Effect of second booster vaccinations and prior infection against SARS-CoV-2 in the UK SIREN healthcare worker cohort

Background

The protection of fourth dose mRNA vaccination against SARS-CoV-2 is relevant to current global policy decisions regarding ongoing booster roll-out. We aimed to estimate the effect of fourth dose vaccination, prior infection, and duration of PCR positivity in a highly-vaccinated and largely prior-COVID-19 infected cohort of UK healthcare workers.

Methods

Participants underwent fortnightly PCR and regular antibody testing for SARS-CoV-2 and completed symptoms questionnaires. A multi-state model was used to estimate vaccine effectiveness (VE) against infection from a fourth dose compared to a waned third dose, with protection from prior infection and duration of PCR positivity jointly estimated.

Findings

1298 infections were detected among 9560 individuals under active follow-up between September 2022 and March 2023. Compared to a waned third dose, fourth dose VE was 13.1% (95% CI 0.9 to 23.8) overall; 24.0% (95% CI 8.5 to 36.8) in the first 2 months post-vaccination, reducing to 10.3% (95% CI -11.4 to 27.8) and 1.7% (95% CI -17.0 to 17.4) at 2-4 and 4-6 months, respectively. Relative to an infection >2 years ago and controlling for vaccination, 63.6% (95% CI 46.9 to 75.0) and 29.1% (95% CI 3.8 to 43.1) greater protection against infection was estimated for an infection within the past 0-6, and 6-12 months, respectively. A fourth dose was associated with greater protection against asymptomatic infection than symptomatic infection, whilst prior infection independently provided more protection against symptomatic infection, particularly if the infection had occurred within the previous 6 months. Duration of PCR positivity was significantly lower for asymptomatic compared to symptomatic infection.

Interpretation

Despite rapid waning of protection, vaccine boosters remain an important tool in responding to the dynamic COVID-19 landscape; boosting population immunity in advance of periods of anticipated pressure, such as surging infection rates or emerging variants of concern.

Funding

UK Health Security Agency, Medical Research Council, NIHR HPRU Oxford, Bristol, and others.

Early Warning Surveillance for SARS-CoV-2 Omicron Variants, United Kingdom, November 2021-September 2022

Since June 2020, the SARS-CoV-2 Immunity and Reinfection Evaluation (SIREN) study has conducted routine PCR testing in UK healthcare workers and sequenced PCR-positive samples. SIREN detected increases in infections and reinfections and delected Omicron subvariant waves emergence contemporaneous with national surveillance. SIREN's sentinel surveillance methods can be used for variant surveillance.

Oncolytic Viral Therapy Mediates its Effectiveness by Inducing and Enhancing CD4 cytotoxic T-cells

Malignant glioma remains a fatal disease with a dismal survival rate. To address this urgent medical need, we pioneered the concept of engineered oncolytic viruses for cancer. Using the herpes simplex virus (HSV)-1 as an experimental virus, our published Phase I trials have demonstrated the safety and efficacy of such oHSV-based therapy for treating brain tumor patients. In searching for biomarkers for better responses to this therapy, our preclinical studies using intracranial glioma models and an oHSV secreting murine IL-12 (M002) revealed that a subset of CD4+ T-cells expressing the cytolytic signatures, including granzyme B, were increased in M002-treated mice compared to vehicle-treated controls. Correspondingly, CD4+ T-cells isolated from brain tumors of M002-treated mice killed tumor cells better than cells isolated from control tumors. However, the factors and temporal requirements that direct the development of this CD4 cytotoxic T-cell (CTL) subset are not fully understood. To address this question, we performed single-cell RNA sequencing analysis of CD4+ T-cells isolated from brain tumors of M002-treated and control mice. The results revealed a complex change of the CD4+ T-cell compartment with CD4 CTLs being induced from two different precursors. The first CTL subset was derived from T helper-1 (Th1) cells and retained Th1 gene signatures while expressing high levels of CTL associated molecules. The second CTL subset was a reprogrammed regulatory T-cell population capable of producing high levels of cytokines and granzymes. Both CD4 CTL subsets were more prominent in M002-treated mice, suggesting that M002 therapy could induce CD4 CTLs with specialized functionality, which may account for its improved outcome.

Supported by grants from DoD  W81XH-18-1-0315 and UAB Start up Funds

IMMU-09. HUMAN MICROBIOTA INFLUENCE THE EFFICACY OF IMMUNOTHERAPY IN A MOUSE MODEL OF GLIOBLASTOMA

Although immunotherapy works well in glioblastoma (GBM) pre-clinical mouse models, the therapy has unfortunately not demonstrated efficacy in humans. In melanoma and other cancers, the composition of the gut microbiome has been shown to determine responsiveness or resistance to immune checkpoint inhibitors (anti-PD-1). Most pre-clinical cancer studies have been done in mouse models using mouse gut microbiomes, but there are significant differences between mouse and human microbial gut compositions. To address this inconsistency, we developed a novel humanized microbiome (HuM) model to study the response to immunotherapy in a pre-clinical mouse model of GBM. We used five healthy human donors for fecal transplantation of gnotobiotic mice. After the transplanted microbiomes stabilized, the mice were bred to generate five independent humanized mouse lines (HuM1-HuM5). Analysis of shotgun metagenomic sequencing data from fecal samples revealed a unique microbiome with significant differences in diversity and microbial composition among HuM1-HuM5 lines. Interestingly, we found that the HuM lines responded differently to anti-PD-1. Specifically, we demonstrate that HuM2 and HuM3 mice are responsive to anti-PD-1 and displayed significantly increased survival compared to isotype controls, while HuM1, HuM4, and HuM5 mice are resistant to anti-PD-1. These mice are genetically identical, and only differ in the composition of the gut microbiome. In a correlative experiment, we found that disrupting the responder HuM2 microbiome with antibiotics abrogated the positive response to anti-PD-1, indicating that HuM2 microbiota must be present in the mice to elicit the positive response to anti-PD-1 in the GBM model. The question remains of whether the “responsive” microbial communities in HuM2 and HuM3 can be therapeutically exploited and applicable in other tumor models, or if the “resistant” microbial communities in HuM1, HuM4, and HuM5 can be depleted and/or replaced. Future studies will assess responder microbial transplants as a method of enhancing immunotherapy.

Identifying a molecular profile to predict the risk of recurrence in high-intermediate risk endometrial cancer

Background

Patients with high‐intermediate risk endometrial cancer (H‐IR EMCA) have an elevated risk of recurrence compared to low‐risk counterparts. Many H‐IR EMCA patients are treated with radiation or chemotherapy, but their overall survival is not significantly impacted by treatment. The objective of this study was to compare molecular profiles of H‐IR EMCA patients with disease recurrence to those without to identify characteristics that could better predict patient outcomes.

Methods

Tissue was acquired from H‐IR EMCA patients with disease recurrence (n=15) and without disease recurrence (n=15) who had not received adjuvant therapy and performed DNA and RNA analyses.

Results

In recurrent population, 5 patients had matchingrecurrent and initial tumor tissues. Of note, 5/7 (71%) African Americanpatients had disease recurrence compared to 10/23 (43%) White patients. Inaddition, several new mutations were found in individual patient’s recurrentcompared to initial tumors.

Conclusions

Currently the treatment ofendometrial cancer is rapidly changing with molecular profiling becoming partof the standard of care. Additionally, it and is being incorporated intoclinical trials in this group of patients. The specific gene mutations and RNAexpression signatures that were observed in our small cohort need to bevalidated in larger cohorts to determine their impact.

