Rapid quantitative detection system for measles virus-neutralizing antibodies using HiBiT-tagged virus-like particles

Immunological testing to detect neutralizing antibodies (NAbs) is important in measles (MV) infection control. Currently, the plaque reduction neutralization test is the only credible method for measuring actual virus NAbs; however, its feasibility is hampered by drawbacks, such as long turnaround times, low throughput, and the need for laboratory biosafety equipment. To solve these problems, we developed a simple and rapid MV-NAb detection system using lentivirus-based virus-like particles incorporated with the NanoLuc fragment peptide HiBiT comprising the MV fusion protein and hemagglutinin on their exterior surface. Overall, this simple, safe, and rapid method could be used to detect MV NAbs.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Integrated tandem affinity protein purification using the polyhistidine plus extra 4 amino acids (HiP4) tag system

Peptide tag systems are a robust biophysical and biochemical method that is widely used for protein detection and purification. Here, we developed a novel tag system termed "HiP4" (histidine plus four amino acids) whose epitope sequence comprises only seven amino acids (HHHDYDI) that partially overlap with the conventional 6x histidine tag (6xHis-tag). We produced a monoclonal antibody against the HiP4 tag that can be used in multiple immunoassays with high specificity and affinity. Using this system, we developed a tandem affinity purification (TAP) and mass spectrometry (TAP-MS) system for comprehensive protein interactome analysis. The integrated use of nickel bead purification followed by HiP4 tag immunoprecipitation made it possible to reduce nonspecific binding and improve selectivity, leading to the recovery of previously unrecognized proteins that interact with hepatitis B virus X (HBx) protein or TAR DNA-binding protein 43 (TARDBP or TDP-43). Our results indicate that this system may be viable as a simple and powerful tool for TAP-MS that can achieve low background and high selectivity in comprehensive protein-protein interaction analyses.

Generation and Utilization of a Monoclonal Antibody against Hepatitis B Virus Core Protein for a Comprehensive Interactome Analysis

Hepatitis B virus (HBV) core antigen (HBc) is a structural protein that forms the viral nucleocapsid and is involved in various steps of the viral replication cycle, but its role in the pathogenesis of HBV infection is still elusive. In this study, we generated a mouse monoclonal antibody (mAb) against HBc and used it in antibody-based in situ biotinylation analysis in order to identify host proteins that interact with HBc. HBc antigen was produced with a wheat germ cell-free protein synthesis system and used to immunize mice. Among the established hybridoma clones, a single clone (mAb #7) was selected and further characterized for its ability in the antibody-based in situ biotinylation analysis to collect host proteins that are in the vicinity of HBc. Using mass spectrometry, we identified 215 HBc-interacting host proteins, three of which bind HBc most significantly under hypoxic conditions. Our results indicate that mAb #7 can be used to systematically identify host proteins that interact with HBc under pathophysiological conditions, and thus may be useful to explore the molecular pathways involved in HBV-induced cytopathogenesis.

Crosstalk between the innate immune system and selective autophagy in hepatitis B virus infection

Although the involvement of macroautophagy/autophagy in hepatitis B virus (HBV) infection has become clearer recently, whether selective autophagy plays an important role in suppressing HBV remains uncertain. We recently found that LGALS9 (galectin 9) is an interferon (IFN)-inducible protein involved in the suppression of HBV replication. Expression of LGALS9 in HBV-infected cells causes the formation of cytoplasmic puncta that degrade the HBV core protein (HBc) in conjunction with RSAD2/viperin, another IFN-inducible protein. LGALS9 binds to HBc via RSAD2 and promotes the autoubiquitination of RNF13 (ring finger protein 13) to recruit SQSTM1/p62, resulting in the formation of LC3-positive autophagosomes that degrade HBc. Both LGALS9 and RSAD2 are encoded by IFN-stimulated genes that act synergistically to induce HBc proteolysis in HBV-infected hepatocytes in an IFN-dependent manner. These results reveal a crosstalk mechanism between the innate immune system and selective autophagy during viral infection.

