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Background and ObjectivesShort-chain fatty acids (SCFAs) are gut microbial metabolites that promote the disease process in a rodent model of Parkinson disease (PD), but fecal levels of SCFAs in patients with PD are reduced. Simultaneous assessments of fecal and plasma SCFA levels, and their interrelationships with the PD disease process, are scarce. We aimed to compare fecal and plasma levels of different SCFA subtypes in patients with PD and healthy controls to delineate their interrelations and link to gut microbiota changes and clinical severity of PD.MethodsA cohort of 96 patients with PD and 85 controls were recruited from National Taiwan University Hospital. Fecal and plasma concentrations of SCFAs were measured using chromatography and mass spectrometry. Gut microbiota was analyzed using metagenomic shotgun sequencing. Body mass index and medical comorbidities were evaluated and dietary information was obtained using a food frequency questionnaire. To assess motor and cognitive impairment, we used the Movement Disorder Society–Unified Parkinson's Disease Rating Scale (MDS-UPDRS) and the Mini-Mental Status Examination (MMSE).ResultsCompared with controls, patients with PD had lower fecal but higher plasma concentrations of acetate, propionate, and butyrate. After adjustment for age, sex, disease duration, and anti-PD medication dosage, MDS-UPDRS part III motor scores correlated with reduced fecal levels of acetate (ρ = −0.37, p = 0.012), propionate (ρ = −0.32, p = 0.036), and butyrate (ρ = −0.40, p = 0.004) and with increased plasma propionate concentrations (ρ = 0.26, p = 0.042) in patients with PD. MMSE scores negatively correlated with plasma levels of butyrate (ρ = −0.09, p = 0.027) and valerate (ρ = −0.032, p = 0.033) after adjustment for confounders. SCFAs-producing gut bacteria correlated positively with fecal levels of SCFAs in healthy controls but revealed no association in patients with PD. In the PD patient group, the abundance of proinflammatory microbes, such as Clostridiales bacterium NK3B98 and Ruminococcus sp AM07-15, significantly correlated with decreased fecal levels and increased plasma levels of SCFAs, especially propionic acid.DiscussionReductions in fecal SCFAs but increased plasma SCFAs were observed in patients with PD and corelated to specific gut microbiota changes and the clinical severity of PD.Classification of EvidenceThis study provides Class III evidence that gut metabolite SCFAs distinguish between patients with PD and controls and are associated with disease severity in patients with PD.

Background: Emerging evidence suggests that gut dysbiosis contributes to Parkinson’s disease (PD) by signaling through microbial metabolites. Hippuric acid (HA), indole derivatives, and secondary bile acids are among the most common gut metabolites. Objective: To examine the relationship of systemic concentrations of these microbial metabolites associated with changes of gut microbiota, PD status, and severity of PD. Methods: We enrolled 56 patients with PD and 43 age- and sex-matched healthy participants. Motor and cognitive severity were assessed with Movement Disorder Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) part III motor score and the Mini-Mental State Examination (MMSE), respectively. Plasma concentrations of targeted gut metabolites were measured with liquid chromatography-tandem mass spectrometry. Gut microbiota was analyzed with shotgun metagenomic sequencing. Results: Compared with controls, PD patients had significantly higher plasma levels of HA, indole-3-propionic acid (IPA), deoxycholic acid (DCA), and glycodeoxycholic acid (GDCA). After adjustment for age and sex in a multivariate logistic regression analysis, plasma levels of HA (odds ratio [OR] 3.21, p

A major challenge to end the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is to develop a broadly protective vaccine that elicits long-term immunity. As the key immunogen, the viral surface spike (S) protein is frequently mutated, and conserved epitopes are shielded by glycans. Here, we revealed that S protein glycosylation has site-differential effects on viral infectivity. We found that S protein generated by lung epithelial cells has glycoforms associated with increased infectivity. Compared to the fully glycosylated S protein, immunization of S protein with N-glycans trimmed to the mono-GlcNAc–decorated state (S MG ) elicited stronger immune responses and better protection for human angiotensin-converting enzyme 2 (hACE2) transgenic mice against variants of concern (VOCs). In addition, a broadly neutralizing monoclonal antibody was identified from S MG -immunized mice that could neutralize wild-type SARS-CoV-2 and VOCs with subpicomolar potency. Together, these results demonstrate that removal of glycan shields to better expose the conserved sequences has the potential to be an effective and simple approach for developing a broadly protective SARS-CoV-2 vaccine.

