In Situ Synthesis of an Immune-Checkpoint Blocker from Engineered Bacteria Elicits a Potent Antitumor Response.

Immune-checkpoint blockade (ICB) reinvigorates T cells from exhaustion and potentiates T-cell responses to tumors. However, most patients do not respond to ICB therapy, and only a limited response can be achieved in a "cold" tumor with few infiltrated lymphocytes. Synthetic biology can be used to engineer bacteria as controllable bioreactors to synthesize biotherapeutics in situ. We engineered attenuated Salmonella VNP20009 with synthetic gene circuits to produce PD-1 and Tim-3 scFv to block immunosuppressive receptors on exhausted T cells to reinvigorate their antitumor response. Secreted PD-1 and Tim-3 scFv bound PD-1+ Tim-3+ T cells through their targeting receptors in vitro and potentiated the T-cell secretion of IFN-γ. Engineered bacteria colonized the hypoxic core of the tumor and synthesized PD-1 and Tim-3 scFv in situ, reviving CD4+ T cells and CD8+ T cells to execute an antitumor response. The bacteria also triggered a strong innate immune response, which stimulated the expansion of IFN-γ+ CD4+ T cells within the tumors to induce direct and indirect antitumor immunity.

Cognitive-behavioral therapy for patients with somatoform disorders: A pilot preliminary randomized controlled trial.

Background and objective: Cognitive-behavioral therapy (CBT) for somatoform disorders (SFDs) is understudied in China. Western findings may not be applicable to Chinese culture. This preliminary study evaluated the efficacy of CBT for patients in China, relative to treatment-as-usual (TAU). Methods: Seventy patients with SFDs randomly received either combined CBT and TAU (CBT + TAU), or TAU alone between January 2018 to May 2019. The CBT + TAU group received 12 weekly individual 50-minute CBT sessions. Participants were blindly assessed at 4 timepoints (baseline, week 6, end of treatment: week 12; 12 weeks post-treatment: week 24) using the following outcome measures: SQSS (Self-screening Questionnaire for Somatic Symptoms); PHQ-15 (Patient-Health-Questionnaire-15) and the WI (Whiteley Index); GAD-7 (General Anxiety Disorder-7); HAMD-17 (Hamilton Depression Rating Scale-17); Family Burden Interview Schedule (FBIS); Sheehan Disability Scale (SDS); and the Short Form of Quality-of-Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q-SF). The primary endpoint was the difference between the SQSS total score at week 24 and the baseline. A mixed model for repeated measures was used to analyze inter- and intra-group changes from the baseline. Results: At week 24, The least-squares mean (LSM) change of the total score on the SQSS was -18.87 points and -9.69 points, respectively in the CBT + TAU group and in the TAU group (LSM difference, -9.18 points; 95% confidence interval, -15.72 to -2.64; P = 0.0068). At week 24, the LSM changes from baseline in the WI, HAMD, PHQ15, FBIS and SDS total scores were significantly different between the two groups, however, there was no significant difference in the Q-LES-Q-SF. The SQSS of group effect sizes were 0.63 at 24 weeks. The dropout rates of the CBT + TAU and TAU groups were comparable (22.9% and 19.3%). Conclusions: These preliminary findings suggest that CBT may be helpful for improving the symptoms of patients with SFDs in China.

Drug-loaded lipid nanoparticles improve the removal rates of the Staphylococcus aureus biofilm.

Biofilms of the foodborne pathogen Staphylococcus aureus show improved resistance to antibiotics and are difficult to eliminate. To enhance antibacteria and biofilm dispersion via extracellular matrix diffusion, a new lipid nanoparticle was prepared, which employed a mixture of phospholipids and a 0.8% surfactin shell. In the lipid nanoparticle, 31.56 µg mL-1 of erythromycin was encapsulated. The lipid nanoparticle size was approximately 52 nm and the zeta-potential was -67 mV, which was measured using a Marvin laser particle size analyzer. In addition, lipid nanoparticles significantly dispersed the biofilms of S. aureus W1, CICC22942, and CICC 10788 on the surface of stainless steel, reducing the total viable count of bacteria in the biofilms by 103 CFU mL-1 . In addition, the lipid nanoparticle can remove polysaccharides and protein components from the biofilm matrix. The results of laser confocal microscopy showed that the lipid nanoparticles effectively killed residual bacteria in the biofilms. Thus, to thoroughly eliminate biofilms on material surfaces in food factories to avoid repeated contamination, drug-lipid nanoparticles present a suitable method to achieve this.

Prevention of high-fat-diet-induced obesity in mice by soluble dietary fiber from fermented and unfermented millet bran.

Obesity-related diabetes, cardiovascular disease, and hypertension pose many risks to human health. Thus, mice on a high-fat diet were gavaged with millet bran (unfermented/fermented) soluble dietary fiber (RSDF/FSDF, 500 mg·kg-1) for 10 weeks in current research, and then evaluated the various biological indicators. These findings revealed that RSDF and FSDF supplements could prevent fat synthesis by inhibiting sterol regulatory element-binding protein-1c gene expression. The RSDF supplements can also accelerate fat catabolism through enhanced the mRNA expression levels of adipose triglyceride lipase and peroxisome proliferator-activated receptor α. FSDF supplements can prevent obesity by decreasing 3-hydroxy-3-methyl-glutaryl-CoA reductase expression and increasing cholesterol 7α-hydroxylase expression. Moreover, FSDF also controls obesity development by lowering total cholesterol and low-density lipoprotein cholesterol levels in the blood, triglyceride, total cholesterol, and bile acid levels in the liver. Notably, FSDF supplements can promote Bacteroides and Prevotella propagation; excretive propionic acid binds to free fatty acid receptor 2/3 and then stimulates intestinal epithelial cells to generate glucagon-like-peptide-1 and peptide YY, which can reduce food and energy intake and ultimately prevent obesity. All evidence suggests that FSDF supplements play a crucial role in preventing obesity.

Self-cascade deoxynivalenol detoxification by an artificial enzyme with bifunctions of dehydrogenase and aldo/keto reductase from genome mining.

Due to the severe health risks for human and animal caused by the intake of toxic deoxynivalenol (DON) derived from Fusarium species, elimination DON in food and feed has been initiated as a critical issue. Enzymatic cascade catalysis by dehydrogenase and aldo-keto reductase represents a fascinating strategy for DON detoxification. Here, one quinone-dpendent alcohol dehydrogenase DADH oxidized DON into less-toxic 3-keto-DON and NADPH-dependent aldo-keto reductase AKR13B3 reduced 3-keto-DON into relatively non-toxic 3-epi-DON were identified from Devosia strain A6-243, indicating that degradation of DON on C3 are two-step sequential cascade processes. To establish the bifunctions, fusion enzyme linking DADH and AKR13B3 was successfully assembled to promote one-step DON degradations with accelerated specific activity and efficiency, resulting 93.29 % of DON removal rate in wheat sample. Three-dimensional simulation analysis revealed that the bifunctional enzyme forms an artificial intramolecular channel to minimize the distance of intermediate from DADH to AKR13B3 for two-step enzymatic reactions, and thereby accelerates this enzymatic process. As the first report of directing single step DON detoxification by an interesting bifunctional artificial enzyme, this work revealed a facile and eco-friendly approach to detoxify DON with application potential and gave valuable insights into execute other mycotoxin detoxification for ensuring food safety.