The bidirectional communication between the gut microbiota (GM) and the enteric nervous system (ENS) is fundamental for gastrointestinal homeostasis. This review dissects the intricate GM–ENS dialogue, emphasizing its transition from a developmental programmer in early life to a sustained regulator of neural plasticity in adulthood. We synthesize the core signaling mechanisms—microbial metabolites, neuroactive substances, and immune mediators—that orchestrate ENS activity. We further propose a multi−timescale model (rapid neuropod/bioelectric, intermediate metabolite, slow immune) with differential relevance to irritable bowel syndrome (IBS) (fast distortions) versus inflammatory bowel disease(IBD)(slow amplification). Critically, we delineate how this axis adopts distinct pathophysiological roles across major digestive disorders: acting as a “signal distorter” in IBS, an “inflammation amplifier” in IBD, and a “tumor accomplice” in colorectal cancer (CRC). By integrating these mechanistic insights with emerging therapeutic paradigms (e.g., precision biomarkers, synthetic microbial consortia, postbiotics), we position the GM–ENS axis as a central hub for understanding disease pathogenesis and a promising framework for developing next-generation precision medicine strategies.

Duck enteritis virus (DEV), a member of the Herpesviridae family, causes an acute and highly contagious disease in waterfowl characterized by vascular injury and severe gastrointestinal lesions. Although DEV infection is known to disrupt cellular homeostasis, the interplay between DEV-induced endoplasmic reticulum (ER) stress and host inflammatory responses in intestinal epithelial cells (IECs) remains poorly understood. We developed an in vitro model using DEV infection in primary duck IECs to study the activation of the unfolded protein response (UPR) and its association with downstream immunomodulatory effects. Our results demonstrated that DEV infection significantly altered ER ultrastructure, characterized by severe rough ER dilation, and triggered ER stress as evidenced by the early upregulation of the chaperone GRP78. Mechanistically, DEV infection was associated with the activation of the PERK-eIF2α-ATF4-CHOP and IRE1α-XBP1 axes of the UPR, while the ATF6 branch showed no significant cleavage under our experimental conditions. Furthermore, activation of the PERK branch was associated with sustained upregulation of the NLRP3 inflammasome and the NF-κB signaling pathway, which correlated with the accumulation of pro-inflammatory cytokines IL-1β and IL-6. Concurrently, the IRE1α branch was associated with the phosphorylation of JNK and the expression of TRAF2, further corresponding to the secretion of IL-1 and TNF-α. Notably, Tunicamycin (Tm)-induced ER stress partially mimicked, but did not fully recapitulate, the robust and sustained inflammatory profile induced by viral infection. These findings suggest a strong correlation between DEV-induced UPR activation and the inflammatory milieu of IECs, providing novel insights into the pathogenesis of DEV-induced enteritis and identifying potential targets for antiviral intervention.

The experiment aimed to explore the gut microbial resources of local chicken breeds and analyze their potential probiotic functional genes, mechanisms, and safety. Using the Anshun Gaojiao chicken as the research object, a heat-tolerant and bile salt-tolerant Bacillus strain was directionally screened. The isolate was preliminarily identified by morphological observation and 16S rDNA gene sequence comparison. Whole-genome sequencing and assembly were performed based on the Illumina HiSeq sequencing platform to systematically analyze its antibacterial spectrum and probiotic potential at the molecular level. The results showed that the isolate was a Gram-positive Bacillus strain as determined by Gram staining microscopy, and named F1. 16S rDNA sequence analysis indicated that the strain F1 shared high homology with Bacillus subtilis AU021 and was located on the same branch of the phylogenetic tree, it was preliminarily identified as Bacillus subtilis. Whole-genome sequencing revealed that strain F1 had a genome size of 4 032 578 bp, a GC content of 44%, and a coding protein gene count of 4 002. Non-Redundant Protein Sequence (NR) database annotation confirmed that F1 belongs to Bacillus subtilis, consistent with the 16S rDNA sequence analysis. Cluster of Orthologous Groups of proteins (COG) database comparison showed that 3 095 protein-coding genes were annotated, included 677 genes with unknown functions. A total of 34 different functional categories were annotated in the Gene Ontology (GO) database. A total of 31 signaling pathways were annotated in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. A comparison of the Carbohydrate-Active enZYmes (CAZy) database revealed that 74 genes were annotated in the strain F1. Comprehensive Antibiotic Resistance Database (CARD) screening identified 11 resistance genes. Virulence Factors Database (VFDB) annotation predicted 7 virulence genes, but no pathogenic toxin genes were detected. Antibiotics & Secondary Metabolite Analysis Shell (antiSMASH) identified 15 gene clusters related to secondary metabolite synthesis. The study shows that Bacillus subtilis F1 possesses certain safety and probiotic potential.

