The tumor suppressor PTEN has a critical role in antiviral innate immunity.

The gene encoding PTEN is one of the most frequently mutated tumor suppressor-encoding genes in human cancer. While PTEN's function in tumor suppression is well established, its relationship to anti-microbial immunity remains unknown. Here we found a pivotal role for PTEN in the induction of type I interferon, the hallmark of antiviral innate immunity, that was independent of the pathway of the kinases PI(3)K and Akt. PTEN controlled the import of IRF3, a master transcription factor responsible for IFN-ß production, into the nucleus. We further identified a PTEN-controlled negative phosphorylation site at Ser97 of IRF3 and found that release from this negative regulation via the phosphatase activity of PTEN was essential for the activation of IRF3 and its import into the nucleus. Our study identifies crosstalk between PTEN and IRF3 in tumor suppression and innate immunity.

Asymmetric Synthesis and Biological Evaluation of Platensilin, Platensimycin, Platencin, and Their Analogs via a Bioinspired Skeletal Reconstruction Approach.

Platensilin, platensimycin, and platencin are potent inhibitors of ß-ketoacyl-acyl carrier protein synthase (FabF) in the bacterial and mammalian fatty acid synthesis system, presenting promising drug leads for both antibacterial and antidiabetic therapies. Herein, a bioinspired skeleton reconstruction approach is reported, which enables the unified synthesis of these three natural FabF inhibitors and their skeletally diverse analogs, all stemming from a common ent-pimarane core. The synthesis features a diastereoselective biocatalytic reduction and an intermolecular Diels-Alder reaction to prepare the common ent-pimarane core. From this intermediate, stereoselective Mn-catalyzed hydrogen atom-transfer hydrogenation and subsequent Cu-catalyzed carbenoid C-H insertion afford platensilin. Furthermore, the intramolecular Diels-Alder reaction succeeded by regioselective ring opening of the newly formed cyclopropane enables the construction of the bicyclo[3.2.1]-octane and bicyclo[2.2.2]-octane ring systems of platensimycin and platencin, respectively. This skeletal reconstruction approach of the ent-pimarane core facilitates the preparation of analogs bearing different polycyclic scaffolds. Among these analogs, the previously unexplored cyclopropyl analog 47 exhibits improved antibacterial activity (MIC80 = 0.0625 µg/mL) against S. aureus compared to platensimycin.

Efficacy of NVX-CoV2373 Covid-19 Vaccine against the B.1.351 Variant.

BACKGROUND: The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants threatens progress toward control of the coronavirus disease 2019 (Covid-19) pandemic. In a phase 1-2 trial involving healthy adults, the NVX-CoV2373 nanoparticle vaccine had an acceptable safety profile and was associated with strong neutralizing-antibody and antigen-specific polyfunctional CD4+ T-cell responses. Evaluation of vaccine efficacy was needed in a setting of ongoing SARS-CoV-2 transmission. METHODS: In this phase 2a-b trial in South Africa, we randomly assigned human immunodeficiency virus (HIV)-negative adults between the ages of 18 and 84 years or medically stable HIV-positive participants between the ages of 18 and 64 years in a 1:1 ratio to receive two doses of either the NVX-CoV2373 vaccine (5 µg of recombinant spike protein with 50 µg of Matrix-M1 adjuvant) or placebo. The primary end points were safety and vaccine efficacy against laboratory-confirmed symptomatic Covid-19 at 7 days or more after the second dose among participants without previous SARS-CoV-2 infection. RESULTS: Of 6324 participants who underwent screening, 4387 received at least one injection of vaccine or placebo. Approximately 30% of the participants were seropositive for SARS-CoV-2 at baseline. Among 2684 baseline seronegative participants (94% HIV-negative and 6% HIV-positive), predominantly mild-to-moderate Covid-19 developed in 15 participants in the vaccine group and in 29 in the placebo group (vaccine efficacy, 49.4%; 95% confidence interval [CI], 6.1 to 72.8). Vaccine efficacy among HIV-negative participants was 60.1% (95% CI, 19.9 to 80.1). Of 41 sequenced isolates, 38 (92.7%) were the B.1.351 variant. Post hoc vaccine efficacy against B.1.351 was 51.0% (95% CI, -0.6 to 76.2) among the HIV-negative participants. Preliminary local and systemic reactogenicity events were more common in the vaccine group; serious adverse events were rare in both groups. CONCLUSIONS: The NVX-CoV2373 vaccine was efficacious in preventing Covid-19, with higher vaccine efficacy observed among HIV-negative participants. Most infections were caused by the B.1.351 variant. (Funded by Novavax and the Bill and Melinda Gates Foundation; ClinicalTrials.gov number, NCT04533399.).