Galectin-9 restricts hepatitis B virus replication via p62/SQSTM1-mediated selective autophagy of viral core proteins

Autophagy has been linked to a wide range of functions, including a degradative process that defends host cells against pathogens. Although the involvement of autophagy in HBV infection has become apparent, it remains unknown whether selective autophagy plays a critical role in HBV restriction. Here, we report that a member of the galectin family, GAL9, directs the autophagic degradation of HBV HBc. BRET screening revealed that GAL9 interacts with HBc in living cells. Ectopic expression of GAL9 induces the formation of HBc-containing cytoplasmic puncta through interaction with another antiviral factor viperin, which co-localized with the autophagosome marker LC3. Mechanistically, GAL9 associates with HBc via viperin at the cytoplasmic puncta and enhanced the auto-ubiquitination of RNF13, resulting in p62 recruitment to form LC3-positive autophagosomes. Notably, both GAL9 and viperin are type I IFN-stimulated genes that act synergistically for the IFN-dependent proteolysis of HBc in HBV-infected hepatocytes. Collectively, these results reveal a previously undescribed antiviral mechanism against HBV in infected cells and a form of crosstalk between the innate immune system and selective autophagy in viral infection.

In human cells, invading pathogens trigger an innate immune response that helps prevent viral replication and spread. Here, the authors reveal a mechanism of innate immunity that selectively leads to the autophagic degradation of hepatitis B virus core protein.

Interaction of Eating Status and Dietary Variety on Incident Functional Disability among Older Japanese Adults

OBJECTIVES

To examine whether eating status and dietary variety were associated with functional disability during a 5-year follow-up analysis of older adults living in a Japanese metropolitan area.

DESIGN

A 5-year follow-up study.

SETTING

Ota City, Tokyo, Japan.

PARTICIPANTS

A total of 10,308 community-dwelling non-disabled adults aged 65-84 years.

MEASUREMENTS

Eating status was assessed using a self-reported questionnaire. Dietary variety was assessed using the dietary variety score (DVS). Based on the responses, participants were classified according to eating alone or together and DVS categories (low: 0-3; high: 4-10). Functional disability incidence was prospectively identified using the long-term care insurance system's nationally unified database. Multilevel survival analyses calculated the adjusted hazard ratio (HR) and 95% confidence interval (CI) for incident functional disability.

RESULTS

During a 5-year follow-up, 1,991 (19.3%) individuals had functional disabilities. Eating status or DVS were not independently associated with incident functional disability. However, interaction terms between eating status and DVS were associated with functional disability; HR (95% CI) for eating together and low DVS was 1.00 (0.90-1.11), eating alone and high DVS was 0.95 (0.77-1.17), and eating alone and low DVS was 1.20 (1.02-1.42), compared to those with eating together and high DVS.

CONCLUSION

Older adults should avoid eating alone or increase dietary variety to prevent functional disability. This can be ensured by providing an environment of eating together or food provision services for eating a variety of foods in the community.

Phosphopeptide enrichment using Phos-tag technology reveals functional phosphorylation of the nucleocapsid protein of SARS-CoV-2

Phosphorylation of viral proteins serves as a regulatory mechanism during the intracellular life cycle of infected viruses. There is therefore a pressing need to develop a method to efficiently purify and enrich phosphopeptides derived from viral particles in biological samples. In this study, we utilized Phos-tag technology to analyze the functional phosphorylation of the nucleocapsid protein (N protein; NP) of severe respiratory syndrome coronavirus 2 (SARS-CoV-2). Viral particles were collected from culture supernatants of SARS-CoV-2-infected VeroE6/TMPRSS2 cells by ultracentrifugation, and phosphopeptides were purified by Phos-tag magnetic beads for LC-MS/MS analysis. Analysis revealed that NP was reproducibly phosphorylated at serine 79 (Ser79). Multiple sequence alignment and phylogenetic analysis showed that the Ser79 was a distinct phospho-acceptor site in SARS-CoV-2 but not in other beta-coronaviruses. We also found that the prolyl-isomerase Pin1 bound to the phosphorylated Ser79 in NP and positively regulated the production of viral particles. These results suggest that SARS-CoV-2 may have acquired the potent virus-host interaction during its evolution mediated by viral protein phosphorylation. Moreover, Phos-tag technology can provide a useful means for analyzing the functional phosphorylation of viral proteins.

Significance

In this study, we aimed to investigate the functional phosphorylation of SARS-CoV-2 NP. For this purpose, we used Phos-tag technology to purify and enrich virus-derived phosphopeptides with high selectivity and reproducibility. This method can be particularly useful in analyzing viral phosphopeptides from cell culture supernatants that often contain high concentrations of fetal bovine serum and supplements. We newly identified an NP phosphorylation site at Ser79, which is important for Pin1 binding. Furthermore, we showed that the interaction between Pin1 and phosphorylated NP could enhance viral replication in a cell culture model.