The aim of this study was to investigate the metabolomic changes in the spleens of ducks artificially infected with Clostridium perfringens type A. Twenty-four healthy ducks aged 1 d were used for this purpose. After acclimatization for 37 d, the ducks were divided into 4 treatment groups (n = 6): the control group (normal group), infection Group 1 (66 h), infection Group 2 (90 h) and infection Group 3 (114 h). The ducks in the corresponding infection group were challenged with 8 mL of C. perfringens type A bacterial solution (1 × 108 CFU/mL) for 4 days. The experimental ducks were culled at 0 h, 66 h, 90 h and 114 h after infection, and the ducks were sacrificed for spleen sampling at the end of the experiment. Autopsy observations, spleen pathological changes and pathogen nucleic acid detection were also performed. Finally, the changes in the metabolic profile of the spleen were investigated via a metabolomics approach. At necropsy, the pathological changes in C. perfringens type A infection included enlarged, haemorrhagic and mottled spleens. Histopathology examination revealed that the ducks in the infection group had damaged spleen tissue structures, dilated spleen sinuses with congestion and bleeding, an extreme decrease in lymphocytes, and massive inflammatory cell infiltration in the splenic tissue. Spleen lesions were observed and PCR tests were positive in ducks in the infection group, indicating that a model of C. perfringens type A infection was successfully established in this study. Compared with those in the normal group, 14, 15 and 20 differentially abundant metabolites were identified after 66, 90 and 114 h, respectively, of C. perfringens type A infection of duck spleens, mainly including indolin-2-one, 3-methylindole, 4-hydroxy-2-quinolinecarboxylic acid, indole-3-methyl acetate, uric acid, 2’-deoxyinosine, urate, xanthine, 3-succinoylpyridine, nicotinic acid, phenylacetylglycine, histamine and phosphoenolpyruvate. Pathway analysis revealed that these metabolites were mainly involved in tryptophan metabolism, purine metabolism, nicotinate and nicotinamide metabolism, phenylalanine metabolism, histidine metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, tyrosine metabolism, arginine and proline metabolism, arachidonic acid metabolism, and caffeine metabolism. These findings suggest that C. perfringens type A infection causes a duck spleen inflammatory response and immune response in infected ducks through indolin-2-one, 3-methylindole, 4-hydroxy-2-quinolinecarboxylic acid and tryptophan metabolism, purine metabolism, nicotinic acid and nicotinamide metabolism, which provides a basis for understanding the pathogenesis of C. perfringens type A in ducks.

Inflammatory bowel disease is characterized by severe imbalance of intestinal flora and metabolic disorders. Recent studies have demonstrated that probiotics can effectively alleviate inflammatory bowel disease by restoring the intestinal flora structure and modulating the immune response. However, the role of probiotics in regulating intestinal metabolism disorders is still unclear. This study explores the role of probiotic B. cereus in alleviating DSS-induced colitis. The findings indicated probiotic B. cereus treatment mitigated tissue damage and apoptosis during inflammation. Metabolome and transcriptome analysis revealed B. cereus activated the cholic acid-FXR axis by increasing cholic acid levels, which promoted the gene expression level of NF-κB inhibitor α, reduced the IL-1β, IL-6, IL-18 and TNF-α concentrations. Furthermore, it effectively mitigated the DSS-induced disruption of bile acid metabolism, arginine metabolism, and linoleic acid metabolism. This study explores the effect and mechanisms of probiotic B. cereus on alleviating DSS-induced colitis. It aims to provide a theoretical basis for microbial therapy in inflammatory bowel disease. Significance This study used metabolome and transcriptome to reveal the roles and mechanisms, which probiotic Bacillus cereus modulates metabolic disorders and alleviate DSS-induced colitis. We identified the cholic acid-FXR axis as an important target for alleviating DSS-induced colitis. These findings provide new insights into microbial treatment strategies for IBD.