Sacculatane Diterpenoids from the Liverwort Plagiochila nitens Collected in China.

Seven new terpenoids, including six sacculatane diterpenoids plagiochilarins A-F (1-6), and one ent-2,3-seco-aromandrane sesquiterpenoid plagiochilarin H (8) with a 6/7/3/5 tetracyclic scaffold, alongside three known compounds, were obtained from the Chinese liverwort Plagiochila nitens Inoue. Plagiochilarin B (2) was unpredictably converted to the more stable artifact 7 under acid catalysis through cyclic ether formation. The reaction mechanism was reasonably deduced and experimentally verified. The structures of these terpenoids were determined by analysis of MS and NMR spectroscopic data and single-crystal X-ray diffraction. The inhibitory effect of all of the isolates was evaluated on the growth of two C. albicans strains, wild strain SC5314 and efflux pump-deficient strain DSY654. However, only plagiochilarin H (8) showed a MIC value of 16 µg/mL against C. albicans DSY654.

Immunogenicity and safety of heterologous Omicron BA.1 and bivalent SARS-CoV-2 recombinant spike protein booster vaccines: a phase 3, randomized, clinical trial.

BACKGROUND: Mutations present in emerging SARS-CoV-2 variants permit evasion of neutralization with prototype vaccines. A novel Omicron BA.1 subvariant-specific vaccine (NVX-CoV2515) was tested alone, or as a bivalent preparation in combination with the prototype vaccine (NVX-CoV2373), to assess antibody responses to SARS-CoV-2. METHODS: Participants aged 18 to 64 years immunized with 3 doses of prototype mRNA vaccines were randomized 1:1:1 to receive a single dose of NVX-CoV2515, NVX-CoV2373, or bivalent mixture in a phase 3 study investigating heterologous boosting with SARS-CoV-2 recombinant spike protein vaccines. Immunogenicity was measured 14 and 28 days after vaccination for the SARS-CoV-2 Omicron BA.1 sublineage and ancestral strain. Safety profiles of vaccines were assessed. RESULTS: Of participants who received trial vaccine (N = 829), those administered NVX-CoV2515 (n = 286) demonstrated superior neutralizing antibody response to BA.1 versus NVX-CoV2373 (n = 274) at Day 14 (geometric mean titer ratio [95% CI]: 1.6 [1.33, 2.03]). Seroresponse rates [n/N; 95% CI] were 73.4% [91/124; 64.7, 80.9] for NVX-CoV2515 versus 50.9% [59/116; 41.4, 60.3] for NVX-CoV2373. All formulations were similarly well-tolerated. CONCLUSIONS: NVX-CoV2515 elicited a superior neutralizing antibody response against the Omicron BA.1 subvariant compared with NVX-CoV2373 when administered as a fourth dose. Safety data were consistent with the established safety profile of NVX-CoV2373.

Phase 1-2 Trial of a SARS-CoV-2 Recombinant Spike Protein Nanoparticle Vaccine.