Vitamin D and Lumisterol Hydroxyderivatives Can Act on Liver X Receptors (LXRs)

New pathways of vitamin D3 (D3) activation initiated by CYP11A1 and involving other CYPs have been discovered. At least 15 hydroxyderivatives, including 20(OH)D3 as the major product, are generated by these pathways (1,2) with some being present in human serum, epidermis, and pig adrenals. CYP11A1 can also metabolize 7-dehydrocholesterol to produce 7-dehydropregnenolone, which can be further modified by steroidogenic enzymes generating Δ7-steroids (1,2). Lastly, CYP11A1 and CYP27A1 act on lumisterol (L3) producing at least 9 biologically active derivatives (1,2). Thus, new pathways generating a large number of biologically active secosteroids and lumisterol-derivatives have now been described. These compounds interact with the vitamin D receptor (VDR), retinoic acid receptors (RORs) α and γ, and the aryl hydrocarbon receptor (AhR)(1). These findings challenge dogmas that lumisterol is biologically inactive and that 1,25(OH)2D3 is the only active form of D3 exerting its effects exclusively through interaction with the VDR. In view of the above and since liver X receptors (LXRs) can be activated by oxysterols, we investigated the interactions of novel products of L3 and D3 metabolism with LXRs. Molecular docking, using crystal structures of the ligand binding domains (LBDs) of LXRα and β, revealed high docking scores for L3 and D3 hydroxymetabolites, like those of the natural ligands, predicting good receptor binding. RNA sequencing of murine dermal fibroblasts stimulated with D3-hydroxyderivatives revealed LXR as the second major nuclear receptor signaling pathway for several D3-hydroxyderivatives, including 1,25(OH)2D3. The involvement of LXRs was validated by the induction of several genes downstream of LXR. Furthermore, L3 and D3-hydroxyderivatives activated an LXR-response element (LXRE)-driven reporter in CHO cells and human keratinocytes. For keratinocytes, enhanced expression of LXR target genes was also observed supporting the involvement of LXR. Importantly, L3 and D3 derivatives showed high affinity binding to the LBD of the LXRα and β in LanthaScreen TR-FRET LXRα and β coactivator assays. The majority of metabolites functioned as LXRα/β agonists; however, 1,20,25(OH)3D3, 1,25(OH)2D3, 1,20(OH)2D3 and 25(OH)D3 acted as inverse agonists of LXRα, but as agonists of LXRβ. Molecular dynamics simulations performed for selected compounds, including 1,25(OH)2D3, 1,20(OH)2D3, 25(OH)D3, 20(OH)D3, 20(OH)L3 and 20,22(OH)2L3, showed overlapping and different interactions with LXRs. Identification of D3 and L3 derivatives as ligands for LXRs changes the accepted paradigms on their biological role and mechanism of action. 1. Cell Biochem Biophys. 2020;78(2):165-180. 2. J Steroid Biochem Mol Biol. 2019;186:4-21.

Understanding the effect of mechanical forces on ovarian cancer progression

OBJECTIVE

Mechanical forces including tension, compression, and shear stress are increasingly implicated in tumor progression and metastasis. Understanding the mechanisms behind epithelial ovarian cancer (EOC) progression and metastasis is critical, and this study aimed to elucidate the effect of oscillatory and constant tension on EOC.

METHODS

SKOV-3 and OVCAR-8 EOC cell lines were placed under oscillatory tension for 3 days and compared to cells placed under no tension. Cell proliferation, migration, and invasion were analyzed while RNAseq and Western Blots helped investigate the biological mechanisms underlying the increasingly aggressive state of the experimental cells. Finally, in vivo experiments using SCID mice assisted in confirming the in vitro results.

RESULTS

Oscillatory tension (OT) and constant tension (CT) significantly increased SKOV-3 proliferation, while OT caused a significant increase in proliferative genes, migration, and invasion in this cell line. CT did not cause significant increases in these areas. Neither OT nor CT increased proliferation or invasion in OVCAR-8 cells, while both tension types significantly increased cellular migration. Two proteins involved in metastasis, E-cadherin and Snail, were both significantly affected by OT in both cell lines, with E-cadherin levels decreasing and Snail levels increasing. In vivo, tumor growth and weight for both cell types were significantly increased, and ascites development was significantly higher in the experimental OVCAR-8 group than in the control group.

CONCLUSIONS

This study found that mechanical forces are influential in EOC progression and metastasis. Further analysis of downstream mechanisms involved in EOC metastasis will be critical for improvements in EOC treatment.

TMOD-19. INDIVIDUAL SPECIFIC HUMAN GUT MICROBE COMMUNITIES INFLUENCE RESPONSE TO IMMUNOTHERAPY IN A HUMANIZED MICROBIOME MOUSE MODEL OF GLIOMA

Although immunotherapy works well in glioblastoma (GBM) pre-clinical mouse models, the therapy has not demonstrated efficacy in GBM patients. Since recent studies have linked the gut microbial composition to the success with immunotherapy for other cancers, we utilized a novel humanized microbiome (HuM) model in order to study the response to immunotherapy in a pre-clinical mouse model of GBM. We used five healthy human donors for fecal transplantation of gnotobiotic mice since it is now recognized that microbe strain level differences render individual humans with a unique microbial community composition. After the transplanted microbiomes stabilized, the mice were bred to generate 5 independent humanized mouse lines (humanized microbiome HuM1-HuM5). Analysis of shotgun metagenomic sequencing data from fecal samples revealed a unique microbiome composition with significant differences in diversity and microbial composition among HuM1-HuM5 lines. We next analyzed the growth of intracranial glioma cells in the HuM lines. All HuM mouse lines were susceptible to GBM transplantation, and exhibited similar median survival ranging from 19-26 days. Interestingly, we found that HuM lines responded differently to the immune checkpoint inhibitor anti-PD-1. Specifically, we demonstrate that HuM1, HuM4, and HuM5 mice are non-responders to anti-PD-1 resulting in the death of the mice from the intracranial tumors, while HuM2 and HuM3 mice are responsive to anti-PD-1 and displayed significantly increased survival compared to isotype controls. Bray-Curtis cluster analysis of the 5 HuM gut microbial communities revealed that HuM2 and HuM3 were closely related. Detailed taxonomic comparison analysis at the top 5 across all HuM mouse lines revealed that Bacteroides cellulosilyticus was commonly found between HuM2 and HuM3 with high abundances. The results of our study establish the utility of humanized microbiome mice as avatars to delineate features of the host interaction with gut microbe communities needed for effective immunotherapy against GBM.

TAMI-39. AGE-DEPENDENT PHENOTYPIC CONVERSION FROM NEURONAL ACTIVITY TO NEURO-INFLAMMATION IN GLIOBLASTOMA PROGRESSION

The rise in population aging worldwide is causing an unparalleled increase in death from many cancers, including glioblastoma (GBM). Here, we have explored the impact of aging and rejuvenation on GBM tumorigenesis. Compared with neuro-inflammatory old GBM, young GBM displayed elevated neuronal/synaptic signaling via brain-derived neurotrophic factor (BDNF) and SLIT and NTRK like-family member 6 (SLITRK6), promoting favorable survival rates. These effects were attributed to the rise in nicotinamide adenine dinucleotide (NAD+) levels, as brain rejuvenation by parabiosis or administration of nicotinamide mononucleotide (NMN) in mice elicited a younger phenotype with activated neuronal/synaptic signaling and improved outcomes. Our data indicate that age-associated NAD+ loss contributes to the highly aggressive GBM by the shift from neuronal/synaptic activity to neuro-inflammation in the elderly brain. These findings have therapeutic and preventive implications in GBM and provide mechanistic insights into the exacerbation of GBM tumorigenesis by aging.