Avian leukosis virus subgroup J (ALV-J), Reticuloendotheliosis virus (REV), and Chicken infectious anemia virus (CIAV) are important breeder-derived pathogens (BDPs) that continue to threaten poultry health and productivity. These viruses are frequently associated with immunosuppression and coinfections, which complicate eradication efforts, particularly in indigenous chicken breeds. In this study, a TaqMan-based multiplex qPCR (M-qPCR) assay was developed for the simultaneous detection of ALV-J, REV, and CIAV. The assay exhibited excellent linearity (R2 > 0.99), high repeatability (intra-/inter-assay coefficient of variation < 5%), strong specificity with no cross-reactivity against common non-target avian pathogens, and high sensitivity with a detection limit of 10 copies/μL. Moreover, it reliably identified mixed infections even under conditions of unbalanced target concentrations. Parallel testing with commercial singleplex qPCR kits further demonstrated its reliability, yielding concordance rates of 95.8% for ALV-J, 98.3% for REV, and 100% for CIAV. Application of the assay to three local chicken breeds in Guizhou revealed positivity rates of 33.9% (40/118) for ALV-J, 9.3% (11/118) for REV, and 7.6% (9/118) for CIAV, with 20.4% mixed (double and triple) out of all positives. Moreover, serum samples proved more suitable than cloacal swabs for virus detection using the developed M-qPCR assay. In conclusion, the developed M-qPCR assay provides a reliable and efficient tool for surveillance of infections and coinfections in poultry flocks, supporting the prevention and control of BDPs.

The global incidence of colorectal cancer (CRC) is increasing. In the majority of CRC cases, colon cancer develops from alterations in the adenoma-carcinoma sequence pathway. Currently, there are few studies regarding the effects of enteric viruses on the adenoma-carcinoma sequence pathway, and subsequently, the progression and development of the CRC. Here, fecal and tissue samples from a normal control group, an adenomatous polyp group, and a colorectal adenocarcinoma group were collected to gain a deeper understanding of the variations in enteric viruses in CRC patients and to analyze their significance. With the progression of CRC from adenoma to adenocarcinoma, the number of DNA viruses in the virus-like particles (VLPs) of fecal and tissue samples gradually increased, and there were distinct differences in the composition of enteric viruses among the different groups. Multiple species correlation analysis revealed extensive interactions among viruses, bacteria, and fungi in fecal and tissue samples. Functional analysis also revealed that the functional pathways in fecal and tissue samples also underwent significant changes. In conclusion, the changes in the composition and function of enteric viruses in the progression of CRC via adenoma-carcinoma sequence pathway were analyzed in this study, and these changes hold certain importance for exploring the role of enteric viruses in the occurrence of this disease; however, their mode of action and specific mechanisms require further investigation.

Cellulolytic bacteria ferment dietary fiber into short-chain fatty acids, which play an important role in improving fiber utilization and maintaining intestinal health. Safe and effective cellulolytic bacteria are highly promising probiotic candidates. In this study, we isolated three strains of Bacillus cereus, which exhibited cellulolytic properties, from Kele pig feces. To assess the genetic basis of cellulose degradation by the isolates, whole-genome sequencing was used to detect functional genes associated with cellulose metabolism. Subsequently, we identified that the B. cereus CL2 strain was safe in mice by monitoring body weight changes, performing histopathologic evaluations, and determining routine blood indices. We next evaluated the biological characteristics of the CL2 strain in terms of its growth, tolerance, and antibiotic susceptibility, with a focus on its ability to produce short-chain fatty acids. Finally, the intestinal flora structure of the experimental animals was analyzed to assess the intestinal environment compatibility of the CL2 strain. In this study, we isolated a cellulolytic B. cereus CL2, which has multiple cellulolytic functional genes and favorable biological characteristics, from the feces of Kele pigs. Moreover, CL2 could produce a variety of short-chain fatty acids and does not significantly affect the diversity of the intestinal flora. In summary, the cellulolytic bacterium B. cereus CL2 is a promising strain for use as a commercial probiotic or in feed supplement. IMPORTANCE:Short-chain fatty acids are crucial constituents of the intestinal tract, playing an important and beneficial role in preserving the functional integrity of the intestinal barrier and modulating both immune responses and the structure of the intestinal flora. In the intestine, short-chain fatty acids are mainly produced by bacterial fermentation of cellulose. Therefore, we believe that safe and efficient cellulolytic bacteria have the potential to be novel probiotics. In this study, we systematically evaluated the safety and biological characteristics of the cellulolytic bacterium B. cereus CL2 and provide evidence for its use as a probiotic.