BACKGROUND: NVX-CoV2373 is a recombinant severe acute respiratory syndrome coronavirus 2 (rSARS-CoV-2) nanoparticle vaccine composed of trimeric full-length SARS-CoV-2 spike glycoproteins and Matrix-M1 adjuvant. METHODS: We initiated a randomized, placebo-controlled, phase 1-2 trial to evaluate the safety and immunogenicity of the rSARS-CoV-2 vaccine (in 5-µg and 25-µg doses, with or without Matrix-M1 adjuvant, and with observers unaware of trial-group assignments) in 131 healthy adults. In phase 1, vaccination comprised two intramuscular injections, 21 days apart. The primary outcomes were reactogenicity; laboratory values (serum chemistry and hematology), according to Food and Drug Administration toxicity scoring, to assess safety; and IgG anti-spike protein response (in enzyme-linked immunosorbent assay [ELISA] units). Secondary outcomes included unsolicited adverse events, wild-type virus neutralization (microneutralization assay), and T-cell responses (cytokine staining). IgG and microneutralization assay results were compared with 32 (IgG) and 29 (neutralization) convalescent serum samples from patients with Covid-19, most of whom were symptomatic. We performed a primary analysis at day 35. RESULTS: After randomization, 83 participants were assigned to receive the vaccine with adjuvant and 25 without adjuvant, and 23 participants were assigned to receive placebo. No serious adverse events were noted. Reactogenicity was absent or mild in the majority of participants, more common with adjuvant, and of short duration (mean, ≤2 days). One participant had mild fever that lasted 1 day. Unsolicited adverse events were mild in most participants; there were no severe adverse events. The addition of adjuvant resulted in enhanced immune responses, was antigen dose-sparing, and induced a T helper 1 (Th1) response. The two-dose 5-µg adjuvanted regimen induced geometric mean anti-spike IgG (63,160 ELISA units) and neutralization (3906) responses that exceeded geometric mean responses in convalescent serum from mostly symptomatic Covid-19 patients (8344 and 983, respectively). CONCLUSIONS: At 35 days, NVX-CoV2373 appeared to be safe, and it elicited immune responses that exceeded levels in Covid-19 convalescent serum. The Matrix-M1 adjuvant induced CD4+ T-cell responses that were biased toward a Th1 phenotype. (Funded by the Coalition for Epidemic Preparedness Innovations; ClinicalTrials.gov number, NCT04368988).

Pinguisane Sesquiterpenoids from the Chinese Liverwort Trocholejeunea sandvicensis and Their Anti-Inflammatory Activity.

Nine new pinguisane sesquiterpenoid compounds, 1-9, including a highly oxygenated compound (1) and two amides (7 and 8), along with three known compounds (10, 11, and 12), were isolated from the Chinese liverwort Trocholejeunea sandvicensis Mizut (Lejeuneaceae). The structures of these compounds were determined by analysis of IR, UV, HRESIMS, NMR spectroscopic data, electronic circular dichroism calculations, and single-crystal X-ray diffraction analysis. Inhibitory effects against lipopolysaccharide (LPS)-induced NO production in RAW 264.7 murine macrophages indicated that the maximum inhibition rates of NO production of compounds 1, 9, and 10 were 83.15%, 83.54%, and 96.28% under the nontoxic tested concentration, respectively. Compound 9 also displayed moderate anti-inflammatory activity in vivo in a CuSO4-induced transgenic zebrafish model.

Unprecedented 4,9-Seco-Oplopanane and Seven Drimane Sesquiterpenoids from the Chinese Liverwort Lejeunea flava (Sw.) Nees.

An unprecedented 4,9-seco-oplopanane (1), two undescribed drimane epimers (2 and 3), and five known drimane sesquiterpenoids (4-8) were isolated from the Chinese liverwort Lejeunea flava (Sw.) Nees. The structures of the new sesquiterpenoids were determined using nuclear magnetic resonance spectroscopy, electronic circular dichroism calculations, and single-crystal X-ray diffraction measurements. The inhibitory capacity of the new compounds against nitric oxide production in lipopolysaccharide-induced RAW 264.7 murine macrophages, along with the cytotoxicity of the new compounds against A549 and HepG-2 human cancer cell lines, were discussed.

Induction of Cross-Reactive Hemagglutination Inhibiting Antibody and Polyfunctional CD4+ T-Cell Responses by a Recombinant Matrix-M-Adjuvanted Hemagglutinin Nanoparticle Influenza Vaccine.

