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Post-transplantation, T helper 1 (Th1)-mediated immune rejection is the predominant cause of graft failure. Th1 cell sensitization occurs through complex and context-dependent interaction among antigen-presenting cell subsets, particularly CD11b+ dendritic cells (DC2) and CD103+ dendritic cells (DC1). This interaction necessitates further investigation in context of transplant immunity. We use a well-established pre-clinical models of corneal transplantation and identified distinct roles of migratory CD103+ DC1 in influencing the outcomes of the grafted tissue. In recipients with uninflamed corneal beds, migratory CD103+DC1 demonstrate a tolerogenic phenotype that modulate the immunogenic capacity of CD11b+DC2 primarily mediated by IL-10, suppressing alloreactive CD4+Th1 cells via the PD-L1/PD-1 pathway, and enhancing Treg-mediated tolerance via αvβ8 integrin-activated TGFβ1, thus facilitating graft survival. Conversely, in recipients with inflamed and vascularized corneal beds, IFN-γ produced by CD4+Th1 cells induces migratory CD103+DC1 to adopt an immunostimulatory phenotype, characterized by the downregulation of regulatory markers including αvβ8 integrin and IL-10 and the upregulation of IL-12 and costimulatory molecules CD80/86, resulting in graft failure. The adoptive transfer of ex-vivo induced tolerogenic CD103+DC1(iDC1) effectively inhibits Th1 polarization and preserves the tolerogenic phenotype of their physiological counterparts. Collectively, our findings underscore the essential role played by CD103+DC1 in modulating host alloimmune responses.

Our objective was to interrogate infant mesenchymal stem cell (MSC) lipid metabolism and gestational exposures that may contribute to child obesity risk. MSCs were cultured from term infants of mothers with obesity (n=16) or normal-weight (n=15). In MSCs undergoing myogenesis in vitro, we used lipidomics to distinguish phenotypes by unbiased cluster analysis and lipid challenge (24h excess fatty acid, 24hFA). We measured MSC AMP-activated protein kinase (AMPK) activity and fatty acid oxidation (FAO), and a composite index of maternal glucose, insulin, triglycerides, free fatty acids, tumor necrosis factor-α, high density lipoprotein- and total- cholesterol in fasting blood from mid- and late-gestation (~17, ~27wks). We measured child adiposity at birth (n=29), 4-6m (n=29), and 4-6y (n=13). Three MSC clusters were distinguished by triacylglycerol (TAG) stores, with greatest TAGs in Cluster-2. All Clusters increased acylcarnitines and TAGs with 24hFA, though Cluster-2 was more pronounced and corresponded to AMPK activation and FAO. Maternal metabolic markers predicted MSC Clusters and child adiposity at 4-6y (both highest in Cluster-3). Our data supports that MSC phenotypes are predicted by comprehensive maternal metabolic milieu exposures, independent of maternal BMI, and suggest utility as an at-birth predictor for child adiposity, though validation with larger longitudinal samples is warranted.

In patients who progress from acute hepatitis B virus (HBV) infection to a chronic HBV (CHB) infection, CD8+ T cells fail to eliminate the virus and become impaired. A functional cure of CHB likely requires new and highly functional CD8+ T cell responses different from those induced by the infection. Here we report preclinical immunogenicity and efficacy of an HBV therapeutic vaccine that includes herpes simplex virus (HSV) glycoprotein D (gD), a checkpoint modifier of early T cell activation, that enhances, broadens, and prolongs CD8+ T cell responses. We developed a therapeutic HBV vaccine based on a chimpanzee adenovirus serotype 6 (AdC6) vector, called AdC6-gDHBV2, that targets conserved and highly immunogenic regions of the viral polymerase (pol) and core antigens fused into HSV gD. The vaccine was tested with, and without gD, in mice for immunogenicity and in an adeno-associated virus (AAV)8-1.3HBV vector model for antiviral efficacy. The vaccine encoding the HBV antigens within gD stimulates potent and broad CD8+ T cell responses. In a surrogate model of HBV infection, a single intramuscular (i.m.) injection of AdC6-gDHBV2 achieved significant and sustained declines of circulating HBV DNA copies (cps) and HBV surface antigen (HBsAg); both inversely correlated with HBV specific CD8+ T cell frequencies in spleens and livers. AdC6-gDHBV2 is the first therapeutic vaccine to show significant reductions in levels of HBV genome copies and HBsAg when used alone, even when vaccination was delayed for months from infection.