Bacterial flagellin (FliC) can be used as a TLR5 ligand-like adjuvant. However, the sequences of hypervariable regions(HVR) of FliC from different bacteria vary, and their effects on adjuvants remain unclear. In this study, FliC Δ274–406 (deleting of D3 domain) and FliC Δ174–506 (deleting of D2-D3 domain) from Escherichia coli Nissle 1917 FliC (FliC EcN ) were constructed and expressed in host bacteria, BL21 . Purification was conducted using affinity chromatography on a Ni-NTA column, validation was done using SDS-PAGE and western blotting, the antigenicity and immunogenicity were detected using ELISA, and adjuvant effects were evaluated in Caco-2 cells and mice. The results showed that FliC EcN was mainly expressed in the bacterial supernatant, and the two truncated flagellins were expressed as inclusion bodies. Compared with FliC EcN , both FliC Δ274–406 and FliC Δ174–506 had considerable decreased antigenicity and immunogenicity. In Caco-2 cells, FliC Δ174–506 had a higher ability to promote the secretion of IL-8 than FliC EcN and FliC Δ274–406 . In mice, FliC Δ174–506 showed a comparable adjuvant level to FliC EcN , while FliC Δ274–406 was less effective. Our data shows that adjuvant effects of FliC EcN with deletion of different regions of its HVR are inconsistent, and deleting its entire D2–D3 domain is better.

Chlorogenic acid, the primary active component in Chinese medicines like honeysuckle, exhibits anti-inflammatory and antiviral effects. It has been demonstrated that chlorogenic acid effectively prevents and treats Duck enteritis virus (DEV) infection. This study aims to further elucidate the mechanism by which chlorogenic acid prevents DEV infection. Duck embryo fibroblast (DEF) cells were pre-treated with chlorogenic acid before being infected with DEV. Cell samples were collected at different time points for transcriptomic sequencing, while qPCR was used to detect the proliferation of DEV. Additionally, 30-day-old ducks were treated with chlorogenic acid, and their lymphoid organs were harvested for histopathological sections to observe pathological damage. The proliferation of DEV in the lymphoid organs was also detected using qPCR Based on the transcriptomic sequencing results, NF-κB1 gene was silenced by RNAi technology to analyze the effect of NF-κB1 gene on DEV proliferation. Compared to the viral infection group, DEF cells in the chlorogenic acid intervention group exhibited significantly reduced DEV load (P < 0.05). Transcriptomic sequencing results suggested that chlorogenic acid inhibited DEV proliferation in DEF cells by regulating NF-κB signaling pathway. The results of RNAi silencing suggested that in the three treatment groups, compared with the DEV experimental group, there was no significant difference in the effect of pre-transfection after transfection on DEV proliferation, while both the pre-transfection after transfection and the simultaneous transfection group showed significant inhibition on DEV proliferation Furthermore, compared to the virus infection group, ducks in the chlorogenic acid intervention group showed significantly decreased DEV load in their lymphoid organs (P < 0.05), along with alleviated pathological damage such as nuclear pyretosis and nuclear fragmentation. Chlorogenic acid effectively inhibits DEV proliferation in DEF and duck lymphatic organs, mitigates viral-induced pathological damage, and provides a theoretical basis for screening targeted drugs against DEV.