BACKGROUND: Recurrent reports of suboptimal influenza vaccine effectiveness have renewed calls to develop improved, broadly cross-protective influenza vaccines. Here, we evaluated the safety and immunogenicity of a novel, saponin (Matrix-M)-adjuvanted, recombinant hemagglutinin (HA) quadrivalent nanoparticle influenza vaccine (qNIV). METHODS: We conducted a randomized, observer-blind, comparator-controlled (trivalent high-dose inactivated influenza vaccine [IIV3-HD] or quadrivalent recombinant influenza vaccine [RIV4]), safety and immunogenicity trial of qNIV (5 doses/formulations) in healthy adults ≥65 years. Vaccine immunogenicity was measured by hemagglutination-inhibition assays using reagents that express wild-type hemagglutination inhibition (wt-HAI) sequences and cell-mediated immune responses. RESULTS: A total of 1375 participants were randomized, immunized, and followed for safety and immunogenicity. Matrix-M-adjuvanted qNIV induced superior wt-HAI antibody responses against 5 of 6 homologous or drifted strains compared with unadjuvanted qNIV. Adjuvanted qNIV induced post-vaccination wt-HAI antibody responses at day 28 that were statistically higher than IIV3-HD against a panel of homologous or drifted A/H3N2 strains, similar to IIV3-HD against homologous A/H1N1 and B (Victoria) strains and similar to RIV4 against all homologous and drifted strains evaluated. The qNIV formulation with 75 µg Matrix-M adjuvant induced substantially higher post-vaccination geometric mean fold increases of influenza HA-specific polyfunctional CD4+ T cells compared with IIV3-HD or RIV4. Overall, similar frequencies of solicited and unsolicited adverse events were reported in all treatment groups. CONCLUSIONS: qNIV with 75 µg Matrix-M adjuvant was well tolerated and induced robust antibody and cellular responses, notably against both homologous and drifted A/H3N2 viruses. Further investigation in a pivotal phase 3 trial is underway. CLINICAL TRIALS REGISTRATION: NCT03658629.

Terpenoids from Chinese Liverworts Scapania spp.

An investigation of the chemical composition of Chinese liverworts led to the isolation of six new caged clerodane-type diterpenoids, scaparins A-C (1-3) from Scapania koponenii and scaparins D-F (4-6) from S. verrucosa. An unknown ent-trachylobane diterpenoid (7) and three known terpenoid derivatives (8-10) were obtained from S. verrucosa. The structures of the compounds were established on the basis of physical data (IR, UV, HRESIMS, and 1D and 2D NMR), and the absolute configurations were unequivocally confirmed by comparison of the experimental and calculated electronic circular dichroism spectra. Preliminary bioassays showed that compounds 1-7 exhibited moderate to weak quinone reductase-inducing activity in Hepa-1c1c7 cells.

Find Outliers of Image Edge Consistency by Weighted Local Linear Regression with Equality Constraints.

In this paper, we propose a general method to detect outliers from contaminated estimates of various image estimation applications. The method does not require any prior knowledge about the purpose, theory or hardware of the application but simply relies on the law of edge consistency between sources and estimates. The method is termed as ALRe (anchored linear residual) because it is based on the residual of weighted local linear regression with an equality constraint exerted on the measured pixel. Given a pair of source and contaminated estimate, ALRe offers per-pixel outlier likelihoods, which can be used to compose the data weights of post-refinement algorithms, improving the quality of refined estimate. ALRe has the features of asymmetry, no false positive and linear complexity. Its effectiveness is verified on four applications, four post-refinement algorithms and three datasets. It demonstrates that, with the help of ALRe, refined estimates are better in the aspects of both quality and edge consistency. The results are even comparable to model-based and hardware-based methods. Accuracy comparison on synthetic images shows that ALRe could detect outliers reliably. It is as effective as the mainstream weighted median filter at spike detection and is significantly better at bad region detection.

Enantioselective Total Syntheses of Manginoids†A and†C and Guignardones†A and†C.

An enantioselective synthetic approach for preparing manginoids and guignardones, two types of biogenetically related meroterpenoids, is reported. This bioinspired and divergent synthesis employs an oxidative 1,3-dicarbonyl radical-initiated cyclization and cyclodehydration of the common precursor to forge the central ring of the manginoids and guignardones, respectively, at a late stage. Key synthetic steps include silica-gel-promoted semipinacol rearrangement to form the 6-oxabicyclo[3.2.1]octane skeleton and the Suzuki-Miyaura reaction of vinyl bromide to achieve fragment coupling. This synthesis protocol enables the asymmetric syntheses of four fungal meroterpenoids from commercially available materials.

[Biosynthetic pathways of Polygonatum cyrtonema polysaccharide and diosgenin based on its transcriptomic data].

