Venous malformations (VMs) are caused by activation of the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mechanistic target of rapamycin (mTOR) and Abelson murine leukemia viral oncogene homolog 1 (c-ABL) pathways. Daily oral administration of rapamycin (RAPA), an mTOR pathway inhibitor, has limited effectiveness in promoting lesion regression in patients with TEK receptor tyrosine kinase (TIE2)-mutated VMs. This may be due to poor bioavailability, frequent dosing requirements, and off-target effects that make maintaining adherence difficult. Recent preclinical studies have shown that combination treatment with RAPA and a c-ABL inhibitor [ponatinib (PON)] resulted in regression of VMs in a murine model; however, daily oral dosing was required. Here, we describe the formulation of polymeric RAPA, which acts as both a polymeric drug and a drug delivery carrier. The polymer was synthesized by polymerization of methacryloylated RAPA and terminated with polyethylene glycol (PEG-pRAPA). PEG-pRAPA self-assembled to form 30-nanometer nanoparticles (PEG-pRAPA NPs) and enabled the encapsulation of PON (PEG-pRAPA@PON NPs). PEG-pRAPA@PON NPs provided sustained release of both PON and PEG-pRAPA in vitro, reducing AKT phosphorylation comparably to free RAPA and PON. In a murine model of VMs, a single intravenous dose of PEG-pRAPA@PON NPs caused 70% VM regression over 20 days and a 6.3-fold reduction in CD31-positive (human-derived) blood vessels. There was no evidence of systemic toxicity or organ dysfunction after treatment. These findings demonstrated that PEG-pRAPA is an effective polymeric drug and drug delivery platform and support the hypothesis that nanoparticle-based pharmacotherapy can be an effective treatment strategy for VMs.

Plasma protein quantitative trait loci (pQTLs) have been integrated with genetic studies to prioritize proteins implicated in numerous human diseases. However, limited interaction between plasma and the central nervous system decreases the fluid's relevance for neurological disease. We compared the pQTL landscapes between plasma and cerebrospinal fluid (CSF), detecting widespread differences across fluids that translate to the identification and prioritization of proteins and pathways implicated in neurological disorders. Of almost 5000 CSF and plasma pQTLs, fewer than 30% were present in both fluids, demonstrating the importance of cross-context analyses to understand genetic regulation of protein abundance. We identified 427 associations between proteins and risk of 14 neurological traits, including 249 associations that were not found in previous studies. Only 69 of the associations were consistently detected in both fluids, demonstrating the information gained through the analysis of multiple bodily contexts. We further demonstrated that CSF proteogenomics captures more substantial disease overlap (for example, between Alzheimer's disease and dementia with Lewy bodies) and captures trait-relevant biology missed in plasma, including cell death and immune response signatures in Alzheimer's and multiple sclerosis. Through this work, we demonstrated the importance of analyzing less accessible but more trait-relevant contexts to fully understand human disease.

The clinical success of chimeric antigen receptor T cell (CAR T cell) therapy in hematologic malignancies has prompted its application for refractory solid tumors, including glioblastoma (GBM). However, CAR T cell trials against solid tumors have failed to show clinical efficacy thus far. Here, we show that the dysfunction of CAR T cells in GBM is attributed, at least, in part, to glucose deficiency in the tumor microenvironment (TME) driven by the substantial consumption of glucose by cancer cells. Engineering CAR T cells to continuously express glucose transporter 3 (GLUT3), a high-affinity glucose transporter, restored their cytokine production and killing activity. However, although CAR T cells with stable GLUT3 expression induced tumor reduction in a preclinical GBM model, their overactivation led to adverse events and mouse death. In contrast, on-demand GLUT3-expressing CAR T cells, in which GLUT3 transcription was driven by the nuclear translocation of nuclear factor of activated T cells (NFAT) as a consequence of target antigen stimulation, exhibited enhanced metabolic fitness and increased antitumor efficacy, leading to long-lasting tumor control in intracranial human GBM cell xenograft models while preventing adverse events. We propose that on-demand enhancement of metabolic fitness, such as at the time of exposure to tumor antigens, is a concept for boosting the antitumor efficacy of CAR T cells against solid tumors.

Venezuelan (VEEV), eastern (EEEV), and western (WEEV) equine encephalitis viruses are alphaviruses from different serocomplexes that cause neurological disease in humans. Given their antigenic distance, it has been challenging to isolate cross-reactive antibodies that neutralize infection by multiple medically relevant encephalitic alphaviruses. Recently, distinct entry receptors were identified for these encephalitic alphaviruses: LDLRAD3 for VEEV, VLDLR for EEEV and some strains of WEEV, and PCDH10 for WEEV. Here, using structure-guided mutagenesis, we generated a soluble chimeric protein derived from the LA1 domain of LDLRAD3 and the LA2 domain of VLDLR, termed LDLRAD3-vLA1-VLDLR-LA2, which neutralized infection by VEEV, EEEV, and some WEEV strains in cell culture and protected mice from infection. Structural analysis of this engineered decoy revealed binding to distinct sites on each virus, which corresponded to those engaged by their endogenous entry receptors. We extended the neutralizing and protective capacity to contemporary WEEV strains by adding a single extracellular cadherin domain from sparrow PCDH10 through a stabilized symmetric bispecific decoy scaffold. Our designed receptor decoy serves as a possible countermeasure against multiple encephalitic alphaviruses, and this design platform could be harnessed to develop therapeutic agents against viruses from other families.