Bacterial flagellin is a potent immunomodulatory agent. Previously, we successfully obtained flagellin from Escherichia coli Nissle 1917 (FliCEcN) and constructed two mutants with varying degrees of deletion in its highly variable regions (HVRs). We found that there was a difference in immune stimulation levels between the two mutants, with the mutant lacking the D2–D3 domain pair of FliCEcN having a better adjuvant effect. Therefore, this study further analyzed the structural characteristics of the aforementioned FliCEcN and its two mutants and measured their levels of Caco-2 cell stimulation to explore the impact of different domains in the HVRs of FliCEcN on its structure and immune efficacy. This study utilized AlphaFold2, SERS (Surface-enhanced Raman spectroscopy), and CD (circular dichroism) techniques to analyze the structural characteristics of FliCEcN and its mutants, FliCΔ174-506 and FliCΔ274-406, and tested their immune effects by stimulating Caco-2 cells in vitro. The results indicate that the D2 and D3 domains of FliCEcN have more complex interactions compared to the D1-D2 domain pair., and these domains also play a role in molecular docking with TLR5 (Toll-like receptor 5). Furthermore, FliCΔ274-406 has more missing side chain and characteristic amino acid peaks than FliCΔ174-506. The FliCEcN group was found to stimulate higher levels of IL-10 (interleukin 10) secretion, while the FliCΔ174-506 and FliCΔ274-406 groups had higher levels of IL-6 (interleukin 6) and TNF-α (tumor necrosis factor-α) secretion. In summary, the deletion of different domains in the HVRs of FliCEcN affects its structural characteristics, its interaction with TLR5, and the secretion of immune factors by Caco-2 cells.

The purpose of the study was to analyze the structural characteristics of flagellin FliC (FliCEcN) of Escherichia coli Nissle 1917 and its stimulating effect on Caco-2 cells. FliCEcN protein was expressed by Escherichia coli BL21 (DE3), purified by NTA column and verified by SDS-PAGE and Western-blot. The structure model of FliCEcN protein was predicted by SOPMA and Alphold2, and the structure of FliCEcN protein was analyzed by surface enhanced Raman spectroscopy and circular dichroism spectroscopy. The secretion level of immune related factors was detected after stimulating Caco-2 cells with FliCEcN protein. The results showed that the size of FliCEcN protein was 64 kDa, which could be specifically recognized by anti-His monoclonal antibody. The amino and carboxyl terminals of FliCEcN protein were mainly composed of α-helix, and the intermediate domain is mainly composed of β-fold. The maximum absorption peaks of amide Ⅰ region of FliCEcN protein were all located at 1 656 cm-1, and the main secondary structures were α-helix and β-fold. FliCEcN's α-helix accounts for 44.4%, β-fold accounts for 23.4%, β-rotation angle accounts for 13.5%, and irregular curl accounts for 19.0%. The FliCEcN protein could effectively stimulate the secretion of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interleukin-10 (IL-10) in Caco-2 cells. With the increase of stimulation time, the secretion level of IL-6 decreased, while the secretion level of IL-10 and TNF-α increased. The results show that α-helix and β-folding are the main structures of FliCEcN, which can promote the correct folding of its conformation and maintain its three-dimensional structure stability. The FliCEcN protein stimulated Caco-2 cells to secrete IL-6, IL-10, and TNF-α levels is different.

