Objective: The purpose of this study is to investigate the therapeutic effects of exosomes that overexpress miR-126-3p on cisplatin-induced premature ovarian failure (POF) in rats.Methods: Forty-five specific pathogen-free female Wistar rats were randomly divided into three groups of 15 rats each (NC, POF, and EXO). The NC group received intraperitoneal injections of an equivalent volume of normal saline, while the POF and EXO groups were injected with cisplatin (1 mg/kg, dissolved in normal saline) for 14 consecutive days to establish a POF model in rats. Lentiviral vectors overexpressing miR-126-3p were used to transfect human adipose-derived mesenchymal stem cells. Then, the resulting exosomes were prepared for use. After the POF model was successfully established, the NC and POF groups were injected with PBS, and the EXO group received tail vein injections of ADSCs-EXO-miR-126-3p. Changes in body weight and serum hormone levels (AMH, FSH, and E2) were observed at 0, 1, 2, 3, and 4 weeks post-modeling, alongside histopathological changes.Results: Human adipose-derived mesenchymal stem cells were successfully isolated, and exosomes that overexpress miR-126-3p were obtained (P<0.01). After modeling, the POF group showed the following changes compared to the NC group: a significant decrease in body weight, a marked reduction in ovarian weight (P<0.01), and significantly lower levels of AMH(P<0.001) and E2(P<0.000 1); a significant increase in FSH(P<0.001); a significant decrease in miR-126-3p expression (P<0.05); HE staining revealed a significant reduction in follicle number of follicles in the POF group; and the mating test showed a significant decrease in offspring production (P<0.01). Treatment with ADSCs-EXO-miR-126-3p revealed that the body weight of the EXO group gradually increased beyond that of the POF group, though it remained below that of the NC group. AMH and E2 levels initially decreased in the EXO group and then gradually increased beyond those in the POF group, reaching the hormone levels of the NC group. FSH levels initially increased in the EXO group and then gradually decreased below those of the POF group, reaching the hormone levels similar to those of the NC group. Compared to the POF group, the EXO group showed a significant increase in ovarian weight (P<0.01), though there was no significant difference compared to the NC group. The expression of miR-126-3p significantly increased (P<0.001), and there was no significant difference from the NC group. HE staining results indicated that the number of follicles in the EXO group increased significantly compared to the POF group, approaching normal levels. The mating test results revealed a significant increase in offspring production for the EXO group compared to the POF group (P<0.000 1), though there was no significant difference between the EXO and NC groups.Conclusion: ADSCs-EXO-miR-126-3p can improve ovarian function, restore hormone levels, and significantly increase fertility, while reducing infertility.

Objective: This study aims to clarify the biological characteristics of the antibacterial peptide BSN-25 and to develop a lactate expression system for the USP₄₅+BSN-25 fusion protein. Methods: First, the minimum inhibitory concentrations (MICs) of BSN-25 for the Salmonella typhimurium and Escherichia coli strains were tested by the two-fold dilution method. The hemolysis rates of BSN-25 against red blood cells, as well as its toxicity against IPEC-J2 cells, were determined. Second, the sequence of usp45+bsn-25 was amplified by PCR walking and then, the recombined plasmid containing the hybrid sequence was constructed. The USP₄₅+BSN-25 fusion protein, produced by the NZ9000 pNZ8148 6×His SP_USP45-11∷ usp45+ bsn-25, was identified by Western blot. Moreover, its expression conditions were optimized. The USP₄₅+BSN-25 was obtained and digested by enterokinase in vitro and its antibacterial activity against S. typhimurium was tested using the agar diffusion method and the two-fold dilution method. Results: The MICs of BSN-25 against 10 isolates of multidrug-resistant (MDR) S. typhimurium and E. coli range from 3.13 μg/mL to 6.25 μg/mL. BSN-25 did not exhibit hemolytic activity against red blood cells or toxicity against IPEC-J2 cells. The engineered strain can secret USP₄₅+BSN-25, and the highest amount was produced when the strain was induced by 2.5 ng/mL of nisin at 26℃ for 6 h without shaking. Enterokinase digestion of the protein USP₄₅+BSN-25 in vitro revealed its antibacterial activity against S. typhimurium CVCC541. Conclusion: The BSN-25 compound exhibits strong antibacterial activity against MDR S. typhimurium and E.coli. Moreover, it exhibits no hemolysis of red blood cells and is non-toxic to eukaryotic cells. The constructed lactate genetic engineering strain can secret USP₄₅+BSN-25, which exhibits antibacterial activity following digestion by enterokinase.