Fertility preservation immediately after therapeutic abortion results in multiple normal follicular growth with the absence of mature oocytes due to early luteinization: a case report and literature review

Cancer therapy has priority over fertility preservation. The time available for fertility preservation in patients with cancer is often very limited and depends on the condition of the underlying disease. This case report presents the results of two rounds of controlled ovarian stimulations (COSs) performed after an induced abortion. The patient had mixed phenotype acute leukemia diagnosed during early pregnancy and underwent a surgical abortion, followed by ovarian stimulation using urinary follicle-stimulating hormone (uFSH) and gonadotropin-releasing hormone (GnRH) agonists. Oocyte retrieval was subsequently performed for oocyte cryopreservation. Despite good hormonal and ultrasonic follicular growth, no oocytes were obtained. During a second COS performed at a low human chorionic gonadotropin (hCG) level (less than 100 IU/L), several mature oocytes were obtained, suggesting that higher hCG levels during COS induce the absence of mature oocytes during normal follicular growth. It is recommended to start COS post-abortion after confirming a low hCG level while considering the timing of cancer treatment.

Correlations between pathological deposition and non-invasive diagnostic modalities like 99mTc-PYP scintigraphy, cardiac magnetic resonance, GLS in patients with transthyretin cardiac amyloidosis

Background

Although wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM) was previously considered a rare disease, recent diagnostic imaging modalities have revealed that it is considerably underdiagnosed among elderly patients with heart failure. The severity of CM is thought to be related to the extent of amyloid deposition in heart.

99mTc-labeled pyrophosphate (99mTc-PYP) scintigraphy, cardiovascular magnetic resonance (CMR), global longitudinal strain (GLS) provide diagnostic and prognostic information in ATTRwt-CM. However, the relevance of these imaging modalities and their association with cardiac amyloid load has not been fully evaluated.

Purpose

The aim of study was to elucidate the associations between pathological amyloid load and cardiac retention evaluated by 99mTc-PYP scintigraphy, CMR, GLS in patients with ATTRwt-CM.

Method

Cardiac amyloid load was calculated as (amyloid deposition area/ total myocardium area)×100 using endomyocardial biopsy specimen. Cardiac retention was quantified by heart to contralateral (H/CL) ratio by 99mTc-PYP scintigraphy. Native T1 and extracellular volume (ECV) were obtained by CMR. GLS was analyzed using the 2D echo at the time of diagnosis.

Result

The mean cardiac amyloid load was 23.0±15.2% (n=57) and correlation with H/CL ratio (1.94±0.36 n=57), native T1 (1426.7±52.5 n=57), ECV (57.9±12.9 n=54), GLS (−9.1±2.4 n=57) were positive (r=0.375 p=0.004, r=0.496 r=0.304 p&lt;0.001, r=0.304 p=0.025, r=0.473 p&lt;0.001).

Conclusion

Increased cardiac amyloid load correlated with an increased 99mTc-PYP positivity, native T1, ECV, and an impaired GLS. These results suggest that imaging parameters may reflect histological and functional changes due to amyloid deposition in the myocardium.

Funding Acknowledgement

Type of funding sources: None.

Gender differences in clinical characteristics in wild-type transthyretin amyloidosis cardiomyopathy

Aims

A significant male predominance has been reported in wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM). In other words, the female ATTRwt-CM may be overlooked and gender differences in ATTRwt-CM remain unclear. This study aims to examine gender differences in clinical characteristics and diagnostic approaches in ATTRwt-CM.

Methods and results

We retrospectively evaluated 171 consecutive ATTRwt-CM patients diagnosed at our university hospital between December 2002 and December 2020. Twenty-two patients (12%) were women. Women were significantly older at diagnosis (77.3 years vs. 83.3 years; P&lt;0.001) and had a higher advanced New York Health Association functional class (2.23±0.70 vs. 2.57±0.81; P=0.04) than men. In echocardiography, mean interventricular septum diameter was less thick (15.8 mm vs. 14.5 mm; P=0.03) and ejection fraction was preserved (51.7% vs. 57.7%; P=0.08) in women. The mean heart-to-contralateral ratio obtained using 99mTc-labeled pyrophosphate (99mTc-PYP) was significantly lower in women than in men (1.89 vs. 1.64; P=0.001). There was no significant gender difference in high-sensitivity median cardiac troponin T levels at diagnosis (0.055 ng/mL vs. 0.069 ng/mL; P=0.30) or history of carpal tunnel syndrome (57% vs. 55%; P=0.93) and electrocardiograms findings. However, the median B-type natriuretic peptide level was significantly higher (254 pg/mL vs. 434 pg/mL; P=0.02) in women. Moderate to severe aortic stenosis was more frequently observed in women (5% vs. 50%; P&lt;0.001). Histological (78% vs. 59%; P=0.07) and genetic confirmation (78% vs. 59%; P=0.003) of ATTRwt-CM were not performed in women.