[目的]探究鸭肠炎病毒(DEV)和A型产气荚膜梭菌(CpA)共感染的致病机制.[方法]研究选取37日龄健康非免疫雏鸭,随机分为对照组与共感染组.共感染组鸭于每天早晚各进行1次灌胃,每次灌CpA菌液8 mL(1×108 CFU/mL),连续5 d,首次灌胃72 h后于腿部肌肉接种DEV-GZ株病毒液(0.2 mL/只,TCID50=3.16× 10-9 TCID50/0.1 mL),对照组接种灭菌生理盐水0.2 mL,观察鸭临床病变及回肠剖检病变,采用细菌分离鉴定和PCR等方法检测DEV和CpA共感染模型是否成功建立.采集感染90 h对照组与共感染组回肠,采用液相色谱-质谱联用(LC-MS)技术对对照组及共感染组感染90 h鸭回肠进行代谢组学检测,筛选并分析潜在的差异代谢物及相关信号通路.[结果]经检测确定成功构建了鸭DEV和CpA共感染模型.对照组与共感染组鸭回肠差异代谢物质共有36种,在正离子模式下共有16种差异代谢物质,主要为2'-脱氧肌苷、腐胺、8(z),11(z),14(z)-二十碳三烯酸、胞苷和1-油酰基外消旋甘油,在负离子模式下共有20种差异代谢物质,主要为油酸、花生四烯酸、11(z),14(z)-二十二碳二烯酸、二十二碳三烯酸和亚油酸;差异代谢物主要富集的代谢通路为10条,主要为色氨酸代谢、嘧啶代谢、嘌呤代谢等.[结论]11(z),14(z)-二十二碳二烯酸、二十二碳三烯酸和花生四烯酸可成为DEV和CpA共感染鸭回肠的敏感生物标记物,提示DEV与CpA共感染加剧雏鸭回肠炎症,色氨酸代谢通路提示DEV与CpA共感染鸭免疫力变化存在联系.本研究为阐明DEV与CpA感染的致病机制奠定基础.

Introduction Duck enteritis virus (DEV) mainly causes infectious diseases characterized by intestinal haemorrhage, inflammation and parenchymal organ degeneration in ducks and other poultry. However, the mechanism by which it causes intestinal damage in ducks is not well understood. Metabolomics can provide an in-depth understanding of the full complexity of the disease. Methods In this study, 24 clinically healthy green-shell ducks (weight 1.5 kg ± 20 g) were randomly divided into 2 groups (experimental group, 18; control group, 6). The experimental group was intramuscularly injected with 0.2 mL of DEV virus in solution (TCID 50 3.16 × 10 8 PFU/mL), and the control group was injected with 0.2 mL of sterile normal saline. Duck duodenum and ileum tissue samples were collected at 66 h, 90 h and 114 h post-injection (12 h of fasting before killing), and metabolomics analysis of duck duodenum and ileum tissues at the three time points (66, 90, 114 h) was performed by liquid chromatography–mass spectrometry (LC–MS) to screen for and analyse the potential differentiated metabolites and related signalling pathways. Results Screening was performed in the positive/negative mode (Pos: Positive ion mode; the ionization of substances at the ion source with positive ions such as H + , NH 4 + , Na + and K + ; Neg: Negative ion mode; the ionization of substances at the ion source with negative ions such as Cl − , OAc − ), and compound abundance was compared to that in the control group. The total number of differentially abundant compounds in the duodenum at 66 h, 90 h and 114 h of DEV infection gradually increased, and metabolites such as cytidine, 2′-deoxyriboside and 4-guanidinobutyric acid were differentially abundant metabolites common to all three time periods. The metabolic pathways related to inflammatory response and immune response were tryptophan acid metabolism, cysteine-methionine metabolism, histidine metabolism and other amino acid metabolism and fat metabolism. Among them, the metabolic pathways with more differentially abundant metabolites were amino acid biosynthesis, cysteine and methionine metabolism, tryptophan metabolism, unsaturated fatty acid biosynthesis and purine metabolism, and the metabolic pathways with more enrichment factors were the IgA-related intestinal immune network pathway and lysosome pathway. Compared with the control group, there were 16 differentially abundant metabolites in the ileum tissue of DEV-infected ducks at 66 h of infection, 52 at 90 h of infection, and 40 at 14 h of infection with TD114. The metabolic pathways with more enriched differentially abundant metabolites were pyrimidine metabolism, tyrosine metabolism, phenylalanine metabolism and tryptophan biosynthesis. The metabolic pathways with the most enrichment factors were the mTOR signalling pathway, ferroptosis pathway, tryptophan metabolism pathway and caffeine metabolism pathway. Conclusion Comparative analysis showed that the number of differentially abundant metabolites in the duodenum and ileum differed to some extent after DEV infection, with significantly more differentially abundant metabolites in duodenal tissues and fewer in ileal tissues; after DEV infection, the highest number of differentially abundant metabolites was obtained at 114 h of DEV infection, followed by the second highest at 90 h of infection and the lowest at 66 h of infection. The common differentially abundant metabolites in duodenal and ileal tissues were prostaglandins, arachidonic acid, and arachidonic ethanolamine. The main metabolic pathways in the duodenum were the IgA-associated intestinal immune network pathway and the lysosomal pathway, and the metabolic pathways with more enriched factors in the ileum were the mTOR signalling pathway, the ferroptosis pathway, and the tryptophan metabolism pathway.

