PNP hydrogel applications. When combined with poly(ethylene glycol)-b-poly(lactic acid) nanoparticles, we demonstrate that systematically altering the hydrophobic, steric, or pi stacking character of HPMC modifications can readily tailor the mechanical properties of PNP hydrogels. Additionally, we highlight the compatibility of the synthetic platform for the incorporation of cysteine-bearing peptides to access PNP hydrogels with improved bioactivity. Finally, through leveraging the tunable physical properties afforded by this method, we show hydrogel retention time in vivo can be dramatically altered without sacrificing mesh size or cargo diffusion rates. This work offers a route to optimize PNP hydrogels for a variety of translational applications and holds promise in the highly tunable delivery of pharmaceuticals and adoptive cells.

bioengineering↗