Steroid-resistant acute graft-versus-host disease (SR-aGVHD) is the leading life-threatening complication after allogeneic hematopoietic stem cell transplantation. Therapeutic development is impeded by scarce knowledge of biological pathways leading to steroid resistance after aGVHD diagnosis. To gain insight into circulating immune cell subsets and their functions at the onset of aGVHD, we performed a single-cell deep phenotyping and transcriptome analysis on peripheral blood mononuclear cells from two cohorts of patients (discovery cohort, n=53; and validation cohort, n=32) with aGVHD before steroid treatment or without aGVHD. Frequencies of circulating immune subsets were not associated with steroid resistance. However, pathway analysis and inferred ligand-receptor interactions revealed major functional divergences between steroid-sensitive aGVHD (SS-aGVHD) and SR-aGVHD, suggesting that steroid resistance is an intrinsic property of immune cells before any treatment. SR-aGVHD was mainly associated with tumor necrosis factor-α (TNF-α) activation. Steroid resistance resulted from a specific cross-talk characterized by inflammasome and caspase-1 activation in monocyte subsets; by TNF-α/TNF receptor, interleukin-1β (IL-1β), IL-18, CCL3, and CCL4 signaling between myeloid and T cells; and by lower involvement of interferon-α and interferon-γ signaling pathways. Immune trajectories in CD8+ T cells demonstrated a direct transition from an early naïve state to a highly activated one. By contrast, SS-aGVHD involved gene signatures across multiple intermediate differentiation stages during cell-to-cell transitions into CD8+ T subsets. These findings provide evidence that steroid resistance is driven by intrinsic mechanisms already present at the onset of the alloimmune response, which may enable previously unknown therapeutic strategies.

A simple intervention called E-MOTIVE can save a mother's life by helping to manage bleeding after childbirth.

For many years, research focused on the immune system's role in the development of type 1 diabetes (T1D). However, mounting evidence suggests a critical involvement of intrinsic pancreatic β cell defects, particularly impaired cellular stress responses, in disease pathology. This shift in understanding is supported by the limited effectiveness of immune-targeting therapies, which have so far managed to delay, rather than prevent or cure, T1D. Here, we discuss why the immune system specifically targets β cells, how stress pathways modify the interaction between β cells and immune cells, β cell resilience, and challenges and opportunities in targeting β cell stress in T1D.

Targeted therapies are important for invasive breast cancer (IBC) treatment but are generally not standard of care in the neoadjuvant setting. To identify therapies with the potential to improve neoadjuvant treatment response, it is essential to develop patient-derived preclinical models that faithfully reflect the diversity of primary IBC subtypes in patients. Here, we generated and characterized a large-scale cohort of 60 mouse-intraductal patient-derived xenograft (MIND-PDX) models representing all subtypes of primary IBC, as well as seven matched PDX-derived organoids. We showed that our IBC-MIND cohort can serve as a platform for preclinical evaluation of experimental neoadjuvant treatments. For triple-negative IBC, we demonstrated that neoadjuvant treatment does not benefit from addition of a PARP inhibitor, whereas for estrogen receptor-positive IBC, the combination of a CDK4/6 inhibitor and fulvestrant improved neoadjuvant treatment response. Our work provides a valuable resource of primary IBC models to study breast cancer biology and develop neoadjuvant treatments.

Metastasis is the leading cause of death in patients with breast cancer (BC), but the mechanisms underlying metastasis formation are still poorly understood. Circulating tumor cells (CTCs) are considered the main seed of metastasis with demonstrated prognostic impact in patients with BC. They are conventionally identified as cells positive for epithelial markers and lacking leukocyte markers. Nonetheless, circulating cells expressing both markers [dual-positive cells (DPcells)] have been reported but poorly investigated. Here, we evaluated, in a cohort of 340 patients with advanced BC, the prognostic impact of DPcells, showing their association with worse survival, particularly in patients with less than five CTCs. Their prognostic value varied among BC subtypes, with greater relevance observed in triple-negative and HER2-positive BC. Moreover, by performing single-cell genomic profiling of DPcells isolated from patients, we detected genomic aberrations in 28 and 93% of analyzed DPcells and CTCs, respectively. In vivo, DPcells were detected only in the blood of immunocompetent but not immunodeficient mice and no differences in the lung metastatic colonization ability of DPcells versus control cancer cells were observed. Our findings highlight the importance of studying this overlooked subpopulation of CTCs as a prognostic biomarker in BC, which might be particularly important in specific BC subtypes. Moreover, our results support the malignancy and metastasis-forming capability of DPcells and underline the need for future studies better defining the origin of these cells.