Over the past 20 years, a variety of potential adjuvants have been studied to enhance the effect of oral vaccines in the intestinal mucosal immune system; however, no licensed adjuvant for clinical application in oral vaccines is available. In this review, we systematically updated the research progress of oral vaccine adjuvants over the past 2 decades, including biogenic adjuvants, non-biogenic adjuvants, and their multi-type composite adjuvant materials, and introduced their immune mechanisms of adjuvanticity, aiming at providing theoretical basis for developing feasible and effective adjuvants for oral vaccines. Based on these insights, we briefly discussed the challenges in the development of oral vaccine adjuvants and prospects for their future development.

Abstract This study aimed to investigate the structural characteristics and their effects on stimulating Caco-2 cells of Escherichia coli Nissle 1917 flagellin (FliCEcN) and its truncated proteins, FliC△174−506 (D2-D3 domain deleted) and FliC△274−406 (D3 domain deleted). The experiment predicted the tertiary structure of FliCEcN by Alphofold2, analyzed the structural characteristics of FliCEcN, FliC△174−506 and FliC△274−406 by surface-enhanced Raman spectroscopy (SERS) and circular dichroism (CD), and detected the secretion levels of IL-6 (interleukin-6), IL-10 (interleukin-10) and TNF-α (tumor necrosis factor-α) after FliCEcN, FliC△174−506 and FliC△274−406 stimulated Caco-2 cells for 6 and 12 h, respectively. The results showed that the NH3-ends and COOH-ends of FliCEcN were highly conserved, mainly composed of α-helix; the middle domains were highly variable, mainly composed of β-sheet and random coil. The Raman peaks of FliC△174−506 and FliC△274−406 generally maintained the main chain peaks of FliCEcN, while the side chain and amino acid peaks were absent to varying degrees. The composition of the secondary structure of FliC△174−506 and FliC△274−406 was altered. FliCEcN, FliC△174−506 and FliC△274−406 stimulated Caco-2 cells to secrete cytokines IL-10, IL-6 and TNF-α differently. The complete FliCEcN structure could stimulate more secretion of IL-10; the FliC△174−506 group had higher secretion of IL-6; and the FliC△274−406 group had higher secretion of TNF-α. In conclusion, deletion of different domains of the hypervariable region of FliCEcN affects its SERS and CD spectrum and stimulates Caco-2 cells to secrete cytokines.

试验旨在分析鞭毛蛋白刺激机体基因表达谱的特征,揭示鞭毛蛋白佐剂的作用机制.从GEO数据库筛选目标微阵列GSE46421和GSE72016及其差异表达基因(DEGs),经DAVID分析DEGs参与的GO功能注释和KEGG信号通路、String构建DEGs的蛋白质-蛋白质相互作用(PPI)网络、Cytoscape可视化PPI网络并筛选高连通度的PPI子模块和hub基因.结果显示,共筛选出182个DEGs,包含上调基因161个、下调基因121个.DEGs参与GO生物过程主要有信号转导、免疫应答、炎症反应、细胞凋亡等,参与分子功能包含激酶激活、受体结合、细胞因子激活、膜信号转导.DEGs参与KEGG通路涵盖细胞因子-细胞因子受体相互作用、TNF信号通路、NF-κB信号通路、Toll样受体信号通路、NOD样受体信号通路等免疫相关途径.分析DEGs的PPI网络发现,2个重要的PPI子模块和10个关键基因(IL-10、IL-6、CCL2、CXCL2、NFKBIA、MyD88等).研究表明,鞭毛蛋白通过识别TLR5和NOD样受体,触发MyD88依赖性和MyD88非依赖性途径发出信号,激活转录因子NF-κB,这些信号通过级联反应激活机体免疫系统、诱导机体产生多种细胞因子和趋化因子,发挥佐剂效应.