A major challenge to end the pandemic caused by SARS-CoV-2 is to develop a broadly protective vaccine. As the key immunogen, the spike protein is frequently mutated with conserved epitopes shielded by glycans. Here, we reveal that spike glycosylation has site-differential effects on viral infectivity and lung epithelial cells generate spike with more infective glycoforms. Compared to the fully glycosylated spike, immunization of spike protein with N-glycans trimmed to the monoglycosylated state (Smg) elicits stronger immune responses and better protection for hACE2 transgenic mice against variants of concern. In addition, a broadly neutralizing monoclonal antibody was identified from the Smg immunized mice, demonstrating that removal of glycan shields to better expose the conserved sequences is an effective and simple approach to broad-spectrum vaccine development.One-Sentence SummaryRemoving glycan shields to expose conserved epitopes is an effective approach to develop a broad-spectrum SARS-CoV-2 vaccine.

Vaccination has been used to control the spread of seasonal flu; however, the virus continues to evolve and escape from host immune response through mutation and increasing glycosylation. Efforts have been directed toward development of a universal vaccine with broadly protective activity against multiple influenza strains and subtypes. Here we report the design and evaluation of various chimeric vaccines based on the most common avian influenza H5 and human influenza H1 sequences. Of these constructs, the chimeric HA (cHA) vaccine with consensus H5 as globular head and consensus H1 as stem was shown to elicit broadly protective CD4(+) and CD8(+) T cell responses. Interestingly, the monoglycosylated cHA (cHA(mg)) vaccine with GlcNAc on each glycosite induced more stem-specific antibodies, with higher antibody-dependent cellular cytotoxicity (ADCC), and better neutralizing and stronger cross-protection activities against H1, H3, H5, and H7 strains and subtypes. Moreover, the cHA(mg) vaccine combined with a glycolipid adjuvant designed for class switch further enhanced the vaccine efficacy with more IFN-γ, IL-4, and CD8(+) memory T cells produced.

Hemagglutinin (HA) is the immunodominant protein of the influenza virus. We previously showed that mice injected with a monoglycosylated influenza A HA (HAmg) produced cross-strain-reactive antibodies and were better protected than mice injected with a fully glycosylated HA (HAfg) during lethal dose challenge. We employed a single B-cell screening platform to isolate the cross-protective monoclonal antibody (mAb) 651 from mice immunized with the HAmg of A/Brisbane/59/2007 (H1N1) influenza virus (Bris/07). The mAb 651 recognized the head domain of a broad spectrum of HAs from groups 1 and 2 influenza A viruses and offered prophylactic and therapeutic efficacy against A/California/07/2009 (H1N1) (Cal/09) and Bris/07 infections in mice. The antibody did not possess neutralizing activity; however, antibody-dependent cellular cytotoxicity and antibody-dependent cellular phagocytosis mediated by natural killer cells and alveolar macrophages were important in the protective efficacy of mAb 651. Together, this study highlighted the significance of effector functions for non-neutralizing antibodies to exhibit protection against influenza virus infection., Author summary The protective efficacy of antibodies is generally related to their neutralization potency. Here, we isolated a monoclonal antibody from mice injected with monoglycosylated hemagglutinin protein-based universal influenza vaccine, and demonstrated a head-domain recognizing, but non-neutralizing, monoclonal antibody carried prophylactic and therapeutic efficacy against a broad spectrum of influenza virus infections in vivo via effector functions.