Abstract 4568: The One Health Consortium and combination immunotherapy: evaluating M032, a genetically engineered HSV-1 expressing Il-12, in combination with a checkpoint inhibitor in canine glioma patients

Introduction: Malignant gliomas are the most common primary brain tumors in humans, accounting for approximately 30% of all primary CNS tumors in adults (Levin et al., 2001). Interestingly, pet dogs spontaneously and sporadically develop malignant glial brain tumors that resemble high-grade gliomas in humans; with similar incidence, treatments, and outcome patterns. (Priester and McKay, 1980; Snyder et al., 2006; Ostrom et al., 2013; Ostrom et al., 2014; Hicks et al., 2017) The most malignant of these tumors have been refractory to limited treatment options. Despite aggressive treatment, outcomes are dismal with median survivals just over one year in humans and two months in dogs. Novel treatments are greatly needed and combination therapies appear to hold promise.

Background: This pre-clinical protocol, a dose-escalating phase I study in dogs with sporadic malignant glioma, represents a first in comparative oncology and combination immunotherapy. The trial is evaluating M032, an Interleukin-12 expressing Herpes Simplex virus, alone and combined with a checkpoint inhibitor, Indoximod. Note, prior studies have demonstrated human IL-12 to generate effective anti-tumoral response in canine patients (Pavlin et al., 2012). M032 is currently being tested in humans with high-grade malignant gliomas. Thus, in a novel fashion, both canine and human trials are proceeding concurrently, allowing a direct “head-to-head” comparison of safety and efficacy.

Methods: Stage 1 of the trial, which is presently ongoing, involves catheter-based administration of MO32 alone into the tumor resection cavity at escalating doses in subsequent cohorts of dogs to establish maximum tolerable dose (MTD), detect dose limiting toxicities (DLT), quantify immune response via serum assays, and determine survival benefit. Stage 2 will involve administration of a fixed dose of MO32 derived from Stage 1 data followed by 4 weeks of daily Indoximod administration at a pre-determined dose, with interval comparative immune assays, neurological monitoring, and imaging surveillance. Indoximod is expected to blunt suppressive cellular (Tregs, MDSCs) immune response components, allowing a longer time for effective anti-viral responses and via cross-epitope spreading, an anti-tumor response that will be more durable than that observed with administration of virus alone. In all cases, tumor is collected, processed, and archived for future studies, including whole genome and RNA sequencing.

Results: Preliminary data from Stage 1 have demonstrated a median survival of 188 days among all canines following infusion of M032 HSV (95% confidence interval of 83.2 to 292.8 days). Nine canines have died and eight are still alive following treatment. Current dose is 1 x 109 plaque-forming units. No dose limiting toxicities have been observed with infusion of M032 alone.

Conclusions: The ability to compare human and dog responses in real time affords the most stringent test of suitability of the dog as a valid and informative model of human brain tumors. The results of this and subsequent studies will allow canine trials to properly inform the design of human trials and further support bi-translational studies and the One Medicine approach to clinical research and application.

Citation Format: M. R. Chambers, R. T. Bentley, David Crossman, Jeremy B. Foote, J. W. Koehler, James M. Markert, Simon R. Platt, Nidal B. Omar, D. M. Self, Andy Shores, Don Sorjonen, Alicia M. Waters, Amy B. Yanke, G Y. Gillespie. The One Health Consortium and combination immunotherapy: evaluating M032, a genetically engineered HSV-1 expressing Il-12, in combination with a checkpoint inhibitor in canine glioma patients [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4568.

Abstract 551: Distinct Transcriptional Roles for Wildtype vs. Truncated Nrf2 in the Heart of Transgenic Mice

Background: Nuclear erythroid-2 like factor-2 (Nrf2), a redox-sensitive transcriptional regulator of cytoprotective and antioxidant genes. Despite the basal transcription of antioxidants/redox genes, forced activation of Nrf2 may lead to “reductive stress” (RS). In this study, we hypothesized that controlled vs. sustained activation of Nrf2 differentially regulates the myocardial transcriptome, which elucidates the transition of a physiological adaptation to pathological process.

Methods: Cardiac specific Nrf2 transgenic mice expressing full length Nrf2 (FL-TG) and truncated Nrf2 (TR-TG), and their non-transgenic littermates (NTG) in the C57/BL6J backround at the age of 6-8 months were used for this study. Next generation RNA sequencing was performed using the myocardial mRNA obtained from FL-TG, TR-TG and NTG mice (n=3/group). Validation of the NGS data was carried out by qPCR analysis using specific primers for the targeted genes(n=4 to 6/group).

Results: Analysis of the NGS data uncovered eccentric genomic profiles in the myocardium of mice with a 310 differentially regulated genes (DEGs) in FL-TG ( vs. NTG) and 472 DEGs in TR-TG ( vs. NTG). A closer evaluation reveals 397 and 237 DEGs commonly shared between FL-TG and TR-TG, respectively. STRING analysis revealed genomic networks involve in oxidoreductase, antioxidant and glutathione transferase were differentially altered between TL-TG vs. TR-TG groups. For instance, within the glutathione synthesis pathway, Gclm transcript was upregulated 6.0 fold (FL-TG) and 8.0 fold (TR-TG) when compared to NTG. Indeed, a significant douwnregulation of stress response genes Hspa1b (5.0 & 2.0 fold) and Hsph1 (2.0 & 2.2 fold) was apparent in between the groups. An eccentric cytoskeletal disarrangement ( Efnb3, Map1a, Acta ), an impaired protein quality control ( Bin1,Myl4 ) and a reduced cardiac function ( Timp4) were significantly downregulated in both the groups.

Conclusion: These findings conclude that transgenic expression of wild-type vs. mutant forms of Nrf2 in the heart uniquely regulate the myocardial transcriptome, which might result in independent pathological processes.

P0046ZHX2 DOWNREGULATION DUE INSERTIONS AND DELETIONS IN THE HAS2-ZHX2 INTERGENIC REGION PREDISPOSE TO PODOCYTE DISEASE RELAPSE

Background and Aims

ZHX2 transcriptional factor is normally found in podocyte membrane forming complexes with ZHX1 and APA or ZHX3 and Ephrin B1. Altered ZHX2 expression disrupts these interactions and is related with the worsening of different primary glomerular diseases such as focal segmental glomerulosclerosis (FSGS) and minimal change disease (MCD).

A small percentage of Hodgkin lymphoma (HL) patients develop nephrotic syndrome (NS). Studies of Reed-Sternberg cell line L-1236 reveals a chromosomal rearrangement that leads to ZHX2 downregulation suggesting a possible role of ZHX2 in the development of NS in these patients.

Human podocyte disease relapse is common after a common cold probably mediated by cytokines released by immune cells and the rhinovirus.

Our aim is to study how the presence of insertions and deletions (InDels) between HAS2 and ZHX2 in patients with MCD, FSGS and HL could alter ZHX2 expression and the implication in podocyte disease relapse after a common cold and in HL.

Method

Genomic DNA between HAS2 and ZHX2 (Chr8:122624000-124001000 from UCSC hg19 GRCh37) was sequenced from 28 NS patients and 27 controls using Agilent Custom capture and high throughput Illumina sequencing. The CLC Genomics software was used to identify InDels (3-20 bp) present exclusively in patients. One of the identified InDels was replicated in human podocytes using CRISPR Cas9 and homology directed repair technology to study changes in ZHX2.