Conclusion

Women with ATTRwt-CM were predominantly octogenarians, less hypertrophic, and had weaker cardiac uptake of the 99mTc-PYP tracer than men with ATTRwt-CM. These characteristics contribute to the underdiagnosis of ATTRwt-CM in women. The diagnosis of ATTRwt-CM in women is challenging. Therefore, we must be familiar with the clinical characteristics of women with ATTRwt-CM.

Funding Acknowledgement

Type of funding sources: None.

P–572 Purifying selection for aneuploidy cells in mosaicism embryo at post-implantation stage

Study question

Why low ratio mosaicism embryos develop to normal karyotype babies?

Summary answer

Our in vitro implantation assay clarified purifying selection for aneuploid cells in post implantation embryos.

What is known already

There are some reports about healthy live birth after transfer of mosaic embryos, which was reported for the first time from Italy in 2015. It is also reported that the abnormal cell is screened with the mouse in the embryo development, and only a normal cell contributes to the development. But it has not been examined in human.

Study design, size, duration

To clarify the change of aneuploid cells and mitochondrial activity in human embryo, we biopsied several parts from one blastocyst and examined karyotype. After in vitro implantation assay for biopsied embryos, we compared the karyotype of biopsy sample with that of cultured cell mass.

Participants/materials, setting, methods

Under the ethical review of Yokohama City University and informed consent with patients, we collected human surplus blastocysts those are donated after successful clinical treatment or discarded because of poor development grade. We biopsied multiple parts from one blastocyst and cultured the biopsied embryos, and extracted whole DNA from the biopsy samples and cultured embryos. Karyotyping by next generation sequencing were performed.

Main results and the role of chance

We analyzed 34 samples from 11 embryos, including 25 biopsy sample from 11 embryos and 9 cell mass from 7 cultured embryos. In the karyotype tracking results, even though biopsy sample analysis before the culture were uniformed aneuploid or chromosome mosaic, the developing embryo cell mass had normal karyotype. In one embryo as an example, among the three biopsied extra trophectoderm samples from that, two of them were mosaic, and one of them had uniformed chromosome 21 trisomy and chromosome 16 mosaic monosomy. But the embryo formed multiple cell mass in implantation assay. We examined karyotype of three cell mass, and the result from all were normal karyotype. We suggested that the chromosome aberration cells were screened in the human embryo development, and when the function was not carried out the embryo stopped the development.

Limitations, reasons for caution

Because of small number of samples available, we need more samples for a more accurate evaluation. Furthermore, we cannot evaluate the absolute mechanism that cells with chromosome aberration decreases.

Wider implications of the findings: Conventional PGT-A techniques are based on uniformed embryos developing hypothesized past time. As showed in some clinical reports, PGT-A can reduce of spontaneous abortion and chance of embryo transfer. Thinking about aneuploid cell purifying system in embryo development, effectiveness of PGT-A should be more questionable for infertility treatment.

Trial registration number

A200326004

Highly specific monoclonal antibodies and epitope identification against SARS-CoV-2 nucleocapsid protein for antigen detection tests

The ongoing coronavirus disease 2019 (COVID-19) pandemic is a major global public health concern. Although rapid point-of-care testing for detecting viral antigen is important for management of the outbreak, the current antigen tests are less sensitive than nucleic acid testing. In our current study, we produce monoclonal antibodies (mAbs) that exclusively react with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and exhibit no cross-reactivity with other human coronaviruses, including SARS-CoV. Molecular modeling suggests that the mAbs bind to epitopes present on the exterior surface of the nucleocapsid, making them suitable for detecting SARS-CoV-2 in clinical samples. We further select the optimal pair of anti-SARS-CoV-2 nucleocapsid protein (NP) mAbs using ELISA and then use this mAb pair to develop immunochromatographic assay augmented with silver amplification technology. Our mAbs recognize the variants of concern (501Y.V1-V3) that are currently in circulation. Because of their high performance, the mAbs of this study can serve as good candidates for developing antigen detection kits for COVID-19.

