Inhalable vaccine of bacterial culture supernatant extract mediates protection against fatal pulmonary anthrax.

Pulmonary anthrax is the most fatal clinical form of anthrax and currently available injectable vaccines do not provide adequate protection against it. Hence, next-generation vaccines that effectively induce immunity against pulmonary anthrax are urgently needed. In the present study, we prepared an attenuated and low protease activity Bacillus anthracis strain A16R-5.1 by deleting five of its extracellular protease activity-associated genes and its lef gene through the CRISPR-Cas9 genome editing system. This mutant strain was then used to formulate a lethal toxin (LeTx)-free culture supernatant extract (CSE) anthrax vaccine, of which half was protective antigen (PA). We generated liquid, powder, and powder reconstituted formulations that could be delivered by aerosolized intratracheal inoculation. All of them induced strong humoral, cellular, and mucosal immune responses. The vaccines also produced LeTx neutralizing antibodies and conferred full protection against the lethal aerosol challenges of B. anthracis Pasteur II spores in mice. Compared to the recombinant PA vaccine, the CSE anthrax vaccine with equal PA content provided superior immunoprotection against pulmonary anthrax. The preceding results suggest that the CSE anthrax vaccine developed herein is suitable and scalable for use in inhalational immunization against pulmonary anthrax.

Controlling CRISPR-Cas9 by guide RNA engineering.

The clustered regularly interspaced short palindromic repeats (CRISPR) system is a product of million years of evolution by microbes to fight against invading genetic materials. Around 10 years ago, scientists started to repurpose the CRISPR as genetic tools by molecular engineering approaches. The guide RNA provides a versatile and unique platform for the innovation to improve and expand the application of CRISPR-Cas9 system. In this review, we will first introduce the basic sequence and structure of guide RNA and its role during the function of CRISPR-Cas9. We will then summarize recent progress on the development of various guide RNA engineering strategies. These strategies have been dedicated to improve the performance of CRISPR-Cas9, to achieve precise spatiotemporal control of CRISPR-Cas9, and to broaden the application of CRISPR-Cas9. Finally, we will briefly discuss the uniqueness and advantage of guide RNA-engineering based systems versus those with engineered Cas9 proteins and speculate potential future directions in guide RNA engineering. This article is categorized under: RNA Methods > RNA Analyses In Vitro and In Silico RNA Methods > RNA Nanotechnology Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes.

Efficacy and safety of high-dose dual therapy for Helicobacter pylori rescue therapy: A systematic review and meta-analysis.

OBJECTIVE: Although some studies have reported >90% success with high-dose dual proton pump inhibitor (PPI)-amoxicillin dual therapy for Helicobacter pylori (H. pylori) eradication, the efficacy of this therapy remains controversial. We aimed to re-evaluate the efficacy and safety of high-dose dual therapy on H. pylori eradication. METHODS: We searched PubMed, the Cochrane Library, and EMBASE for randomized clinical trials (RCTs) evaluating the efficacy of high-dose PPI-amoxicillin dual therapy as the rescue therapy on H. pylori eradication. Treatment effect was determined with a fixed-effect model using the inverse variance method and was expressed as risk ratio (RR) with 95% confidence interval (CI). RESULTS: Because of significant statistical heterogeneity (χ2  15.98, I2  = 69%) among the six studies that qualified, four RCTs that included 473 patients with H. pylori infection after eradication failure were assessed. The meta-analysis showed that high-dose dual therapy and guideline-recommended rescue therapies achieved similar efficacy (81.3% vs 81.5%, RR 1.00 [95% CI 0.93-1.08], intention-to-treat analysis), compliance (95.3% vs 95.4%, RR 1.00 [95% CI 0.97-1.03]), and side effects (17.9% vs 19.7%, RR 0.88 [95% CI 0.62-1.25]). CONCLUSIONS: High-dose PPI-amoxicillin dual therapy is comparable to recommended rescue therapies for H. pylori infection. More researches are needed to determine the efficacy of high-dose dual therapy as a first-line therapy.

Heat Shock Factor Genes of Tall Fescue and Perennial Ryegrass in Response to Temperature Stress by RNA-Seq Analysis.

Heat shock factors (Hsfs) are important regulators of stress-response in plants. However, our understanding of Hsf genes and their responses to temperature stresses in two Pooideae cool-season grasses, Festuca arundinacea, and Lolium perenne, is limited. Here we conducted comparative transcriptome analyses of plant leaves exposed to heat or cold stress for 10 h. Approximately, 30% and 25% of the genes expressed in the two species showed significant changes under heat and cold stress, respectively, including subsets of Hsfs and their target genes. We uncovered 74 Hsfs in F. arundinacea and 52 Hsfs in L. perenne, and categorized these genes into three subfamilies, HsfA, HsfB, and HsfC based on protein sequence homology to known Hsf members in model organisms. The Hsfs showed a strong response to heat and/or cold stress. The expression of HsfAs was elevated under heat stress, especially in class HsfA2, which exhibited the most dramatic responses. HsfBs were upregulated by the both temperature conditions, and HsfCs mainly showed an increase in expression under cold stress. The target genes of Hsfs, such as heat shock protein (HSP), ascorbate peroxidase (APX), inositol-3-phosphate synthase (IPS), and galactinol synthase (GOLS1), showed strong and unique responses to different stressors. We comprehensively detected Hsfs and their target genes in F. arundinacea and L. perenne, providing a foundation for future gene function studies and genetic engineering to improve stress tolerance in grasses and other crops.

Microinjection of neuropeptide Y into periaqueductal grey produces anti-nociception in rats with mononeuropathy.

The present study was carried out to investigate the effects of neuropeptide Y (NPY) in the midbrain periaqueductal grey (PAG) on the nociceptive modulation in mononeuropathic rats. NPY was microinjected into the PAG. The latency of paw withdrawal (PWL), assessed by the hot-plate (52 ) and the Randall Selitto test, was measured. Intra-PAG administration of 0.05, 0.1 and 0.2 nmol of NPY significantly increased the PWLs in a dose-dependent manner. Co-administration of 0.2 nmol of NPY(28-36) and 5.5 nmol of naloxone significantly attenuated the NPY-induced increase in PWLs. The results suggest that Y(1) receptor may mediate NPY-induced anti-nociception, and that the opioid receptors in PAG may also be involved in this process in mononeuropathic rats.