The development of a universal influenza vaccine has become a major effort to combat the high mutation rate of influenza. To explore the use of the highly conserved stem region of hemagglutinin (HA) as a universal vaccine, we produced HA-stem-based protein using yeast expression systems. The glycosylation effects on the immunogenicity and protection activities were investigated. The yield of the A/Brisbane/59/2007 HA stem produced from Pichia pastoris reached 100 mg/l. The immunogenicity of HA stem proteins in various glycoforms was further investigated and compared. All glycoforms of the HA stem protein can induce cross-reactive antibody responses, antibody-dependent cellular cytotoxicity (ADCC)-mediated protection as well as T-cell responses, with broad protection in mice. The monoglycosylated form of the A/Brisbane/59/2007 HA stem produced in yeast, together with the glycolipid C34 as the adjuvant, can elicit greater ADCC responses, better neutralizing activities against heterologous strains, and broader protection in mice.

Moenomycin inhibits bacterial growth by blocking the transglycosylase activity of class A penicillin-binding proteins (PBPs), which are key enzymes in bacterial cell wall synthesis. We compared the binding affinities of moenomycin A with various truncated PBPs by using surface plasmon resonance analysis and found that the transmembrane domain is important for moenomycin binding. Full-length class A PBPs from 16 bacterial species were produced, and their binding activities showed a correlation with the antimicrobial activity of moenomycin against Enterococcus faecalis and Staphylococcus aureus . On the basis of these findings, a fluorescence anisotropy-based high-throughput assay was developed and used successfully for identification of transglycosylase inhibitors.

This article describes system design for an Open Mobile Alliance Service Interoperability Test Platform called NTP-SIOT. Based on the TTCN-3 specifications, we show how 4G mobile applications such as OMA multimedia messaging service can be tested in this platform

The rapid genetic drift of influenza virus hemagglutinin is an obstacle to vaccine efficacy. Previously, we found that the consensus hemagglutinin DNA vaccine (pCHA5) can only elicit moderate neutralization activities toward the H5N1 clade 2.1 and clade 2.3 viruses. Two approaches were thus taken to improve the protection broadness of CHA5. The first one was to include certain surface amino acids that are characteristic of clade 2.3 viruses to improve the protection profiles. When we immunized mice with CHA5 harboring individual mutations, the antibodies elicited by CHA5 containing P157S elicited higher neutralizing activity against the clade 2.3 viruses. Likewise, the viruses pseudotyped with hemagglutinin containing 157S became more susceptible to neutralization. The second approach was to update the consensus sequence with more recent H5N1 strains, generating a second-generation DNA vaccine pCHA5II. We showed that pCHA5II was able to elicit higher cross-neutralization activities against all H5N1 viruses. Comparison of the neutralization profiles of CHA5 and CHA5II, and the animal challenge studies, revealed that CHA5II induced the broadest protection profile. We concluded that CHA5II combined with electroporation delivery is a promising strategy to induce antibodies with broad cross-reactivities against divergent H5N1 influenza viruses.

A library of 27 sialosides, including seventeen 2,3-linked and ten 2,6-linked glycans, has been prepared to construct a glycan array and used to profile the binding specificity of different influenza hemagglutinins (HA) subtypes, especially from the 2009 swine-originated H1N1 and seasonal influenza viruses. It was found that the HAs from the 2009 H1N1 and the seasonal Brisbane strain share similar binding profiles yet different binding affinities toward various α2,6 sialosides. Analysis of the binding profiles of different HA subtypes indicate that a minimum set of 5 oligosaccharides can be used to differentiate influenza H1, H3, H5, H7, and H9 subtypes. In addition, the glycan array was used to profile the binding pattern of different influenza viruses. It was found that most binding patterns of viruses and HA proteins are similar and that glycosylation at Asn27 is essential for receptor binding.

Many mobile data services have been developed. Before commercial launch of a data service, it is required to ensure that the service is implemented securely and correctly on a mobile device. To address this issue, Open Mobile Alliance (OMA) has defined test specifications to guarantee the conformance of data services on mobile devices. This paper describes a conformance test tool called NTP-DownloadT for OMA Download services. We discuss OMA Download requirements such as content discovery, authentication, delivery negotiation, content delivery and delivery confirmation. In this paper, we demonstrate how OMA Download test suite can be implemented to realise conformance tests.