Although α-amino acid ester acyltransferase (Aet) efficiently and selectively catalyzes the synthesis of Ala-Gln, its limited stability constrains its application in biocatalysis. To address this issue, Aet from Sphingobacterium siyangensis AJ2458 was immobilized in this study. After screening immobilization materials, nanoflowers were selected for enzyme encapsulation. Then, the embedding time, composition ratios, and optimal reaction conditions were systematically optimized. The immobilized enzyme was further characterized and evaluated for its morphology, stability, and reusability. The results demonstrated that nanoflowers synthesized using 40 mmol/L PBS (pH 7.4), 200 mmol/L CuSO₄, and 0.55 mg of the enzyme [Aet @(Cu)₃(PO₄)₂] exhibited a well-defined structure. The optimal temperature and pH for the immobilized enzyme were 25℃ and 8.5, respectively, with significantly enhanced stability compared to the free enzyme. The immobilized enzyme exhibited a specific activity of 4 689.00 U/mg, a 1.68-fold increase over the free enzyme (2 794.64 U/mg), while the Ala-Gln yield increased to 71.24 mmol/L, a 67.86% increase over the free enzyme (42.44 mmol/L). Even after 10 reuse cycles, the enzymatic activity remained above 75% of its initial value. In summary, nanoflower immobilization not only significantly enhanced Aet's stability and catalytic efficiency, but also enabled reusable enzymes and facilitated the rapid separation of enzymes from products demonstrating its strong potential for industrial applications.

Objective: Delivering large functional proteins into mammalian cells and mice remains a persistent challenge in molecular biology. Conventional approaches, including adeno-associated virus (AAV) vectors and direct protein transduction, face limitations in efficiency and specificity. To address this problem, a split intein-mediated protein trans-splicing platform was developed to functionally reconstitute the 220 kDa Dicer ribonuclease Ⅲ. This approach leverages the self-processing property of inteins to precisely ligate two protein fragments, circumventing the challenges of delivering large genes or proteins. Methods: The Dicer gene was strategically truncated into N-terminal (N-segment) and C-terminal (C-segment) fragments at candidate sites (positions 756, 955, and 1 038). The N-segment was connected to the N-terminal split intein (Npu DnaEN), and the C-segment was connected to the C-terminal intein (Npu DnaEC). Each was cloned into a separate mammalian expression plasmid under the control of a CMV promoter. Plasmid pairs were either co-transfected into MLFs or delivered systemically to C57BL/6 mice via intravenous injection. Protein reconstitution was quantified by Western blot using anti-Flag (N-terminal) and anti-HA (C-terminal) antibodies to verify trans-splicing efficiency. Functional validation included cleavage activity and antiviral activity. Results: The truncation site at position 756 was successfully identified, resulting in the production of Npu-Dicer, which exhibits cleavage activity and antiviral efficacy equivalent to that of native Dicer. Western blot analysis confirmed the successful reconstitution of the full-length Dicer protein in MLFs and mouse spleen tissue. Northern blot analysis revealed the generation of siRNA and miRNA in in cells expressing Npu-Dicer, with band intensity matching that of the full-length Dicer control. Conclusion: The trans-splicing capability of Npu DnaE split inteins was harnessed to successfully express the Dicer protein in both MLFs and C57BL/6 mice. The Npu-Dicer-756 demonstrated enzymatic activity and antiviral efficacy similar to that of native Dicer. This establishes Npu-DnaE as a versatile tool for delivering exogenous proteins.

Clustered regularly interspaced short palindromic repeats (CRISPR) is a genome-editing technology that has revolutionized genetic engineering thanks to its exceptional precision and operational simplicity. Induced pluripotent stem cells (iPSCs), characterized by their unlimited self-renewal capacity, multilineage differentiation potential, and ethical compatibility, have emerged as a transformative platform for disease modeling, drug discovery, and regenerative therapies. Integrating iPSCs, which provide a stable human-derived cellular resource for investigating disease mechanisms and developing personalized treatments, with CRISPR-mediated genome manipulation capabilities effectively addresses the limitations of conventional disease models arising from interspecies divergence and genetic heterogeneity. This convergence of synergistic efforts has catalyzed unprecedented progress in both regenerative medicine and pathophysiological research. This review systematically examines the technical principles and evolutionary trajectory of CRISPR systems. It then provides an in-depth analysis of three critical applications that arise from the combination of CRISPR and iPSC technologies: the regulation of cellular differentiation networks, the construction of disease models, and the development of genetically engineered cell-based therapies. Meanwhile, the technical challenges and biological risks associated with this integrated approach are critically evaluated to provide a comprehensive perspective on current advancements and future directions.

