Search

ABSTRACT Serum titers of SARS-CoV-2-neutralizing antibodies (nAbs) correlate well with protection from symptomatic COVID-19 but decay rapidly in the months following vaccination or infection. In contrast, measles-protective nAb titers are lifelong after measles vaccination, possibly due to persistence of the live-attenuated virus in lymphoid tissues. We, therefore, sought to generate a live recombinant measles vaccine capable of driving high SARS-CoV-2 nAb responses. Since previous clinical testing of a live measles vaccine encoding a SARS-CoV-2 spike glycoprotein resulted in suboptimal anti-spike antibody titers, our new vectors were designed to encode prefusion-stabilized SARS-CoV-2 spike glycoproteins, trimerized via an inserted peptide domain, and displayed on a dodecahedral miniferritin scaffold. Additionally, to circumvent the blunting of vaccine efficacy by preformed anti-measles antibodies, we extensively modified the measles surface glycoproteins. Comprehensive in vivo mouse testing demonstrated the potent induction of high titer nAbs in measles-immune mice and confirmed the significant contributions to overall potency afforded by prefusion stabilization, trimerization, and miniferritin display of the SARS-CoV-2 spike glycoprotein. In animals primed and boosted with a measles virus (MeV) vaccine encoding the ancestral SARS-CoV-2 spike, high-titer nAb responses against ancestral virus strains were only weakly cross-reactive with the Omicron variant. However, in primed animals that were boosted with a MeV vaccine encoding the Omicron BA.1 spike, antibody titers to both ancestral and Omicron strains were robustly elevated, and the passive transfer of serum from these animals protected K18-ACE2 mice from infection and morbidity after exposure to BA.1 and WA1/2020 strains. Our results demonstrate that by engineering the antigen, we can develop potent measles-based vaccine candidates against SARS-CoV-2.IMPORTANCEAlthough the live-attenuated measles virus (MeV) is one of the safest and most efficacious human vaccines, a measles-vectored COVID-19 vaccine candidate expressing the SARS-CoV-2 spike failed to elicit neutralizing antibody (nAb) responses in a phase-1 clinical trial, especially in measles-immune individuals. Here, we constructed a comprehensive panel of MeV-based COVID-19 vaccine candidates using a MeV with extensive modifications on the envelope glycoproteins (MeV-MR). We show that artificial trimerization of the spike is critical for the induction of nAbs and that their magnitude can be significantly augmented when the spike protein is synchronously fused to a dodecahedral scaffold. Furthermore, preexisting measles immunity did not abolish heterologous immunity elicited by our vector. Our results highlight the importance of antigen optimization in the development of spike-based COVID-19 vaccines and therapies.

Upon water loss, some organisms pause their life cycles and escape death. While widespread in microbes, this is less common in animals. Aedes mosquitoes are vectors for viral diseases. Aedes eggs can survive dry environments, but molecular and cellular principles enabling egg survival through desiccation remain unknown. In this report, we find that Aedes aegypti eggs, in contrast to Anopheles stephensi, survive desiccation by acquiring desiccation tolerance at a late developmental stage. We uncover unique proteome and metabolic state changes in Aedes embryos during desiccation that reflect reduced central carbon metabolism, rewiring towards polyamine production, and enhanced lipid utilisation for energy and polyamine synthesis. Using inhibitors targeting these processes in blood-fed mosquitoes that lay eggs, we infer a two-step process of desiccation tolerance in Aedes eggs. The metabolic rewiring towards lipid breakdown and dependent polyamine accumulation confers resistance to desiccation. Furthermore, rapid lipid breakdown is required to fuel energetic requirements upon water reentry to enable larval hatching and survival upon rehydration. This study is fundamental to understanding Aedes embryo survival and in controlling the spread of these mosquitoes.

Abstract Background Type 1 diabetes (T1D) is an autoimmune disease that is increasing in prevalence worldwide. One of the contributing factors to the pathogenesis of T1D is the composition of the intestinal microbiota, as has been demonstrated. in T1D patients, with some studies demonstrating a deficiency in their levels of Prevotella. We have isolated a strain of Prevotella histicola from a duodenal biopsy that has anti-inflammatory properties, and in addition, alters the development of autoimmune diseases in mouse models. Therefore, our hypothesis is that the oral administration of P. histicola might delay the development of T1D in the non-obese diabetic (NOD) mice. To assess this, we used the following materials and methods. Female NOD mice (ages 5–8 weeks) were administered every other day P. histicola that was cultured in-house. Blood glucose levels were measured every other week. Mice were sacrificed at various time points for histopathological analysis of the pancreas. Modulation of immune response by the commensal was tested by analyzing regulatory T-cells and NKp46+ cells using flow cytometry and intestinal cytokine mRNA transcript levels using quantitative RT-PCR. For microbial composition, 16 s rRNA gene analysis was conducted on stool samples collected at various time points. Results Administration of P. histicola in NOD mice delayed the onset of T1D. Beta diversity in the fecal microbiomes demonstrated that the microbial composition of the mice administered P. histicola was different from those that were not treated. Treatment with P. histicola led to a significant increase in regulatory T cells with a concomitant decrease in NKp46+ cells in the pancreatic lymph nodes as compared to the untreated group after 5 weeks of treatment. Conclusions These observations suggest that P. histicola treatment delayed onset of diabetes by increasing the levels of regulatory T cells in the pancreatic lymph nodes. This preliminary work supports the rationale that enteral exposure to a non pathogenic commensal P. histicola be tested as a future therapy for T1D.

