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Bacillus subtilis, a probiotic bacterium with engineering potential, is widely used for the expression of exogenous proteins. In this study, we utilized the integrative plasmid pDG364 to integrate the hemagglutinin–neuraminidase (HN) gene from Newcastle disease virus (NDV) into the genome of the B. subtilis 168 model strain. We successfully constructed a recombinant B. subtilis strain (designated B. subtilis RH) that displays a truncated HN antigen fragment on the surface of its spores and further evaluated its immunogenic effects in mice. Using ELISA, we quantified the levels of IgG in serum and secretory IgA (sIgA) in intestinal contents. The results revealed that the recombinant B. subtilis RH elicited robust specific mucosal and humoral immune responses in mice. Furthermore, B. subtilis RH demonstrated potential mucosal immune adjuvant properties by fostering the development of immune organs and augmenting the number of lymphocytes in the small intestinal villi. Additionally, the strain significantly upregulated the relative expression of inflammatory cytokines such as IL-1β, IL-6, IL-10, TNF-α, and IFN-γ in the small intestinal mucosa. In conclusion, the B. subtilis RH strain developed in this study exhibits promising mucosal immunogenic effects. It holds potential as a candidate for an anti-NDV mucosal subunit vaccine and offers a novel preventive strategy for the poultry industry against this disease. [ABSTRACT FROM AUTHOR]

We examine the problem of planning the supply of rewards in coalition loyalty programmes considering that the buyer–supplier relationships with commercial partners are governed by option contracts rather than wholesale price contracts similar to what is commonly used in practice. We develop a two-stage stochastic linear programme model with simple recourse which considers uncertain demand requirements, limited reward purchasing budgets, multiple programme partners of various sizes, point-liability control targets and overall profitability. A sampling average approximation scheme is used to solve the model. Numerical experiments show that option contracts perform better than wholesale price contracts when redemption demand uncertainty is high and the number of redemption partners is large. The results also suggest that the common practice of increasing redemption capacities is not the most effective way to cope with demand uncertainties. Programmes that reduce redemption demand variability and/or create better contracting structures are more promising in improving points-liability, redemption budget spending and overall profitability than traditional approaches. [ABSTRACT FROM PUBLISHER]

Brevibacillus laterosporus is a strain of probiotic bacteria that has been widely used in pest control, cash crop, and other production areas. However, few studies have been conducted on its use as a feed additive in animals. Therefore, the probiotic potential of B. laterosporus PBC01 was evaluated by characterizing hydrophobicity, auto-aggregation activity, bile salt and simulated gastrointestinal fluid tolerance, bienzymatic, and antibacterial activity. Antibiotic susceptibility, hemolysis assays, and supplemental feeding of mice were also performed to evaluate safety features. Our results showed that B. laterosporus PBC01 had moderate hydrophobicity, high auto-agglutination ability. Meanwhile, B. laterosporus PBC01 had good tolerance to bile salt and simulated gastrointestinal fluid. It had the ability to secrete protease, cellulase, and to inhibit various pathogens. In addition, B. laterosporus PBC01 was sensitive to many antibiotics, and did not produce hemolysin. In the safety assessment of mice, it did not cause any deaths, nor did it affect the cell components of blood, antioxidant capacity, and reproductive health. The study indicated the great probiotic characteristics and safety of B. laterosporus PBC01. This may provide a theoretical basis for the clinical application and development of probiotic-based feed additives., (© 2024 Federation of American Societies for Experimental Biology.)

Controllable regulation of stem cell differentiation is a critical concern in stem cell-based regenerative medicine. In particular, there are still great challenges in controlling the directional differentiation of neural stem cells (NSCs) into neurons. Herein, we developed a novel linear-branched poly( β -amino esters) (S4-TMPTA-BDA-DT, STBD) through a two-step reaction. The synthesized linear-branched polymers possess multiple positively charged amine terminus and degradable intermolecular ester bonds, thus endowing them with excellent properties such as high gene load, efficient gene delivery, and effective gene release and transcription in cells. In the mCherry transfection test, a high transfection efficiency of approximately 70% was achieved in primary NSCs after a single transfection. Moreover, STBD also showed high biocompatibility to NSCs without disturbing their viability and neural differentiation. With the high gene delivery property, STBD is capable of delivering siRNA (shSOX9) expression plasmid into NSCs to significantly interfere with the expression of SOX9, thus enhancing the neuronal differentiation and maturation of NSCs. The STBD/DNA nano-polyplex represents a powerful non-viral approach of gene delivery for manipulating the differentiation of stem cells, showing broad application prospects in NSC-based regenerative therapy for treating neurodegenerative diseases., (© 2022 IOP Publishing Ltd.)