Biological 3D printing technology generally is an advanced technique that precisely directs the deposition of biological materials, such as hydrogels, biomolecules, and living cells using computer-aided methods. It is used to construct complex, three-dimensional biomimetic tissues. In recent years, biological 3D printing technology has gained widespread attention in the field of cell sensors. The combination of 3D printing and cell sensors not only effectively avoids errors caused by traditional cell-modified electrodes, but also enables the mass production of three-dimensional biomimetic micro-tissue sensing interfaces. This promotes the transition of sensing mechanisms from the single-cell level to the complex tissue level, achieving technological innovation. This paper begins with the basic concepts and operational principles of cell sensors and biological 3D printing, and then analyzes the characteristics and research value of cell sensors, as well as the current issues. It introduces the advantages, different classification methods, and applications of biological 3D printing technology, with a focus on the key technologies involved in applying biological 3D printing to cell sensors, such as bio-ink preparation, cell scaffold structure design, and three-dimensional cell culture. The latest research progress on biological 3D printing technology for cell sensors is presented. Finally, this paper discusses the challenges and opportunities of using biological 3D printing technology to develoop cell sensors.

Field-effect transistor (FET) biosensors have emerged as a prominent research direction in biomarker detection due to their rapid response characteristics, miniaturization advantages, and high-throughput detection potential. The multidimensional synergies between nanomaterials' unique physicochemical properties and microelectronics/biosensing technologies have laid the foundation for breakthroughs in the performance of FET sensors in medical diagnostics and environmental monitoring. This review investigates the fundamental architecture and operating principles of FET biosensors. It provides a systematic summary of recent advancements in 0D, 1D, 2D, and 3D nanomaterial-based FET biosensors, and elucidates cutting-edge innovations, such as flexible wearable sensing, single-molecule detection, and machine learning-assisted optimization. Furthermore, it discusses prospective trends and challenges over the next five years, providing critical insights for developing next-generation biosensing systems with high-precision performance and multi-scenario compatibility.

Swine leukocyte antigen (SLA) class I molecules play a crucial role in the cellular immune response. These molecules primarily present cytotoxic T leukocyte (CTL) epitopes to CTLs, inducing a cellular response. This process allows CTLs to identify and destroy virus-infected target cells, thereby eliminating the infected virus particles within the host cells. The highly polymorphic structure of SLA-I molecules is pivotal for presenting a diverse range of antigenic peptides. The antigen-presentation mechanism of SLA-I molecules is highly sophisticated. The peptide-binding groove (PBG), which is formed by the α1 and α2 domains of the SLA-I molecules, determines the specificity of the antigenic epitopes. Short peptides bind to SLA-I molecules through hydrogen bonding, electrostatic interactions, and van der Waals forces. The PBG determines which antigenic peptides can be presented to CTLs, thereby influencing the specificity of the immune response. SLA-I molecules can not only present endogenous antigens through the classical presentation pathway, but also present exogenous antigens through the cross-presentation pathway. Given the importance of this mechanism, researchers have been working to establish functional antigenic epitope screening systems based on SLA-I molecules. The goal of these systems is to identify and characterize epitopes that effectively bind to MHC-I or SLA-I molecules in order to activate CTLs and to induce a robust immune response. In recent years, significant progress has been made in the field of epitope screening. Thanks to advances in molecular biology, bioinformatics, and immunology, researchers have developed more accurate and efficient methods for identifying and characterizing antigenic epitopes. These methods include computational modeling and experimental validation. Computer simulations are used to predict antigenic epitopes based on the sequences and structures of antigenic proteins and major histocompatibility complexes using homology or comparative modeling. First, structure models are formed and then, molecular docking simulations are carried out. Next, characterization and analysis of antigenicity and homology are performed. Although epitope prediction algorithms can improve screening efficiency, the accuracy of the prediction results must still be determined through experimental validation. Methods for experimentally validating CTL epitopes include tetramer techniques, in vitro binding techniques, and animal experiments. Research has continuously expanded our understanding of the function of SLA-I molecules, especially with regard to their roles in antigen presentation and immune activation. This is based on the characteristics of SLA-I molecules' structure and function, especially their antigen-presenting mechanisms. Recently, significant progress has been made in antigenic epitope screening, which has also enhanced our understanding of the function of SLA-I. In this review, the structure and function of SLA-I molecules are discussed, and the new progress made in antigenic epitope screening is summarized. This knowledge is essential for developing epitope vaccines derived from swine viruses. Understanding the specific interactions between SLA-I molecules and antigenic peptides allows researchers to design vaccines that elicit strong, specific immune responses. This could potentially improve the efficacy of vaccines against viral diseases of swine origin. This review will provide valuable insights into the structure and function of SLA-I molecules and the mechanisms of SLA-I restricted CTL epitopes, which is crucial for developing epitope vaccines for important swine-origin viruses.