A common cold cytokine cocktail containing IL-2, IL-4R, IL-6, IL-10, INF-γ, TNF-α and ICAM-1 was injected into control (BALB/c, n=5) and ZHX2 deficient mice (BALB/cJ, n=5) (Dose X); podocyte specific ZHX2 deficient (ZHX2 flox/flox cre+/+, n=3) and floxed control mice (ZHX2 flox/flox, n=3) (dose X/15). Buffalo Mna (B. Mna) rats were also injected with the cytokine cocktail (X/50) to study relapse in FSGS (n=7).

Cell supernatant from HL Reed Sternberg cells (L-1236) (200µg of total protein) was injected into BALB/c (n=5) and BALB/cJ mice (n=5) and kidney function was assessed.

Results

Multiple InDels were found exclusively in the patient population, two of them, shared by two or more patients.

The insertion at 122,533,694 was presented in patients with MCD, FSGS and HL with NS and also in L-1236 cells. This insertion was replicated in human podocytes using CRISPR/Cas9 (CRISPR B). Another insertion noted both in patients and controls was generated for comparison (CRISPR A). A reduced ZHX2 expression was detected in CRISPR B but not in CRISPR A single cell clones.

The shared insertion at 122,787,088 was presented within the ZHX2 gene intron 1. BALB/cJ mice has lower ZHX2 expression in liver and podocytes due to an insertion in intron 1.

To study whether this insertion could be related with relapse of MCD and FSGS following a common cold, a cytokine cocktail was injected into BALB/cJ and BALB/c mice. BALB/cJ mice developed acute albuminuria after cytokine treatment (65.3±24.3 μg per 18h), but not control BALB/c mice (10.8±1.5 μg per 18h), when compared with baseline values (BALB/cJ 5.1±1.1 μg per 18h; BALB/c 6.5±1.1 μg per 18h) (p<0.05). BALB/cJ mice had also higher nuclear expression of ZHX1.

The cytokine cocktail also induced albuminuria in ZHX2 flox/flox/cre+/+ mice but not in control ZHX2 flox/flox, suggesting that ZHX2 deficiency in podocytes is responsible of kidney injury after cytokine injection.

To study common cold related relapse in FSGS, B. Mna rats were injected with a rat cytokine cocktail, showing a significant increase in proteinuria (61.5±4.2 mg per 18h) compared with baseline (47±4.1 mg per 18h).

Cell culture supernatant from L-1236 was injected into BALB/cJ and BALB/c mice to study the effect of secreted soluble mediators in NS. L-1236 supernatant (200 µg) had a nephrogenic effect in ZHX2 deficient mice but not in controls.

Conclusion

InDels between HAS2 and ZHX2 genes presented in patients with MCD, FSGS and HL, alter ZHX2 expression and are related to relapse following a common cold and in HL.

Transcriptomic Profiling of DAF-7/TGFβ Pathway Mutants in C. elegans

The transforming growth factor beta superfamily encompasses a large family of ligands that are well conserved across many organisms. They are regulators of a number of physiological and pathological processes. The model nematode Caenorhabditis elegans has been instrumental in identifying key components of the transforming growth factor beta (TGFβ) pathway. In C. elegans, the TGFβ homolog DAF-7 signals through the DAF-1 Type I and DAF-4 Type II receptors to phosphorylate downstream R-SMADs DAF-8 and DAF-14. These R-SMADs translocate into the nucleus to inhibit Co-SMAD DAF-3. Many of the roles of the canonical DAF-7 pathway, involving both DAF-1 and DAF-3, have been identified using targeted genetic studies. Few have assessed the global transcriptomic changes in response to these genes, especially in adult animals. In this study, we performed RNA sequencing on wild type, daf-1, and daf-1; daf-3 adult hermaphrodites. To assess the overall trends of the data, we identified differentially expressed genes (DEGs) and performed gene ontology analysis to identify the types of downstream genes that are differentially expressed. Hierarchical clustering showed that the daf-1; daf-3 double mutants are transcriptionally more similar to wild type than daf-1 mutants. Analysis of the DEGs showed a disproportionally high number of genes whose expression is increased in daf-1 mutants, suggesting that DAF-1 acts as a general repressor of gene expression in wild type animals. Gene ontology analysis of the DEGs produced many significantly enriched terms, including Molting Cycle, Response to Topologically Incorrect Protein, and Response to Biotic Stimulus. Understanding the direct and indirect targets of the DAF-7 TGFβ pathway through this RNA-seq dataset can provide insight into novel roles of the multifunctional signaling pathway, as well as identify novel genes that may participate in previously reported functions of TGFβ signaling.

Irbesartan in Marfan syndrome (AIMS): a double-blind, placebo-controlled randomised trial

BACKGROUND

Irbesartan, a long acting selective angiotensin-1 receptor inhibitor, in Marfan syndrome might reduce aortic dilatation, which is associated with dissection and rupture. We aimed to determine the effects of irbesartan on the rate of aortic dilatation in children and adults with Marfan syndrome.

METHODS

We did a placebo-controlled, double-blind randomised trial at 22 centres in the UK. Individuals aged 6-40 years with clinically confirmed Marfan syndrome were eligible for inclusion. Study participants were all given 75 mg open label irbesartan once daily, then randomly assigned to 150 mg of irbesartan (increased to 300 mg as tolerated) or matching placebo. Aortic diameter was measured by echocardiography at baseline and then annually. All images were analysed by a core laboratory blinded to treatment allocation. The primary endpoint was the rate of aortic root dilatation. This trial is registered with ISRCTN, number ISRCTN90011794.

FINDINGS

Between March 14, 2012, and May 1, 2015, 192 participants were recruited and randomly assigned to irbesartan (n=104) or placebo (n=88), and all were followed for up to 5 years. Median age at recruitment was 18 years (IQR 12-28), 99 (52%) were female, mean blood pressure was 110/65 mm Hg (SDs 16 and 12), and 108 (56%) were taking β blockers. Mean baseline aortic root diameter was 34·4 mm in the irbesartan group (SD 5·8) and placebo group (5·5). The mean rate of aortic root dilatation was 0·53 mm per year (95% CI 0·39 to 0·67) in the irbesartan group compared with 0·74 mm per year (0·60 to 0·89) in the placebo group, with a difference in means of -0·22 mm per year (-0·41 to -0·02, p=0·030). The rate of change in aortic Z score was also reduced by irbesartan (difference in means -0·10 per year, 95% CI -0·19 to -0·01, p=0·035). Irbesartan was well tolerated with no observed differences in rates of serious adverse events.

INTERPRETATION

Irbesartan is associated with a reduction in the rate of aortic dilatation in children and young adults with Marfan syndrome and could reduce the incidence of aortic complications.

FUNDING

British Heart Foundation, the UK Marfan Trust, the UK Marfan Association.

TMIC-12. TUMOR EDGE-DESTINED CELLS IN GBM CELLS IN A CELL-INTRINSIC MECHANISM

The highly infiltrative nature of glioblastoma (GBM) underscores limited response to current therapies and subsequent unfavorable clinical outcome. Despite the gross total resection of tumors located in the enhancing lesions, GBMs inevitably recur from the areas adjacent to the resection cavity that retains tumor cells with tumor-initiating capacity with therapy resistant nature (glioma-initiating cells: GICs). Here, we identified, in clinical GBM tumors, two mutually-exclusive glioma-initiating cell subpopulations in two different regions of GBM tumors, core- and edge-located glioma-initiating cells that co-exist in single tumors (Minata et al. Cell Reports. 2019). Following this observation, we further established patient-derived GBM clones from both tumor core and edge tissues, termed core-GICs and edge-GICs, and uncovered their distinct molecular signatures. Unexpectedly, we found that these two distinct GIC subpopulations retain the spatial identity, meaning that the core GICs locate themselves in the injected site, whereas the edge GICs initiated to form edge-like lesions, when xenografted into mouse brains. Through OMICs analyses, we identified CD38 as a key molecule to determine the edge phenotype both in vitro and in vivo. Collectively, our findings indicate, for the first time, that GBM cells are heterogeneous to be composed of tumor cells destined to be located in distinct regions of the tumors in a molecularly-defined manner.