Polygonatum cyrtonema belongs to the plant family Liliaceae, and its dried rhizome is one of the sources of Chinese traditional medicine of Polygonati Rhizoma. It possesses the dual function as both medicine and food. Its main chemical components are polysaccharides and saponins. In order to understand the biosynthesis pathway of polysaccharides and diosgenin in P. cyrtonema, the corresponding transcriptomic data were obtained by extracting and sequencing the RNA of four parts of P. cyrtonema, namely, leaves, stems, rhizomes and roots. By adopting BGISEQ-500 sequencing platform, 42.03 Gb data were retrieved. Subsequently, the de novo assembly was carried out by Trinity software to obtain 137 233 transcripts, of which 68.13% of unigenes were annotated in seven databases including KEGG, GO, NR, NT, SwissProt, Pfam and KOG. Transcripts that may be involved in the biosynthesis of polysaccharides and diosgenin were analyzed by data mining. With help of qPCR, we validated expression data of four genes that were possibly involved in the biosynthesis of target metabolites. This experiment provides data for the study of biosynthetic pathways of P. cyrtonema secondary metabolites and the clarification of related structural gene functions.

Divergent Total Synthesis of Euphoranginol†C, Euphoranginone†D, ent-Trachyloban-3ß-ol, ent-Trachyloban-3-one, Excoecarin†E, and ent-16α-Hydroxy-atisane-3-one.

A divergent synthetic approach to biogenetically related diterpenoids such as ent-kauranes, ent-trachylobanes, ent-beyerane, and ent-atisane has been developed. The unified synthetic route involves the De Mayo reaction to rapidly generate the bicyclo[3.2.1]-octane moiety of ent-kaurane. The key reactions also include bioinspired nucleophilic cyclopropanation generating the [3.2.1.02,7 ]-tricyclic core of ent-trachylobane and regioselective cyclopropane fragmentation furnishing ent-beyerane and ent-atisane through the nucleophilic attack and protonation of the cyclopropane ring. This strategy enables the asymmetric total syntheses of six diterpenoids from the commercially available geraniol.

Bipartite Nuclear Localization Signal Controls Nuclear Import and DNA-Binding Activity of IFN Regulatory Factor 3.

Accurate cellular localization plays a crucial role in the effective function of most signaling proteins, and nuclear trafficking is central to the function of transcription factors. IFN regulatory factor (IRF)3 is a master transcription factor responsible for the induction of type I IFN, which plays a crucial role in host antiviral innate immune responses. However, the mechanisms for control and regulation of IRF3 nuclear import largely remain to be elucidated. In our study, we identified a bipartite nuclear localization signal (NLS) in IRF3, with two interdependent basic clusters separated by a 7-aa linker. Our study further demonstrated that the bipartite NLS of IRF3 is also critical for IRF3 DNA-binding activity, indicating that the two functions of this region are integrated, which is in contrast to other IRFs. Furthermore, the IFN bioassay and infection studies suggest that IRF3 NLS is essential to the IRF3-mediated IFN responses and antiviral immunity. Overall, our results reveal a previously unrecognized bipartite NLS for IRF3 that contains both DNA-binding activity and nuclear import function, and they shed light on the regulatory mechanisms of IRF3 activation and IRF3-mediated antiviral responses.

The vasodilatory effect of sulfur dioxide via SGC/cGMP/PKG pathway in association with sulfhydryl-dependent dimerization.

The present study was designed to explore the role of soluble guanylate cyclase (sGC)/cyclic guanosine monophosphate (cGMP)/PKG pathway in sulfur dioxide (SO2)-induced vasodilation. We showed that SO2 induced a concentration-dependent relaxation of phenylephrine (PE)-precontracted rat aortic rings in association with an increase in cGMP concentration, whereas l-aspartic acid ß-hydroxamate (HDX), an inhibitor of SO2 synthase, contracted rings in a dose-dependent manner. Pretreatment of aortic rings with the sGC inhibitor ODQ (30 µM) attenuated the vasodilatory effects of SO2, suggesting the involvement of cGMP pathway in SO2-induced vasodilation. Mechanistically, SO2 upregulated the protein levels of sGC and PKG dimers, while HDX inhibited it, indicating SO2 could promote cGMP synthesis through sGC activation. Furthermore, the dimerization of sGC and PKG and vasodilation induced by SO2 in precontracted rings were significantly prevented by thiol reductants dithiothreitol (DTT). In addition, SO2 reduced the activity of phosphodiesterase type 5 (PDE5), a cGMP-specific hydrolytic enzyme, implying that SO2 elevated cGMP concentration by inhibiting its hydrolysis. Hence, SO2 exerted its vasodilatory effects at least partly by promoting disulfide-dependent dimerization of sGC and PKG, resulting in an activated sGC/cGMP/PKG pathway in blood vessels. These findings revealed a new mode of action and mechanisms by which SO2 regulated the vascular tone.