AbstractThe Ataxin-2 (Atx2) protein contributes to the progression of neurodegenerative phenotypes in animal models of amyotrophic lateral sclerosis (ALS), type 2 spinocerebellar ataxia (SCA-2), Parkinson’s disease, and Huntington’s disease (HD). However, because the Atx2 protein contains multiple separable activities, deeper understanding requires experiments to address the exact mechanisms by which Atx2 modulates neurodegeneration (ND) progression. Recent work on two ALS models, C9ORF72 and FUS, in DrosophilaDrosophila

Dunaliella salina has been widely reported in the halophilic environment. The present study first time reveals and reports the presence of green alga D. salina identified by both morphological and molecular identification from Andaman and Nicobar Islands, a rainy tropical environment. Besides, it was adapted for the optimization of total carotenoid production by using Taguchi tool with various combinations of different parameters, like light intensity, pH, salinity, NaNO3 and NaH2PO4 in basal De Walne’s medium of which 40µEm-2s-1 light intensity showed maximum production of 249.24 µg/mL of total carotenoid followed by NaNO3, NaH2PO4, pH, and salinity. Hence, this study proves that D. salina possesses the character of adapting to the extreme habitats with total carotenoid production.

Bacterial therapeutics are the emergent alternatives in treating autoimmune diseases such as Rheumatoid Arthritis [RA]. P. histicola MCI 001 is one such therapeutic bacterium that has been proven to treat autoimmune diseases such as RA and multiple sclerosis [MS] in animal models. The present study characterized P. histicola MCI 001 isolated from a human duodenal biopsy, and evaluated its impact on the gut microbial and metabolic profile in a longitudinal study using the collagen-induced arthritis model in HLA-DQ8.AEo transgenic mice. P. histicola MCI 001 though closely related to the type strain of P. histicola, DSM 19854, differed in utilizing glycerol. In culture, P. histicola MCI 001 produced vitamins such as biotin and folate, and was involved in digesting complex carbohydrates and production of acetate. Colonization study showed that duodenum was the predominant niche for the gavaged MCI 001. A longitudinal follow-up of gut microbial profile in arthritic mice treated with MCI 001 suggested that dysbiosis caused due to arthritis was partially restored to the profile of naïve mice after treatment. A taxon-level analysis suggested an expansion of intestinal genus Allobaculum in MCI001 treated arthritic mice. Eubiosis achieved post treatment with P. histicola MCI 001 was also reflected in the increased production of short-chain fatty acids [SCFAs]. Present study suggests that the treatment with P. histicola MCI 001 leads to an expansion of Allobaculum by increasing the availability of simple carbohydrates and acetate. Restoration of microbial profile and metabolites like butyrate induce immune and gut homeostasis.

The gastrointestinal pathologies have increased over the last years. The clinical pictures of inflammatory and irritable bowel disease might overlap, leading to expensive and invasive tests. Our study aims to investigate fecal calprotectin as an effective tool for differential diagnosis of gastrointestinal disorders. Two hundred fifty-six patients with the diagnosis of the gastrointestinal disorder and subjected to colonoscopy were collected for the statistical analysis of fecal calprotectin. The differential diagnosis of intestinal inflammation or non-inflammation was performed according to the Receiver Operating Characteristic (ROC) curve that outlines the Area Under Curve (AUC), Sensitivity (Se), Specificity (Sp). Fecal calprotectin was significantly elevated in patients with inflammatory bowel disease compared with patients with irritable bowel syndrome. Especially, the mean values of fecal calprotectin were 522 mg/g (IQR=215-975) and 21 mg/g (IQR=14-34.5) in patients with and without inflammation, respectively (P

Ataxin-2 (Atx2) is a translational control molecule mutated in spinocerebellar ataxia type II and amyotrophic lateral sclerosis. While intrinsically disordered domains (IDRs) of Atx2 facilitate mRNP condensation into granules, how IDRs work with structured domains to enable positive and negative regulation of target mRNAs remains unclear. Using the Targets of RNA-Binding Proteins Identified by Editing technology, we identified an extensive data set of Atx2-target mRNAs in the Drosophila brain and S2 cells. Atx2 interactions with AU-rich elements in 3′UTRs appear to modulate stability/turnover of a large fraction of these target mRNAs. Further genomic and cell biological analyses of Atx2 domain deletions demonstrate that Atx2 (1) interacts closely with target mRNAs within mRNP granules, (2) contains distinct protein domains that drive or oppose RNP-granule assembly, and (3) has additional essential roles outside of mRNP granules. These findings increase the understanding of neuronal translational control mechanisms and inform strategies for Atx2-based interventions under development for neurodegenerative disease.