TMOD-19. ELUCIDATING THE RESISTANCE TO IMMUNOTHERAPY IN BRAIN TUMORS USING A HUMANIZED MICROBIOME MOUSE MODEL

Although the immunotherapy anti-PD-1 works well in glioblastoma (GBM) pre-clinical mouse models, the therapy has not demonstrated a similar efficacy in patient clinical trials. Recent studies have linked the gut microbe composition to tumor growth and response to immunotherapy in some cancers. To date, all GBM pre-clinical studies have been done in mouse models using mouse gut microbiomes. There are significant differences between mouse and human microbial gut compositions, with up to 85% of gut bacteria found in laboratory mice not found in humans. Because it is known that the gut microbe composition can impact the immune system, we hypothesize that the non-responsiveness of GBM patients to immunotherapy may be due to the composition of the gut microbiome. Therefore, we have generated a humanized microbiome mouse model in which mice have been colonized by human donor microbes in their GI tract (two different healthy human donors (HuM1 and HuM2)). In preliminary results, we have found that HuM1 mice are resistant to anti-PD-1, while HuM2 mice are responders to anti-PD-1 in the GL261 syngeneic intracranial model. These mice are genetically identical and only differ in gut microbiome composition. Furthermore, we found that HuM2 mice exhibited a significant increase in cytotoxic CD8+T-cells producing IFN-γ and significant increased CD8+/Treg ratio in the spleen following anti-PD-1 treatment, which was not observed in the HuM1 mice. When testing the efficacy of standard of care temozolomide (TMZ) in our humanized mice, we found that TMZ significantly prolonged survival of both HuM1 and HuM2 mice with intracranial tumors. However, HuM2 mice exhibited superior efficacy (p< 0.001; 57% survival), compared to HuM1 mice (p< 0.01; 0% survival). We are extending these studies to analyze additional humanized microbiome lines as well as GBM patient donor lines to more accurately understand individual responses to tumor growth and responsiveness to therapies.

KSRP modulates melanoma growth and efficacy of vemurafenib

The majority of melanomas carry an oncogenic BRAF mutation (BRAF^V600E), which results in constitutive kinase activity driving melanoma proliferation. While inhibitors of BRAF^V600E (BRAFi) effectively lead to rapid tumor shrinkage, most patients treated with BRAFi develop acquired resistance. Identification of factors as regulators of melanoma growth and as potential sources of resistance is thus crucial for the design of improved therapies to treat advanced melanoma with more durable responses. Here, we show that KH-type splicing regulatory protein (KSRP) is critical for proliferation of melanoma cells without and with acquired resistance to vemurafenib. Silencing KSRP reduces cell proliferation and augments the growth suppressive effects of vemurafenib. We identify killin (KLLN), a p53-regulated DNA replication inhibitor, as a downstream effector of growth inhibition by KSRP silencing and demonstrate that KSRP promotes decay of KLLN mRNA through an RNA-protein interaction. Using heterologous mRNA reporters, we show that a U-rich element within the 3' untranslated region of KLLN is responsible for KSRP-dependent mRNA decay. These findings implicate that KSRP is an important regulator of melanoma cell growth in part through controlling KLLN mRNA stability.

Abstract 234: Nrf2-Dependent Transcriptional and Post-Transcriptional Regulatory Responses in Reductive Stress Myocardium

Background: Transient activation of nuclear factor, erythroid 2 like 2 (Nfe2l2/Nrf2), a master regulator of antioxidant transcription, protects from oxidative insult. However, sustained Nrf2 signaling causes proteotoxic reductive stress (RS). Using Nrf2 - / - mice, we recently uncovered several cardiac microRNAs (miRNAs) potentially expressed in an Nrf2-dependent manner. Here, we utilized cardiac-specific constitutively active Nrf2 transgenic (caNrf2-Tg) mice to elucidate necessary and sufficient miRNAs, and hypothesized that miRNA dysregulation underlies RS.

Methods: Next-generation RNA sequencing (RNAseq) was used to compare mRNA and miRNA transcriptomes of 6-month low (TgL) and high (TgH) transgene-expressing caNrf2-Tg mice to non-transgenic (NTg) controls (n=3-4/group). Differentially expressed genes (DEGs) were run through Ingenuity Pathway Analysis (IPA). Real-time qPCR validated RNAseq results (n=4-6/group). In silico target prediction correlated miRNA changes with corresponding mRNA levels.

Results: Principal component and hierarchal clustering analyses revealed distinct TgL and TgH transcriptomes. Relative to NTg, TgL mice exhibited 246 DEGs, 214 of which were consistent in TgH hearts. Strikingly, TgH mice displayed 1031 DEGs. As expected, IPA of DEGs indicated enhanced free radical scavenging; however, caNrf2 expression also dose-dependently enriched hypertrophic signaling, protein ubiquitination and the unfolded protein response. While 16 miRNAs were significantly altered in TgL hearts, a total of 101 miRNAs were detected TgH mice, several of which were predicted to account for mRNA changes in RS pathways. Notably, miR-671-3p and miR-455-5p, two miRNAs decreased in Nrf2 - / - mice, were reciprocally increased in caNrf2-Tg mice suggesting that Nrf2 is necessary and sufficient for their function in the heart.

Conclusion: While RS underlies human mutant protein aggregation cardiomyopathy, molecular determinants of pathogenesis downstream of Nrf2 remain unknown. Here, we identified key transcriptional responses and pathways associated with RS. These results link post-transcriptional regulation with redox imbalances in the heart, and highlight novel miRNAs for future mechanistic studies.

Abstract 5482: L-2HG/ L2HGDH axis as therapeutic target for kidney cancer

Background: The D-enantiomer of 2-hydroxygultarate (D-2HG), along with fumarate and succinate, are considered oncometabolites that promote tumorigenesis. Our lab has reported elevated levels of the L-enantiomer of 2-hydroxyglutare (L-2HG) in clear cell renal cell carcinoma (ccRCC), in part due to reduced expression of the enzyme L-2HG dehydrogenase (L2HGDH).

Objectives: Here we evaluated the underlying biochemical mechanisms of L-2HG accumulation and characterized the contribution of the L-2HG/L2HGDH axis to tumorigenesis.

Experimental strategy: We assessed the role of raised L-2HG in renal carcinogenesis via both in vitro and in vivo means. Mutagenesis and knock down approaches were applied to study involvement of loss of L2HGDH in accumulation of high L-2HG levels and associated tumor phenotypes. Metabolomics coupled with 13C tracer labeling studies were utilized to dissect the biochemical axis that promotes L-2HG accumulation in RCC cells.