Cleavage of TANK-Binding Kinase 1 by HIV-1 Protease Triggers Viral Innate Immune Evasion

Type-I interferons (IFN-I) are the innate immune system’s principal defense against viral infections. Human immunodeficiency virus-1 (HIV-1) has evolved several ways to suppress or evade the host’s innate immunity in order to survive and replicate to sustain infection. Suppression of IFN-I is one among the multiple escape strategies used by HIV-1 to prevent its clearance. HIV-1 protease which helps in viral maturation has also been observed to cleave host cellular protein kinases. In this study we performed a comprehensive screening of a human kinase library using AlphaScreen assay and identified that TANK binding kinase-1 (TBK1) was cleaved by HIV-1 protease (PR). We demonstrate that PR cleaved TBK1 fails to phosphorylate IFN regulatory factor 3 (IRF3), thereby reducing the IFN-I promoter activity and further reveal that the PR mediated suppression of IFN-I could be counteracted by protease inhibitors (PI) in vitro. We have also revealed that mutations of HIV-1 PR that confer drug resistance to PIs reduce the enzyme’s ability to cleave TBK1. The findings of this study unearth a direct link between HIV-1 PR activity and evasion of innate immunity by the virus, the possible physiological relevance of which warrants to be determined.

Carbonic anhydrase 13 suppresses bone metastasis in breast cancer

Metastatic progression is the leading cause of mortality in breast cancer. However, molecular mechanisms that govern this process remain unclear. In this study, we found that carbonic anhydrase 13 (CA13) plays a potential role in suppressing bone metastasis. iRFP713-labeled iCSCL-10A (iRFP-iCSCL-10A) breast cancer cells, which exhibit the hallmarks of cancer stem cells, exerted the ability of bone metastasis in hind legs after 5-week injections, whereas no metastasis was observed in control iRFP713-labeled MCF-10A (iRFP-MCF10A) cells. Transcriptome analysis indicated that the expression of several genes, including metabolism-related CA13, was reduced in bone metastatic iRFP-iCSCL-10A cells. In vitro and in vivo analyses demonstrated that overexpression of CA13 in iRFP-iCSCL-10A cells suppressed migration, invasion, and bone metastasis, together with the reduction of VEGF-A and M-CSF expression. Furthermore, we found that breast cancer patients with a low CA13 expression had significantly shorter overall survival and disease-free survival rates compared to those with higher CA13 expression. These findings suggest that CA13 may act as a novel prognostic biomarker and would be a therapeutic candidate for the prevention of bone metastasis in breast cancer.

Zika virus protease induces caspase-independent pyroptotic cell death by directly cleaving gasdermin D

The association of Zika virus (ZIKV) infection with a congenital malformation in fetuses, neurological, and other systemic complications in adults have brought significant global health emergency. ZIKV targets nerve cells in the brain and causes cell death, such as pyroptosis, leading to neuroinflammation. Here we described a novel mechanism of pyroptosis caused by ZIKV protease. We found that ZIKV protease directly cleaved the GSDMD into N-terminal fragment (1-249) leading to pyroptosis in a caspase-independent manner, suggesting a direct mechanism of ZIKV-induced cell death and subsequent inflammation. Our findings might shed new light to explore the pathogenesis of ZIKV infections where ZIKV protease might be a suitable target for the development of antiviral agents.

A Hyperactive RelA/p65-Hexokinase 2 Signaling Axis Drives Primary Central Nervous System Lymphoma

Primary central nervous system lymphoma (PCNSL) is an isolated type of lymphoma of the central nervous system and has a dismal prognosis despite intensive chemotherapy. Recent genomic analyses have identified highly recurrent mutations of MYD88 and CD79B in immunocompetent PCNSL, whereas LMP1 activation is commonly observed in Epstein-Barr virus (EBV)-positive PCNSL. However, a lack of clinically representative preclinical models has hampered our understanding of the pathogenic mechanisms by which genetic aberrations drive PCNSL disease phenotypes. Here, we establish a panel of 12 orthotopic, patient-derived xenograft (PDX) models from both immunocompetent and EBV-positive PCNSL and secondary CNSL biopsy specimens. PDXs faithfully retained their phenotypic, metabolic, and genetic features, with 100% concordance of MYD88 and CD79B mutations present in PCNSL in immunocompetent patients. These models revealed a convergent functional dependency upon a deregulated RelA/p65-hexokinase 2 signaling axis, codriven by either mutated MYD88/CD79B or LMP1 with Pin1 overactivation in immunocompetent PCNSL and EBV-positive PCNSL, respectively. Notably, distinct molecular alterations used by immunocompetent and EBV-positive PCNSL converged to deregulate RelA/p65 expression and to drive glycolysis, which is critical for intracerebral tumor progression and FDG-PET imaging characteristics. Genetic and pharmacologic inhibition of this key signaling axis potently suppressed PCNSL growth in vitro and in vivo. These patient-derived models offer a platform for predicting clinical chemotherapeutics efficacy and provide critical insights into PCNSL pathogenic mechanisms, accelerating therapeutic discovery for this aggressive disease. SIGNIFICANCE: A set of clinically relevant CNSL xenografts identifies a hyperactive RelA/p65-hexokinase 2 signaling axis as a driver of progression and potential therapeutic target for treatment and provides a foundational preclinical platform. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/23/5330/F1.large.jpg.