As an important model organism, Saccharomyces cerevisiae has played a key role in aging research. Thanks to continuous advancements in gene editing technologies, yeast provides a reliable experimental platform for studying aging mechanisms and serves as an essential tool for screening and validating anti-aging strategies. The application of yeast in anti-aging research has expanded to include drug screening and functional food development. This has lead to significant progress, especially in discovering natural anti-aging compounds and regulating aging pathways. This review summarizes the latest advancements in using yeast as a model organism for anti-aging research. It also discusses the potential of using yeast to explore aging mechanisms and anti-aging applications, as well as future research directions.

Biogenic amines are nitrogen-containing, low molecular weight organic compounds that are widely distributed in fermented foods and certain natural foods. They have various physiological regulatory functions, such as influencing neural activity and immune responses. However, if ingested in excess, biogenic amines may cause adverse health effects such as headaches, nausea, allergic reactions, and cardiovascular disease. Therefore, controlling their levels is essential for ensuring food safety. Multicopper oxidases (MCOs) can oxidize biogenic amines to produce the corresponding aldehyde, ammonia, and water, and thus shows great potential for decomposing biogenic amines. They are mainly used to degrade toxic biogenic amines in food products, thereby enhancing food safety. However, MCOs still face challenges in practical applications, such as low catalytic efficiency, poor enzyme stability, insufficient degradation rate and low enzyme production by strains, which limits their widespread application in the fermented food industry. In recent years, progress has been made to address the above problems through molecular modification and recombinant expression of MCOs. This has improved the catalytic performance and stability of MCOs, and optimized the expression system to enhance its enzyme activity and yield. These technical means can improve the catalytic efficiency, degradation ability, and application stability of MCOs, enabling its better application in the food industry. This paper reviews the molecular modification and recombinant expression of MCO, a key enzyme in the degradation of biogenic amines. It also explains the great potential application of MCOs in controlling the safety of fermented foods.

This paper traces the development of the European Union (EU)'s bioeconomy strategy from a fragmented framework to a mature and integrated policy system. It analyzes how the EU coordinates bioeconomic development with non-traditional security objectives using a three-dimensional governance model. This model involves the European Commission setting the agenda, member states implementing it, and technical agencies deeply engaging. This integrated system encompasses policy frameworks, institutional coordination, financial support mechanisms, and risk regulation. The strategy has increased the EU's efficiency in food production, capacity in climate governance, and energy independence. However, challenges remain, including insufficient policy alignment among member states, fragmented security governance, increasing protectionism, and the influence of right-wing political forces. Drawing from the EU experience, this paper suggests that China should proactively develop a comprehensive legal framework and bolster cross-sectoral coordination to advance bioeconomic development in tandem with national security objectives.

As an important issue affecting human social life and security, the concept of biosafety has been in a state of dynamic evolution, which makes biosafety governance difficult. Japan is one of the first countries to participate in global biosecurity governance. Over time, it has developed a multi-level governance system for different biosecurity issues. On an individual level, it focuses on shaping biosecurity norms and crisis awareness, and strengthens awareness of biosecurity threats. On a social level, it emphasizes the coordinated participation of multiple actors, and addresses sudden biosecurity crises through “official-civilian collaboration.” At a national level, the focus is on the coordinated cooperation between relevant government departments. The goal is to build a “control tower” response system centered on crisis management to enhance the ability to respond to biosecurity crises. As an important part of China's national security, biosafety governance issues should be examined from the individual, social and national levels under the guidance of the overall national security concept. To enhance China's biosecurity governance capabilities and strengthen its discourse power in global biosecurity governance, China should continue to strengthen biosecurity education, improve the construction of biosecurity laws and regulations, and improve collaborative governance mechanisms involving multiple stakeholders.