Results: Translational based studies demonstrate that loss of L2HGDH expression is associated with both cancer progression and worsened outcomes. In connection with our previous findings, we demonstrate that raising cellular L-2HG levels by treatment with cell permeable octyl ester of L-2HG as well as by shRNA-mediated knock down of L2HGDH in renal epithelial cells (HK-2) promotes in vitro tumor phenotypes. Concurrently, the epigenetic mark 5hmc was significantly decreased under high L-2HG levels. Further investigation with restoration of L2HGDH in RCC cells (RXF393 and A498) shows decreased L-2HG levels and suppression of in vivo tumor growth in nude mice (NU/NU). Interestingly, expression of loss-of-function mutant of L2HGDH was unable to decrease L-2HG levels and failed to suppress in vitro and in vivo tumor phenotypes. In addition, high L-2HG levels were found to upregulate epithelial-mesenchymal-transition (EMT) marker SNAIL1 and correspondingly downregulate E-cadherin. Biochemical studies demonstrate that the predominant carbon source for L-2HG in RCC is glutamine through the activity of glutaminase and malate dehydrogenase (MDH). Pharmacological inhibition of the glutamine/MDH axis by treatment of glutaminase inhibitor (CB-839) and MDH inhibitor (4k) in RCC cells reduced L-2HG levels and mitigates in vitro tumor phenotypes. Furthermore, suppression of in vitro phenotypes by CB-839 and shRNA-mediated MDH2 knockdown was rescued by concurrent treatment with octyl ester of L-2HG. Finally, restoration of L2HGDH promoted the expression of genes targeted by the polycomb repressor complex 2 (PRC2), whereas inhibition of PRC2 in high L-2HG cells suppressed tumor phenotypes.

Conclusion: Collectively, our data demonstrate the biologic relevance of high L-2HG to renal carcinogenesis and reveal novel therapeutic opportunities for L-2HG driven kidney tumors.

Citation Format: Sandeep Balu Shelar, Eun-hee Shim, Garrett Brinkley, Anirban Kundu, Hyeyoung Nam, Francesca Carobbio, Tyler Poston, Jubilee Tan, Daniel Benson, Dinesh Rakheja, Richard Kirkman, Yusuke Sato, Seishi Ogawa, Shilpa Dutta, Sadanandan E. Velu, David Crossman, Anja Becker, Conrad Kunick, Sunil Sudarshan. L-2HG/ L2HGDH axis as therapeutic target for kidney cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5482.

Dietary Docosahexaenoic Acid Reduces Oscillatory Wall Shear Stress, Atherosclerosis, and Hypertension, Most Likely Mediated via an IL-1-Mediated Mechanism

BACKGROUND

Hypertension is a complex condition and a common cardiovascular risk factor. Dietary docosahexaenoic acid (DHA) modulates atherosclerosis and hypertension, possibly via an inflammatory mechanism. IL-1 (interleukin 1) has an established role in atherosclerosis and inflammation, although whether IL-1 inhibition modulates blood pressure is unclear.

METHODS AND RESULTS

Male apoE-/- (apolipoprotein E-null) mice were fed either a high fat diet or a high fat diet plus DHA (300 mg/kg per day) for 12 weeks. Blood pressure and cardiac function were assessed, and effects of DHA on wall shear stress and atherosclerosis were determined. DHA supplementation improved left ventricular function, reduced wall shear stress and oscillatory shear at ostia in the descending aorta, and significantly lowered blood pressure compared with controls (119.5±7 versus 159.7±3 mm Hg, P<0.001, n=4 per group). Analysis of atheroma following DHA feeding in mice demonstrated a 4-fold reduction in lesion burden in distal aortas and in brachiocephalic arteries (P<0.001, n=12 per group). In addition, DHA treatment selectively decreased plaque endothelial IL-1β (P<0.01).

CONCLUSIONS

Our findings revealed that raised blood pressure can be reduced by inhibiting IL-1 indirectly by administration of DHA in the diet through a mechanism that involves a reduction in wall shear stress and local expression of the proinflammatory cytokine IL-1β.

Antiretroviral therapy potentiates high-fat diet induced obesity and glucose intolerance

Objective

Breakthroughs in HIV treatment, especially combination antiretroviral therapy (ART), have massively reduced AIDS-associated mortality. However, ART administration amplifies the risk of non-AIDS defining illnesses including obesity, diabetes, and cardiovascular disease, collectively known as metabolic syndrome. Initial reports suggest that ART-associated risk of metabolic syndrome correlates with socioeconomic status, a multifaceted finding that encompasses income, race, education, and diet. Therefore, determination of causal relationships is extremely challenging due to the complex interplay between viral infection, ART, and the many environmental factors.

Methods

In the current study, we employed a mouse model to specifically examine interactions between ART and diet that impacts energy balance and glucose metabolism. Previous studies have shown that high-fat feeding induces persistent low-grade systemic and adipose tissue inflammation contributing to insulin resistance and metabolic dysregulation via adipose-infiltrating macrophages. Studies herein test the hypothesis that ART potentiates the inflammatory effects of a high-fat diet (HFD). C57Bl/6J mice on a HFD or standard chow containing ART or vehicle, were subjected to functional metabolic testing, RNA-sequencing of epididymal white adipose tissue (eWAT), and array-based kinomic analysis of eWAT-infiltrating macrophages.

Results

ART-treated mice on a HFD displayed increased fat mass accumulation, impaired glucose tolerance, and potentiated insulin resistance. Gene set enrichment and kinomic array analyses revealed a pro-inflammatory transcriptional signature depicting granulocyte migration and activation.

Conclusion

The current study reveals a HFD-ART interaction that increases inflammatory transcriptional pathways and impairs glucose metabolism, energy balance, and metabolic dysfunction.

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Antiretroviral therapy (ART) exacerbates high-fat diet induced obesity and dysregulation of glucose homeostasis.

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Transcriptomic and Kinomic analyses identify increased pro-inflammatory, adipose-tissue macrophages after ART-treatment.

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ART and high-fat diet synergistically induce the G-protein coupled receptor, Gpr50, in white adipose tissue.

ATP Evokes Ca2+ Responses and CXCL5 Secretion via P2X4 Receptor Activation in Human Monocyte-Derived Macrophages

Leukocytes sense extracellular ATP, a danger-associated molecular pattern, released during cellular stress and death, via activation of cell surface P2X and P2Y receptors. Here, we investigate P2 receptor expression in primary human monocyte-derived macrophages and receptors that mediate ATP-evoked intracellular [Ca²⁺]_i signals and cytokine production in response to ATP concentrations that exclude P2X₇ receptor activation. Expression of P2X₁, P2X₄, P2X₅, P2X₇, P2Y₁, P2Y₂, P2Y₄, P2Y₆, P2Y₁₁, and P2Y₁₃ was confirmed by quantitative RT-PCR and immunocytochemistry. ATP elicited intracellular Ca²⁺ responses in a concentration-dependent fashion (EC₅₀ = 11.4 ± 2.9 μM, n = 3). P2Y₁₁ and P2Y₁₃ activations mediated the amplitude of [Ca²⁺]_i response, whereas P2X₄ activation, but not P2X₁ or P2X₇, determined the duration of Ca²⁺ response during a sustained phase. ATP mediated gene induction of CXCL5, a proinflammatory chemokine. P2X₄ antagonism (PSB-12062 or BX430) inhibited ATP-mediated induction of CXCL5 gene expression and secretion of CXCL5 by primary macrophage. Inhibition of CXCL5 secretion by P2X₄ antagonists was lost in the absence of extracellular Ca²⁺ Reciprocally, positive allosteric modulation of P2X₄ (ivermectin) augmented ATP-mediated CXCL5 secretion. P2X₇, P2Y₁₁, or P2Y₁₃ receptor did not contribute to CXCL5 secretion. Together, the data reveals a role for P2X₄ in determining the duration of ATP-evoked Ca²⁺ responses and CXCL5 secretion in human primary macrophage.