The prevalence of chronic kidney diseases (CKD) varies by race due to genetic and environmental factors. The Glu504Lys polymorphism in aldehyde dehydrogenase 2 (ALDH2), commonly observed among East Asians, alters the enzyme's function in detoxifying alcohol-derived aldehydes, impacting kidney function. This study investigated the association between variations in ALDH2 levels within the kidney and the progression of kidney fibrosis. Our clinical data indicates that diminished ALDH2 levels are linked to worse CKD outcomes, with correlations between ALDH2 expression, estimated glomerular filtration rate, urinary levels of acrolein, an aldehyde metabolized by ALDH2, and fibrosis severity. In mouse models of unilateral ureteral obstruction and folic acid nephropathy, reduced ALDH2 levels and elevated acrolein were observed in kidneys, especially in ALDH2 Glu504Lys knock-in mice. Mechanistically, acrolein modifies pyruvate kinase M2, leading to its nuclear translocation and co-activation of HIF-1α, shifting cellular metabolism to glycolysis, disrupting mitochondrial function, contributing to tubular damage and the progression of kidney fibrosis. Enhancing ALDH2 expression through adeno-associated virus vectors reduces acrolein and mitigates fibrosis in both wild-type and Glu504Lys knock-in mice. These findings underscore the potential therapeutic significance of targeting the dynamic interaction between ALDH2 and acrolein in CKD.

Ataxia telangiectasia and Rad3-related protein (ATR) is a key DNA damage response protein that facilitates DNA damage repair and regulates cell cycle progression. As such, ATR is an important component of the cellular response to radiation, particularly in cancer cells which show altered DNA damage response and aberrant cell cycle checkpoints. Therefore, ATR's pharmacological inhibition could be an effective radiosensitization strategy to improve radiotherapy. We assessed the ability of an ATR inhibitor, AZD6738, to sensitize cancer cell lines of various histologic types to photon and proton radiotherapy. We found that radiosensitization took place through persistent DNA damage and abrogated G2 cell cycle arrest. We also found that AZD6738 increased the number of micronuclei after exposure to radiotherapy. We found that combining radiation with AZD6738 led to tumor growth delay and prolonged survival relative to radiation alone in a breast cancer model. Combining AZD6738 with photons or protons also led to increased macrophage infiltration at the tumor microenvironment. These results provide a rationale for further investigation of ATR inhibition in combination with radiotherapy and with other agents such as immune checkpoint blockade.

Background: Immune processes are influenced by circadian rhythms. We evaluate the association between varicella vaccine administration time-of-day and vaccine effectiveness.

Methods: A national cohort, children < 6 years were enrolled between January 2002 to December 2023. We compared children vaccinated during morning (7:00-10:59), late-morning to afternoon (11:00-15:59), or evening hours (16:00-19:59). A Cox proportional-hazards regression model was used to adjust for ethnicity, sex, and comorbidities. The first varicella infection occurring at least 14 days after vaccination, or a second dose administration were treated as a terminal event.

Results: 4,501 (1.8%), of 251,141 vaccinated children, experienced breakthrough infections. Infection rates differed based on vaccination time, with the lowest rates associated with late-morning to afternoon (11:00-15:59), HR 0.88, 95% CI 0.82-0.95, P < 0.001, and the highest rates with evening vaccination (16:00-19:59), HR 1.41, 95% CI 1.32-1.52, P < 0.001. Vaccination timing remained significant after adjustment for ethnicity, sex, and comorbidities. The association between immunization time and infection risk followed a sinusoidal pattern, consistent with a diurnal rhythm in vaccine effectiveness.

Conclusions: We report a significant association between the time of varicella vaccination and its clinical effectiveness. Similar association was observed with the COVID-19 vaccine, providing proof of concept consistent with a diurnal rhythm in vaccine effectiveness.

Dual endothelin-1 (ET-1) and angiotensin II (AngII) receptor antagonism with sparsentan has strong antiproteinuric actions via multiple potential mechanisms that are more pronounced, or additive compared to current standard of care using angiotensin receptor blockers (ARB). Considering the many actions of ET-1 and AngII on multiple cell types, this study aimed to determine glomeruloprotective mechanisms of sparsentan compared to the ARB losartan by direct visualization of its effects in the intact kidney in focal segmental glomerulosclerosis (FSGS) using intravital multiphoton microscopy. In both healthy and FSGS models, sparsentan treatment increased afferent/efferent arteriole diameters, increased or preserved blood flow and single nephron glomerular filtration rate, attenuated acute ET-1+AngII-induced increases in podocyte calcium, reduced proteinuria, preserved podocyte number, increased both endothelial and renin lineage cells and clones in vasculature, glomeruli and tubules, restored glomerular endothelial glycocalyx, attenuated mitochondrial stress and immune cell homing. These effects were either not observed or of smaller magnitude with losartan. The pleiotropic nephroprotective effects of sparsentan included improved hemodynamics, podocyte and endothelial cell functions, and tissue repair. Compared to losartan, sparsentan was more effective in the sustained preservation of kidney structure and function, which underscores the importance of the ET-1 component in FSGS pathogenesis and therapy.