Obesity is a growing worldwide problem that generally starts in the early years of life and affects minorities more often than Whites. Thus, there is an urgency to determine factors that can be used as targets as indicators of obesity. In this study, we attempt to generate a profile of gut and oral microbial clades predictive of disease status in African American (AA) and European American (EA) children. 16S rDNA sequencing of the gut and saliva microbial profiles were correlated with salivary amylase, socioeconomic factors (e.g., education and family income), and obesity in both ethnic populations. Gut and oral microbial diversity between AA and EA children showed significant differences in alpha-, beta-, and taxa-level diversity. While gut microbial diversity between obese and non-obese was not evident in EA children, the abundance of gut Klebsiella and Magasphaera was associated with obesity in AA children. In contrast, an abundance of oral Aggregatibacter and Eikenella in obese EA children was observed. These observations suggest an ethnicity-specific association with gut and oral microbial profiles. Socioeconomic factors influenced microbiota in obesity, which were ethnicity dependent, suggesting that specific approaches to confront obesity are required for both populations.

Rheumatoid arthritis (RA) is an autoimmune disorder with multifactorial etiology; both genetic and environmental factors are known to be involved in pathogenesis. Treatment with disease-modifying antirheumatic drugs (DMARDs) plays an essential role in controlling disease progression and symptoms. DMARDs have immunomodulatory properties and suppress immune response by interfering in various pro-inflammatory pathways. Recent evidence has shown that the gut microbiota directly and indirectly modulates the host immune system. RA has been associated with dysbiosis of the gut microbiota. Patients with RA treated with DMARDs show partial restoration of eubiotic gut microbiome. Hence, it is essential to understand the impact of DMARDs on the microbial composition and its consequent influences on the host immune system to identify novel therapies for RA. In this review, we discuss the importance of antirheumatic-drug-induced host microbiota modulations and possible probiotics that can generate eubiosis.

Objective: To identify a potential bacterium which produces antimicrobial peptide (vibriocin), and its purification, characterization and production optimization. The bacteria subjected in the study were isolated from a highly competitive ecological niche of mangrove ecosystem. Methods: The bacterium was characterized by phenotype besides 16S rRNA gene sequence analysis. The antibacterial activity was recognised by using agar well diffusion method. The vibriocin was purified using ammonium sulphate precipitation, butanol extraction, gel filtration chromatography, ion-exchange chromatography and subsequently, by HPLC. Molecular weight of the substance identified in SDS-PAGE. Production optimization performed according to Taguchi's mathematical model using 6 different nutritional parameters as variables. Results: The objective bacterium was identified as Vibrio parahaemolyticus. The vibriocin showed 18 KDa of molecular mass with mono peptide in nature and highest activity against pathogenic Vibrio harveyi. The peptide act stable in a wide range of pH, temperature, UV radiation, solvents and chemicals utilized. An overall ~20% of vibriocin production was improved, and was noticed that NaCl and agitation speed played a vital role in secretion of vibriocin. Conclusions: The vibriocin identified here would be an effective alternative for chemically synthesized drugs for the management of Vibrio infections in mariculture industry.

The notion that decapping leads irreversibly to messenger RNA (mRNA) decay was contradicted by the identification of capped transcripts missing portions of their 5′ ends and a cytoplasmic complex that can restore the cap on uncapped mRNAs. In this study, we used accumulation of uncapped transcripts in cells inhibited for cytoplasmic capping to identify the targets of this pathway. Inhibition of cytoplasmic capping results in the destabilization of some transcripts and the redistribution of others from polysomes to nontranslating messenger ribonucleoproteins, where they accumulate in an uncapped state. Only a portion of the mRNA transcriptome is affected by cytoplasmic capping, and its targets encode proteins involved in nucleotide binding, RNA and protein localization, and the mitotic cell cycle. The 3′ untranslated regions of recapping targets are enriched for AU-rich elements and microRNA binding sites, both of which function in cap-dependent mRNA silencing. These findings identify a cyclical process of decapping and recapping that we term cap homeostasis.

Cytoplasmic capping is catalyzed by a complex that contains capping enzyme (CE) and a kinase that converts RNA with a 5'-monophosphate end to a 5' diphosphate for subsequent addition of guanylic acid (GMP). We identify the proline-rich C-terminus as a new domain of CE that is required for its participation in cytoplasmic capping, and show the cytoplasmic capping complex assembles on Nck1, an adapter protein with functions in translation and tyrosine kinase signaling. Binding is specific to Nck1 and is independent of RNA. We show by sedimentation and gel filtration that Nck1 and CE are together in a larger complex, that the complex can assemble in vitro on recombinant Nck1, and Nck1 knockdown disrupts the integrity of the complex. CE and the 5' kinase are juxtaposed by binding to the adjacent domains of Nck1, and cap homeostasis is inhibited by Nck1 with inactivating mutations in each of these domains. These results identify a new domain of CE that is specific to its function in cytoplasmic capping, and a new role for Nck1 in regulating gene expression through its role as the scaffold for assembly of the cytoplasmic capping complex.