Hydrogen sulfide suppresses oxidized low-density lipoprotein (ox-LDL)-stimulated monocyte chemoattractant protein 1 generation from macrophages via the nuclear factor κB (NF-κB) pathway.

This study was designed to examine the role of hydrogen sulfide (H2S) in the generation of oxidized low-density lipoprotein (ox-LDL)-stimulated monocyte chemoattractant protein 1 (MCP-1) from macrophages and possible mechanisms. THP-1 cells and RAW macrophages were pretreated with sodium hydrosulfide (NaHS) and hexyl acrylate and then treated with ox-LDL. The results showed that ox-LDL treatment down-regulated the H2S/cystathionine-ß-synthase pathway, with increased MCP-1 protein and mRNA expression in both THP-1 cells and RAW macrophages. Hexyl acrylate promoted ox-LDL-induced inflammation, whereas the H2S donor NaHS inhibited it. NaHS markedly suppressed NF-κB p65 phosphorylation, nuclear translocation, DNA binding activity, and recruitment to the MCP-1 promoter in ox-LDL-treated macrophages. Furthermore, NaHS decreased the ratio of free thiol groups in p65, whereas the thiol reductant DTT reversed the inhibiting effect of H2S on the p65 DNA binding activity. Most importantly, site-specific mutation of cysteine 38 to serine in p65 abolished the effect of H2S on the sulfhydration of NF-κB and ox-LDL-induced NF-κB activation. These results suggested that endogenous H2S inhibited ox-LDL-induced macrophage inflammation by suppressing NF-κB p65 phosphorylation, nuclear translocation, DNA binding activity, and recruitment to the MCP-1 promoter. The sulfhydration of free thiol group on cysteine 38 in p65 served as a molecular mechanism by which H2S inhibited NF-κB pathway activation in ox-LDL-induced macrophage inflammation.

Down-regulated CBS/H2S pathway is involved in high-salt-induced hypertension in Dahl rats.

BACKGROUND: The study was designed to explore the significance of endogenous H2S in the development of high-salt-induced hypertension in rats. METHODS: High-salt-induced hypertension rat model was made by feeding Dahl rat high-salt diet containing 8% NaCl for 8 weeks with SD rats as control. SBP and aorta structure in rats were observed. Endogenous H2S content and expression of cystathionine ß-lyase (CBS), cystathionine γ-lyase and mercaptopyruvate sulfurtransferase in renal tissues were detected. Mechanisms for the impact of high-salt on CBS/H2S in renal tissues were studied, targeting HIF-1α pathway. The effect of H2S on RAS in serum and renal tissue of rats were tested. RESULTS: High-salt reduced endogenous H2S content and inhibited the expression of CBS in renal tissue in salt-sensitive Dahl rats. H2S donor, however, inhibited salt-sensitive hypertension, reversed aortic structural remodeling and inhibited activation of the RAS system in renal tissues in Dahl rats. Expression of HIF-1α was decreased but expression of PHD2 was increased in renal tissue of Dahl rats with high-salt diet, whereas they did not alter in renal tissue of SD rats with high-salt diet. Ex vivo experiment showed that inhibitor of HIF-1α degradation could rescue down-regulated CBS/H2S pathway in renal tissue of Dahl rats with high-salt. In contrast, inhibitor of HIF-1α activity decreased the CBS/H2S pathway in the renal tissue of SD rats treated with high-salt. CONCLUSIONS: Down-regulated CBS/H2S pathway in renal tissues under high-salt insult might be an important pathogenesis of salt-sensitive hypertension.