Prolyl Isomerase Pin1 Regulates the Stability of Hepatitis B Virus Core Protein

The dynamic interplay between virus and host proteins is critical for establishing efficient viral replication and virus-induced pathogenesis. Phosphorylation-dependent prolyl isomerization by Pin1 provides a unique mechanism of molecular switching to control both protein function and stability. We demonstrate here that Pin1 binds and stabilizes hepatitis B virus core protein (HBc) in a phosphorylation-dependent manner, and promotes the efficient viral propagation. Phos-tag gel electrophoresis with various site-directed mutants of HBc revealed that Thr160 and Ser162 residues within the C terminal arginine-rich domain are phosphorylated concomitantly. GST pull-down assay and co-immunoprecipitation analysis demonstrated that Pin1 associated with phosphorylated HBc at the Thr160-Pro and Ser162-Pro motifs. Chemical or genetic inhibition of Pin1 significantly accelerated the rapid degradation of HBc via a lysosome-dependent pathway. Furthermore, we found that the pyruvate dehydrogenase phosphatase catalytic subunit 2 (PDP2) could dephosphorylate HBc at the Pin1-binding sites, thereby suppressing Pin1-mediated HBc stabilization. Our findings reveal an important regulatory mechanism of HBc stability catalyzed by Pin1 and may facilitate the development of new antiviral therapeutics targeting Pin1 function.

P897Diagnostic utility of tissue biopsy in transthyretin cardiac amyloidosis diagnosed by non-invasive diagnostic criteria

Background

In the recent past, transthyretin cardiac amyloidosis (TTR-CA) is recognized as an important cause of heart failure with preserved ejection fraction, and diagnostic utility of 99mTc-pyrophosphate (99mTc-PYP) scintigraphy in TTR-CA has been established. However, pathological evaluation is still the basis to confirm diagnosis. Subcutaneous tissue and gastrointestinal tract biopsy are useful examinations alternative to endomyocardial biopsy. Nevertheless, the positive ratio of amyloid deposition in these organs is not fully evaluated based on recent non-invasive diagnostic criteria.

Purpose

Our aim was to evaluate the diagnostic sensitivity of tissue biopsy in TTR-CA patients diagnosed by 99mTc-PYP scintigraphy.

Methods

We retrospectively evaluated 124 consecutive TTR-CA patients [wild-type (ATTRwt): 90, hereditary (hATTR): 34] who were diagnosed by positive findings of 99mTc-PYP scintigraphy (visual score 2 or 3) between June 2002 and January 2019 at our institute.

Results

A total of 114 patients underwent tissue biopsy at least one organ. Amyloid was detected on Congo red staining of subcutaneous tissue (43/97: 44%), gastrointestinal tract (52/78: 67%) and heart (78/79: 99%), respectively. Among 70 patients who underwent both subcutaneous tissue and gastrointestinal tract biopsy, amyloid was detected at least one specimen in 57/70 (81%). Compared to hATTR CA patients, ATTRwt CA patients had lower positive ratio of subcutaneous tissue (81% vs. 27%) and gastrointestinal tract (73% vs. 63%) biopsy.

Conclusion

Non-invasive diagnostic criteria of TTR-CA had excellent sensitivity of amyloid deposition in heart. The diagnostic sensitivity of subcutaneous tissue and gastrointestinal tract biopsy was lower in ATTRwt CA compared to hATTR CA. Combination of subcutaneous tissue and gastrointestinal tract biopsy was useful for pathological confirmation of amyloid deposition without endomyocardial biopsy.

TROY expression is associated with pathological stage and poor prognosis in patients treated with radical cystectomy

BACKGROUND

New biomarkers may help us provide individualized prognosis and allow risk-stratified clinical decision making about radical treatment.