The accumulation of mutant huntingtin protein aggregates in neurons is a pathological hallmark of Huntington's disease (HD). The glymphatic system, a brain-wide perivascular network, facilitates the exchange of interstitial fluid (ISF) and cerebrospinal fluid (CSF), supporting interstitial solute clearance of brain wastes. In this study, we employed dynamic glucose-enhanced (DGE) MRI to measure D-glucose clearance from CSF as a tool to predict glymphatic function in a mouse model of HD. We found significantly diminished CSF clearance efficiency in HD mice prior to phenotypic onset. The impairment of CSF clearance efficiency worsened with disease progression. These DGE MRI findings in compromised glymphatic function were further confirmed with fluorescence-based imaging of CSF tracer influx, suggesting an impaired glymphatic function in premanifest HD. Moreover, expression of the astroglial water channel aquaporin-4 (AQP4) in the perivascular compartment, a key mediator of glymphatic function, was significantly diminished in both HD mouse brain and human HD brain. Our data, acquired using a clinically translatable MRI, indicate a perturbed glymphatic network in the HD brain. Further validation of these findings in clinical studies will provide insights into the potential of glymphatic clearance as a therapeutic target as well as an early biomarker in HD.

Background: Prostate cancer (PC) is driven by aberrant signaling of the androgen receptor (AR) or its ligands, and androgen deprivation therapies (ADT) are a cornerstone of treatment. ADT responsiveness may be associated with germline alterations in genes that regulate androgen production, uptake, and conversion (APUC).

Methods: We analyzed whole-exome sequencing (WES) and whole transcriptome sequencing (WTS) data from prostate tissues (SU2C/PCF, TCGA, GETx). We also interrogated the Caris POA DNA (592-gene/whole exome) and RNA (whole transcriptome) NGS databases. Algorithm for Linking Activity Networks (ALAN) was used to quantify all pairwise gene-to-gene associations. Real-world overall survival (OS) was determined from insurance claims data using Kaplan-Meier estimates.

Results: Six APUC genes (HSD3B1, HSD3B2, CYP3A43, CYP11A1, CYP11B1, CYP17A1) exhibited coalescent gene behavior in a cohort of metastatic tumors (n = 208). In the Caris POA dataset, the 6 APUC genes (APUC-6) exhibited robust clustering in primary prostate (n = 4,490) and metastatic (n = 2,593) biopsies. Surprisingly, tumors with elevated APUC-6 expression had statically lower expression of AR, AR-V7, and AR signaling scores suggesting ligand-driven disease biology. APUC-6 genes instead associated with the expression of alternative steroid hormone receptors, ESR1/2 and PGR. We used RNA expression of AR or APUC-6 genes to define two subgroups of tumors with differential association with hallmark pathways and cell surface targets.

Conclusions: The APUC-6 high/AR-low tumors represented a subgroup of patients with good clinical outcomes in contrast to the AR-high or neuroendocrine prostate cancers. Altogether, measuring the aggregate expression of APUC-6 genes in current genomic tests identifies PCs that are ligand- (rather than AR-) driven and require distinct therapeutic strategies.

Funding: NCI/NIH 1R37CA288972-01, NCI Cancer Center Support P30 CA077598, DOD W81XWH-22-2-0025, R01 CA249279.

Therapeutics that rescue folding, trafficking, and function of disease-causing missense mutants are sought for a host of human diseases, but efforts to leverage model systems to test emerging strategies have met with limited success. Such is the case for Niemann-Pick type C1 disease, a lysosomal disorder characterized by impaired intracellular cholesterol trafficking, progressive neurodegeneration, and early death. NPC1, a multipass transmembrane glycoprotein, is synthesized in the endoplasmic reticulum and traffics to late endosomes/lysosomes, but this process is often disrupted in disease. We sought to identify small molecules that promote folding and enable lysosomal localization and functional recovery of mutant NPC1. We leveraged a panel of isogenic human induced neurons expressing distinct NPC1 missense mutations. We used this panel to rescreen compounds that were reported previously to correct NPC1 folding and trafficking. We established mo56-hydroxycholesterol (mo56Hc) as a potent pharmacological chaperone for several NPC1 mutants. Furthermore, we generated mice expressing human I1061T NPC1, a common mutation in patients. We demonstrated that this model exhibited disease phenotypes and recapitulated the protein trafficking defects, lipid storage, and response to mo56Hc exhibited by human cells expressing I1061T NPC1. These tools established a paradigm for testing and validation of proteostatic therapeutics as an important step towards the development of disease-modifying therapies.