Identification of transcriptome signature for myocardial reductive stress

The nuclear factor erythroid 2 like 2 (Nfe2l2/Nrf2) is a master regulator of antioxidant gene transcription. We recently identified that constitutive activation of Nrf2 (CaNrf2) caused reductive stress (RS) in the myocardium. Here we investigate how chronic Nrf2 activation alters myocardial mRNA transcriptome in the hearts of CaNrf2 transgenic (TG-low and TG-high) mice using an unbiased integrated systems approach and next generation RNA sequencing followed by qRT-PCR methods. A total of 246 and 1031 differentially expressed genes (DEGs) were identified in the heart of TGL and TGH in relation to NTG littermates at ~ 6 months of age. Notably, the expression and validation of the transcripts were gene-dosage dependent and statistically significant. Ingenuity Pathway Analysis identified enriched biological processes and canonical pathways associated with myocardial RS in the CaNrf2-TG mice. In addition, an overrepresentation of xenobiotic metabolic signaling, glutathione-mediated detoxification, unfolded protein response, and protein ubiquitination was observed. Other, non-canonical signaling pathways identified include: eNOS, integrin-linked kinase, glucocorticoid receptor, PI3/AKT, actin cytoskeleton, cardiac hypertrophy, and the endoplasmic reticulum stress response. In conclusion, this mRNA profiling identified a "biosignature" for pro-reductive (TGL) and reductive stress (TGH) that can predict the onset, rate of progression, and clinical outcome of Nrf2-dependent myocardial complications. We anticipate that this global sequencing analysis will illuminate the undesirable effect of chronic Nrf2 signaling leading to RS-mediated pathogenesis besides providing important guidance for the application of Nrf2 activation-based cytoprotective strategies.

Whole-exome sequencing (WES) of penile squamous cell carcinoma (PSCC) to identify multiple recurrent mutations

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Background: Molecular alterations and drivers of PSCC, an orphan malignancy, remain unclear. The Cancer Genome Atlas is not studying PSCC and the Catalogue of Somatic Mutations in Cancer has performed targeted analyses only. We report WES of PSCC tumors from a group of patients (pts). Methods: Freshfrozen macrodissected PSCC tumor tissue and adjacent normal tissue samples were procured from the Cooperative Human Tissue Network. DNA was isolated from tissue sections by phenol chloroform extraction. Exome capture was performed with the Agilent SureSelect clinical research exome kit and whole exome-seq was done on the Illumina HiSeq2500 with paired end 100bp chemistry. Raw sequence data in Fastq format were aligned to human reference genome and quantified, and compared by using a local instance of Galaxy (galaxy.uabgrid.uab.edu). These data were analyzed for mutations (SNPs) analysis, by Partek Genomic Suite/Flow(PGS, Partek, St. Louis, MO) for variance calling against human reference genome (hg19) as referenced to dbSNP; and copy number variants (cnv) by FishingCNV tool together with picard tools/samtools/GATK). We focused on missense mutations and amplifications among ≥ 2 tumor samples but not in normal samples as they may cause upregulation of gene/protein function, which may be therapeutically actionable. Results: PSCC tumors were available from 11 patients and adjacent normal tissue from 3 patients. The 10 most common genes with > 4 missense mutations among ≥ 2 tumor samples overall were the following in decreasing order of frequency: MUC4, HLA-DPA1, MUC16, XIRP2, SSPO, TTN, FCGBP, PABPC3, ALPK2 and MKI67. The top upstream transcriptional regulators were PIH1D3, PRDM5, PTK2, Coup-Tf and NBEAL2. When examining candidate actionable genes, recurrent missense alterations were seen in PIK3C2A and PIK3C2G. Additional analysis will study alterations in functional domains and cnv. Conclusions: WES identified a relatively high mutation burden in PSCC withrecurrent missense mutations in multiple genes, notably including the PI3K gene among potentially actionable genes. Validation of these findings and further study of downstream effects is required.

Integrated comprehensive high-throughput kinomics profiling and whole exome sequencing of penile squamous cell cancer (PSCC)

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Background: Molecular drivers in penile squamous cell cancer (PSCC), an orphan malignancy, remain unclear. The Cancer Genome Atlas (TCGA) is not studying PSCC and the Catalogue of Somatic Mutations in Cancer (COSMIC) investigators have reported only targeted analyses of PSCC. We report the first integrated analyses of comprehensive kinomics and whole exome sequencing (seq) in tumors from patients (pts) with PSCC . Methods: We performed integrated functional kinomics profiling and comprehensive exome-seq of two frozen tissue samples from men with PSCC with a matched normal tissue procured from the Cooperative Human Tissue Network (CHTN). Kinomic profiling was performed using the PamStation 12 high-content phospho-peptide substrate microarray system (PamGene International). The protein tyrosine kinome and serine/threonine kinome PamChips were used to measure global kinase activity by detecting phosphorylation of various peptides through FITC-labeled antibodies. Upstream kinase prediction was performed using a scoring algorithm that incorporates the phosphonet database (www.phosphonet.ca). Exome capture was performed with the Agilent SureSelect v5 kit and whole exome-seq was done on the Illumina HiSeq2000 with paired end 100bp chemistry. Results: In the single patient, paired kinomics analysis comparing the tumor sample to adjacent normal tissue, the HER family (EGFR, ERBB2, 3 and 4), AXL, TYRO3 and SYK kinases were the most active. When combining the two tumors in an unpaired analysis against the normal sample, the HER (EGFR, ERBB2, 3 and 4), MER, FRK, and FAK, kinases showed increased activity. When comparing whole exome-seq of the two PSCC samples with normal, among the affected genes were CCDC181, ZNF717, MUC4, HGC6.3, NOTCH1, STK11, SIRPB1, SKA3, PDE6B, FAT1, CACNA2D1, USP17L11, MNT, and CEP89. We are evaluating 10 PSCC tumors and matched normal tissue by kinomics and whole exome-seq and will present these complete data and analysis at the conference. Conclusions: In our preliminary analysis of pts that underwent the first reported integrated kinomics and whole exome-seq performed in PSCC, we identified multiple potential therapeutic targets in tumors.

Phenotypic analysis of B cell subsets in HLA*B44 positive identical twins discordant for common variable immunodeficiency and recurrent sino-pulmonary infection (P3331)

Depressed serum immunoglobulin levels (sIgs) and recurrent sinopulmonary infections mark Common Variable Immune Deficiency (CVID). Many family members of CVID patients also suffer recurrent sinopulmonary infection (RESPI) but have normal sIg. We identified HLAB44 positive identical female twins who suffer sinopulmonary infections and are discordant for CVID and RESPI. Flow cytometry subsets showed equivalent numbers of immature B cells (BC) in both twins, but lower numbers of transitional and mature BC in the CVID twin. Deep sequencing of the immunoglobulin (Ig) repertoires expressed by the transitional and mature BC showed a significant divergence in the utilization of VH1 and VH4 family gene segments, with CVID favoring VH4 and RESPI VH1. RESPI twin used JH6 more frequently, whereas CVID twin used JH3. The amino acid composition of CDR-H3 repertoire was compared with a control; the twin and control tyrosine usage in transitional BC was similar (~15%) but greatly diverged in mature BC (control 15%, RESPI 25%, CVID &lt; 10%). Whole genome sequencing revealed homozygosity for a rare CD21 S639N polymorphism and heterozygosity for CD19 L174V. These findings suggest that in addition to an acquired block in BC development at the transitional stage, the CVID twin produces an Ig repertoire that is markedly depleted of tyrosine. This may explain why the function of the Ig repertoire in CVID is more impaired than what might be expected by sIgs levels.