OBJECTIVES

This study aimed to determine the tumor necrosis factor of receptor superfamily 19 (TROY) expression in urothelial carcinoma and its relationship to clinicopathological findings.

METHODS

Immunohistochemical staining for TROY was carried out in 136 archival radical cystectomy specimens with immunoreactivity being stratified on a 0-9 scale. Expression scores for TROY were further stratified into negative (score 0) and positive (score 1 or greater). Median age was 65 years, and the median follow-up period was 50.7 months.

RESULTS

Expression of TROY was significantly associated with the pathological stage (p= 0.019) and expression of nestin (p= 0.013). Log-rank tests indicated that expression of TROY was significantly associated with disease progression and cancer-specific mortality (p= 0.044 and 0.008, respectively). In multivariate Cox regression analysis, lymph node status was the only independent prognostic factor for disease progression and cancer-specific survival. Expression of TROY was a marginal prognostic factor for cancer-specific survival.

CONCLUSIONS

TROY may therefore be a new molecular marker to aid in identifying and selecting patients undergoing radical cystectomy who could potentially benefit from multimodal treatment.

PIM kinases facilitate lentiviral evasion from SAMHD1 restriction via Vpx phosphorylation

Lentiviruses have evolved to acquire an auxiliary protein Vpx to counteract the intrinsic host restriction factor SAMHD1. Although Vpx is phosphorylated, it remains unclear whether such phosphorylation indeed regulates its activity toward SAMHD1. Here we identify the PIM family of serine/threonine protein kinases as the factors responsible for the phosphorylation of Vpx and the promotion of Vpx-mediated SAMHD1 counteraction. Integrated proteomics and subsequent functional analysis reveal that PIM family kinases, PIM1 and PIM3, phosphorylate HIV-2 Vpx at Ser13 and stabilize the interaction of Vpx with SAMHD1 thereby promoting ubiquitin-mediated proteolysis of SAMHD1. Inhibition of the PIM kinases promotes the antiviral activity of SAMHD1, ultimately reducing viral replication. Our results highlight a new mode of virus–host cell interaction in which host PIM kinases facilitate promotion of viral infectivity by counteracting the host antiviral system, and suggest a novel therapeutic strategy involving restoration of SAMHD1-mediated antiviral response.

The accessory lentiviral protein X (Vpx) of the SIV_smm/mac and HIV-2 lineage targets the host-restriction factor SAMHD1 for proteasomal degradation. Here, the authors show that host PIM kinase-mediated phosphorylation of Vpx stabilizes its interaction with SAMHD1, suggesting PIM as potential antiviral targets.

PI3K/AKT/mTOR Pathway Alterations Promote Malignant Progression and Xenograft Formation in Oligodendroglial Tumors

PURPOSE

Oligodendroglioma has a relatively favorable prognosis, however, often undergoes malignant progression. We hypothesized that preclinical models of oligodendroglioma could facilitate identification of therapeutic targets in progressive oligodendroglioma. We established multiple oligodendroglioma xenografts to determine if the PI3K/AKT/mTOR signaling pathway drives tumor progression.

EXPERIMENTAL DESIGN

Two anatomically distinct tumor samples from a patient who developed progressive anaplastic oligodendroglioma (AOD) were collected for orthotopic transplantation in mice. We additionally implanted 13 tumors to investigate the relationship between PI3K/AKT/mTOR pathway alterations and oligodendroglioma xenograft formation. Pharmacologic vulnerabilities were tested in newly developed AOD models in vitro and in vivo.

RESULTS

A specimen from the tumor site that subsequently manifested rapid clinical progression contained a PIK3CA mutation E542K, and yielded propagating xenografts that retained the OD/AOD-defining genomic alterations (IDH1 ^R132H and 1p/19q codeletion) and PIK3CA ^E542K, and displayed characteristic sensitivity to alkylating chemotherapeutic agents. In contrast, a xenograft did not engraft from the region that was clinically stable and had wild-type PIK3CA. In our panel of OD/AOD xenografts, the presence of activating mutations in the PI3K/AKT/mTOR pathway was consistently associated with xenograft establishment (6/6, 100%). OD/AOD that failed to generate xenografts did not have activating PI3K/AKT/mTOR alterations (0/9, P < 0.0001). Importantly, mutant PIK3CA oligodendroglioma xenografts were vulnerable to PI3K/AKT/mTOR pathway inhibitors in vitro and in vivo-evidence that mutant PIK3CA is a tumorigenic driver in oligodendroglioma.

