Improving outcomes for high-risk acute lymphoblastic leukaemia (ALL) patients requires increasingly personalized treatment strategies that leverage molecular and omics-based assays as well as functional screens. However, to date, only a few of these approaches are clinically actionable and easily adopted in clinical settings. To that end, we report a combination drug screening assay (GradientScreen) that correlates with clinical outcomes using standard paediatric ALL treatment protocols. This assay uses a microfluidic device to generate overlapping drug gradients and implements an analysis framework that characterizes drug synergy and efficacy in a ratiometric manner. Using partial least squares regression, we show that our combination response metrics correlate with both minimal residual disease (MRD) following initiation of treatment and later clinical end-points. Here, we further demonstrate that this system could be used to evaluate response to experimental therapeutic regimens in patients who did not respond to standard treatment. This assay can serve as a research-enabling tool for the field, with potential to integrate into clinical pathology workflows to identify difficult-to-treat ALL patients and screen for alternative treatment strategies at diagnosis. A gradient-based microfluidic framework analyses the functional responses of leukaemia cells from paediatric ALL patients to ratiometric combinations of three candidate drugs.
Current vaccine adjuvants, such as aluminum salts and emulsions, are limited by weak induction of cytotoxic T cell immunity and restricted ability to promote T helper type 1 responses, highlighting the need for safer and more effective alternatives. Here we show that microparticles generated from erythrocytes by controlled ultraviolet irradiation function as potent T helper type 1-skewing adjuvants that enhance tumour antigen-specific cytotoxic T cell responses in vitro and in multiple mouse tumour models. Following uptake by dendritic cells, these microparticles traffic to lysosomes and deliver haem cargo that is subsequently transported to the nucleus. Mechanistically, the particles elevate lysosomal pH, promoting lysosome movement towards the nucleus and enabling haem transfer, where haem activates REV-ERB⍺ and forms a co-repressor complex that suppresses peroxisome proliferator-activated receptor gamma, thereby relieving inhibition of dendritic cell maturation and antigen presentation. In vaccination settings, combining tumour antigens with erythrocyte-derived microparticles enhances cytotoxic T cell activation and suppresses tumour growth with minimal toxicity. These findings establish host-derived vesicles as a promising platform for next-generation cancer vaccine adjuvants. Microparticles generated from erythrocytes by controlled ultraviolet irradiation act as T helper type 1-skewing adjuvants that enhance tumour antigen-specific cytotoxic T cell responses in vitro and across mouse tumour models.
Local activation of regulatory T (Treg) cells represents a promising strategy for wound repair and tissue regeneration. However, current Treg-based therapies rely on adoptive cell transfer, which requires ex vivo expansion and reinfusion, posing challenges to donor variability and tissue specificity. Here we engineer a hydrogel-based system for in situ Treg activation at injury sites through the controlled release of AS2863619 (AS), a cyclin-dependent kinase inhibitor. AS is incorporated into collagen hydrogels at concentrations exceeding its solubility limit, reducing burst release and extending the release half-life. This continuous exposure to Treg-inducing agents stabilizes Foxp3 expression in CD4+ T cells, thereby enabling Treg induction and stabilization. The incorporation of laponite nanoparticles further slows AS release and prolongs drug retention. In a calvarial bone-defect model, AS-loaded hydrogels induce dose-dependent Treg cell activation, reduce pro-inflammatory macrophage responses and enhance bone regeneration. Notably, AS–laponite hydrogels achieve complete defect bridging in some cases. By providing spatiotemporal control over Treg populations without the need for cell isolation and expansion, this approach offers a scalable alternative for immunomodulation and tissue repair. A laponite nanoparticles-based hydrogel loaded with a cyclin-dependent kinase inhibitor induces localized regulatory T (Treg) cell activation directly in vivo and enhances bone regeneration in a calvarial bone-defect mouse model.
Microparticles released from ultraviolet-irradiated erythrocytes enhance anti-tumoural T cell immunity.