Interleukin-1 mediates neuroinflammatory changes associated with diet-induced atherosclerosis

BACKGROUND

Systemic inflammation contributes to brain pathology in cerebrovascular disease through mechanisms that are poorly understood.

METHODS AND RESULTS

Here we show that atherosclerosis, a major systemic inflammatory disease, is associated with severe cerebrovascular inflammation in mice and that this effect is mediated by the proinflammatory cytokine interleukin-1 (IL-1). Apolipoprotein E-deficient mice fed Paigen or Western diets develop vascular inflammation, microglial activation, and leukocyte recruitment in the brain, which are absent in apolipoprotein E-deficient mice crossed with IL-1 type 1 receptor-deficient mice. Systemic neutralization of IL-1β with an anti-IL-1β antibody reversed aortic plaque formation (by 34% after a Paigen and 45% after a Western diet) and reduced inflammatory cytokine expression in peripheral organs. Central, lipid accumulation-associated leukocyte infiltration into the choroid plexus was reversed by IL-1β antibody administration. Animals fed a Western diet showed 57% lower vascular inflammation in the brain than that of mice fed a Paigen diet, and this was reduced further by 24% after IL-1β antibody administration.

CONCLUSIONS

These results indicate that IL-1 is a key driver of systemically mediated cerebrovascular inflammation and that interventions against IL-1β could be therapeutically useful in atherosclerosis, dementia, or stroke. (J Am Heart Assoc. 2012;1:e002006 doi: 10.1161/JAHA.112.002006.).

Dietary Phosphate Modulates Atherogenesis and Insulin Resistance in Apolipoprotein E Knockout Mice—Brief Report

Objective—

Epidemiological studies link higher serum phosphate and the phosphatonin fibroblast growth factor 23 with cardiovascular events and atheroma, and they link lower serum phosphate with insulin resistance and the metabolic syndrome. We investigated whether manipulating dietary phosphate influences atherogenesis or insulin sensitivity in mice.

Methods and Results—

Apolipoprotein E knockout mice were fed an atherogenic diet with low (0.2%), standard (0.6%), or high (1.6%) phosphate content. Serum phosphate and fibroblast growth factor 23 significantly increased with increasing dietary phosphate intake, but lipid profile and blood pressure were unaffected. After 20 weeks, mice on the higher phosphate diet had significantly more atheroma at the aortic sinus (42±1.9% versus 30±1.5% for high versus low phosphate, P <0.01). Compared with standard and high-phosphate diet groups, mice on a low-phosphate diet had more adipose tissue and a 4-fold increase in insulin resistance measured by homeostatic model assessment (43.7±9.3 versus 8.9±0.7 for low versus high phosphate, P <0.005).

Conclusion—

A high-phosphate diet accelerates atherogenesis in apolipoprotein E −/− mice, whereas low phosphate intake induces insulin resistance. These data indicate for the first time that controlling dietary phosphate intake may influence development of both atherosclerosis and the metabolic syndrome.

Brain inflammation is induced by co-morbidities and risk factors for stroke

Chronic systemic inflammatory conditions, such as atherosclerosis, diabetes and obesity are associated with increased risk of stroke, which suggests that systemic inflammation may contribute to the development of stroke in humans. The hypothesis that systemic inflammation may induce brain pathology can be tested in animals, and this was the key objective of the present study. First, we assessed inflammatory changes in the brain in rodent models of chronic, systemic inflammation. PET imaging revealed increased microglia activation in the brain of JCR-LA (corpulent) rats, which develop atherosclerosis and obesity, compared to the control lean strain. Immunostaining against Iba1 confirmed reactive microgliosis in these animals. An atherogenic diet in apolipoprotein E knock-out (ApoE(-/-)) mice induced microglial activation in the brain parenchyma within 8 weeks and increased expression of vascular adhesion molecules. Focal lipid deposition and neuroinflammation in periventricular and cortical areas and profound recruitment of activated myeloid phagocytes, T cells and granulocytes into the choroid plexus were also observed. In a small, preliminary study, patients at risk of stroke (multiple risk factors for stroke, with chronically elevated C-reactive protein, but negative MRI for brain pathology) exhibited increased inflammation in the brain, as indicated by PET imaging. These findings show that brain inflammation occurs in animals, and tentatively in humans, harbouring risk factors for stroke associated with elevated systemic inflammation. Thus a "primed" inflammatory environment in the brain may exist in individuals at risk of stroke and this can be adequately recapitulated in appropriate co-morbid animal models.

4D super-resolution microscopy with conventional fluorophores and single wavelength excitation in optically thick cells and tissues

BACKGROUND

Optical super-resolution imaging of fluorescently stained biological samples is rapidly becoming an important tool to investigate protein distribution at the molecular scale. It is therefore important to develop practical super-resolution methods that allow capturing the full three-dimensional nature of biological systems and also can visualize multiple protein species in the same sample.

METHODOLOGY/PRINCIPAL FINDINGS

We show that the use of a combination of conventional near-infrared dyes, such as Alexa 647, Alexa 680 and Alexa 750, all excited with a 671 nm diode laser, enables 3D multi-colour super-resolution imaging of complex biological samples. Optically thick samples, including human tissue sections, cardiac rat myocytes and densely grown neuronal cultures were imaged with lateral resolutions of ∼15 nm (std. dev.) while reducing marker cross-talk to <1%. Using astigmatism an axial resolution of ∼65 nm (std. dev.) was routinely achieved. The number of marker species that can be distinguished depends on the mean photon number of single molecule events. With the typical photon yields from Alexa 680 of ∼2000 up to 5 markers may in principle be resolved with <2% crosstalk.

CONCLUSIONS/SIGNIFICANCE

Our approach is based entirely on the use of conventional, commercially available markers and requires only a single laser. It provides a very straightforward way to investigate biological samples at the nanometre scale and should help establish practical 4D super-resolution microscopy as a routine research tool in many laboratories.

TRAIL attenuates the development of atherosclerosis in apolipoprotein E deficient mice

TRAIL (tumour necrosis factor-related apoptosis inducing ligand) is most often reported to induce apoptosis in tumour cells. It is expressed in artery walls but its role and regulation in vascular pathologies is little studied. We aimed to measure the effect of genetic deletion of TRAIL on atherosclerosis in a mouse model. TRAIL was mainly expressed in endothelium, smooth muscle cells and macrophages within plaques. The absence of TRAIL in chow and in fat-fed mice led to greater lesion coverage in aortae (8 weeks, % area ± SEM), n=7-8, 1.24 ± 0.2 (no TRAIL, chow diet) vs. 0.42 ± 0.1, p<0.01 and 3.4 ± 0.8 (no TRAIL, Western diet) vs. 0.94 ± 0.2, p<0.01 and larger, smooth muscle cell rich lesions at aortic roots than control mice (8 weeks, mean lesion area/total cross sectional area ± SEM, n=7-8, 0.17 ± 0.01 (no TRAIL, chow diet) vs. 0.135 ± 0.006, p<0.05 and 0.36 ± 0.03 (no TRAIL, Western diet) vs. 0.23 ± 0.02, p<0.05) particularly at early time points. The larger early lesions appeared to be as a result of increased smooth muscle cells in lesions of TRAIL deficient, pro-atherosclerotic animals. We conclude that TRAIL attenuates plaque size at early stages of atherosclerosis.