CONCLUSIONS

Activation of the PI3K/AKT/mTOR pathway is an oncogenic driver and is associated with xenograft formation in oligodendrogliomas. These findings have implications for therapeutic targeting of PI3K/AKT/mTOR pathway activation in progressive oligodendrogliomas.

A novel inhibitor of tumorspheres reveals the activation of the serine biosynthetic pathway upon mitochondrial inhibition

Differences in the metabolism of cancer cells or cancer stem cells (CSCs) as compared to normal cells have provided avenues to safely target cancers. To discover metabolic inhibitors of CSCs, we performed alkaline phosphatase- and tumoursphere-based drug screening using induced cancer stem cell-like cells. From the screening of a RIKEN NPDepo chemical library, we discovered NPD2381 as a novel and selective cancer-stemness inhibitor that targets mitochondrial metabolism. Using our ChemProteoBase profiling, we found that NPD2381 increases the expression of enzymes within the serine biosynthesis pathway. We also found a role for serine in protecting cancer cells from mitochondrial inhibitors. Our results suggest the existence of a compensatory mechanism to increase the level of intracellular serine in response to mitochondrial inhibitors.

Score-Based and Nutrient-Derived Dietary Patterns Are Associated with Depressive Symptoms in Community-Dwelling Older Japanese: A Cross-Sectional Study

OBJECTIVES

This study evaluated associations of score-based and nutrient-derived dietary patterns with depressive symptoms in community-dwelling older Japanese.

DESIGN

Cross-sectional study.

SETTING

Community-based.

PARTICIPANTS

982 community-dwelling adults aged 65 years or older.

MEASUREMENTS

Score-based pattern was assessed by using dietary variety score (DVS), which covers 10 food group items in Japanese meals. Nutrient-derived dietary patterns were identified by using reduced rank regression (RRR), with folate, vitamin C, magnesium, calcium, iron, and zinc intakes as response variables. Depressive symptoms were assessed with the Geriatric Depression Scale. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for these dietary patterns in multivariate logistic regression analyses with potential confounders. The lowest consumption category was used as the reference group.

RESULTS

The prevalence of depressive symptoms was 13.5%. Higher DVS was associated with fewer depressive symptoms (OR=0.52, 95% CI=0.27-1.03 for the highest vs the lowest DVS; P for trend=0.031). The first RRR dietary pattern score was characterized by high intakes of fish, soybean products, potatoes, most vegetables, mushrooms, seaweeds, fruits, and green tea and a low intake of rice and was inversely associated with the prevalence of depressive symptoms (OR=0.53, 95% CI=0.30-0.92; P for trend=0.030).

CONCLUSION

Greater dietary variety and a dietary pattern characterized by high intakes of fish, soybean products, potatoes, most vegetables, mushrooms, seaweeds, fruit, and green tea and a low intake of rice were consistently associated with lower prevalence of depressive symptoms in community-dwelling older Japanese. Therefore, both patterns identified the components of dietary habits essential to depression prevention.

Albumin, Hemoglobin, and the Trajectory of Cognitive Function in Community-Dwelling Older Japanese: A 13-Year Longitudinal Study

BACKGROUND

Cognitive function can substantially decline over a long period, and understanding the trajectory of cognitive function is important. However, little is known about the linkage between nutritional biomarkers and long-term cognitive change.

OBJECTIVES

We analyzed 13-year longitudinal data for older Japanese to examine the associations of serum albumin and hemoglobin levels with the trajectory of cognitive function.

DESIGN

Longitudinal study.

SETTING

Community-based.

PARTICIPANTS

A total of 1,744 community-dwelling adults aged 65 years or older who participated in annual health examinations in Kusatsu town, Gunma Prefecture, Japan, from 2002-2014.

MEASUREMENTS

Cognitive function was assessed annually by the Mini-Mental State Examination (MMSE). Albumin and hemoglobin levels at baseline (the year when a respondent first participated in the health examination) were divided into quartiles. Hierarchical linear modeling was used to analyze intrapersonal and interpersonal differences in cognitive function.

RESULTS

Participants' MMSE scores decreased at an accelerated rate over the 13-year period. Participants with the lowest baseline albumin level (below the first quartile line) showed a greater accelerated decline in MMSE scores over time, compared with those with the highest level (above the third quartile line). Moreover, MMSE scores in participants with a lower hemoglobin level and lower MMSE score at baseline tended to decline faster over time at an accelerated rate.

CONCLUSIONS

These findings yield new insights about the complex and diverse roles of these nutritional biomarkers on the trajectory of cognitive function in old age.