The randomized base pairing in the interval of IBS2 and IBS1 of Tel3c/4c intron (−8 and −7 sites) in Thermotargetron (TMT) results in a low success rate and gene-targeting efficiency in bacteria. In the present work, we constructed a randomized gene-targeting plasmids pool (RGPP) to study whether there is a base preference in target sequences.

为探究免疫增强剂在鲟鱼养殖中的应用效果,选取月龄、体重相近的鲟鱼 200 尾,按照试验设计分为 4 组,其中 3个试验组分别添加胸腺肽、绿原酸、壳寡糖 200 mg/kg于基础饲料中,对照组只饲喂基础饲料,分别于正试验开始后第 14、28、42d采集样品,测定鲟鱼生长性能及血清生化指标.结果:(1)与对照组相比,试验组增重率及特定生长率均不同程度提高.28d时绿原酸组和壳寡糖组增重率及特定生长率均显著提高(P<0.05);42d时胸腺肽组和绿原酸组增重率及特定生长率均显著提高(P<0.05),壳寡糖组增重率及特定生长率均极显著提高(P<0.01);28、42d时壳寡糖组肝脏指数均显著降低(P<0.05).(2)与对照组相比,14d时试验组血清总蛋白、白蛋白、球蛋白含量极显著升高(P<0.01).42d时胸腺肽组球蛋白含量显著降低(P<0.05),绿原酸组和壳寡糖组血清尿酸、尿素氮、谷丙转氨酶、谷草转氨酶含量显著降低(P<0.05);14d时胸腺肽组血清尿素氮含量显著降低(P<0.05),42d时谷丙转氨酶含量显著升高(P<0.05).结论:在基础饲料中分别添加胸腺肽、绿原酸、壳寡糖 200 mg/kg均能促进鲟鱼生长,增加蛋白质合成速率,提高机体代谢水平,增强机体免疫能力;但长期使用胸腺肽可对肝脏造成一定损伤,表现为 42d时球蛋白含量显著降低,谷丙转氨酶显著升高.

Abstract Introduction Duck enteritis virus (DEV) mainly causes infectious diseases characterized by intestinal hemorrhage, inflammation and parenchymal organ degeneration in ducks and other poultry. However, its mechanism of intestinal damage in ducks is not well understood. Metabolomics can provide an in-depth understanding of the full complexity of the disease. Methods In this study, 24 clinically healthy green-shell ducks (weight 1.5kg ± 20g) were randomly divided them into 2 groups (experimental group of 18 rats and control group of 6 rats). The experimental group was intramuscularly injected with 0.2 mL of DEV virus liquid (TCID50 is 3.16×10 -9 /0.1 mL), and the control group was injected with 0.2 sterilized normal saline. mL; at 66 h, 90 h and 114 h after injection (fasting for 12 h before killing), tissue samples from the duodenum and ileum were collected and analyzed by LC-MS. Results Compared with the control group, in the positive/negative mode, the metabolic pathways involved in the differential metabolites in the duodenum of DEV-infected ducks at 66h, 90h and 114h were basically the same; the metabolic pathways related to inflammatory response and immune response were tryptophan Acid metabolism, cysteine-methionine metabolism, histidine metabolism and other amino acid metabolism and fat metabolism. Among them, the metabolic pathways with more differential metabolites are amino acid biosynthesis, cysteine and methionine metabolism, tryptophan metabolism, Unsaturated fatty acid biosynthesis and purine metabolism, the metabolic pathways with more enrichment factors were IgA-related intestinal immune network pathway and lysosome pathway. Compared with the control group, there were 16 differential metabolites in the ileum tissue of DEV-infected ducks at 66 hours of infection, 52 at 90 hours of infection, and 40 at 14 hours of infection with TD114, among which the metabolic pathways with more enriched differential metabolites were Pyrimidine metabolism, tyrosine metabolism, phenylalanine metabolism and tryptophan biosynthesis, the metabolic pathways with more enrichment factors are mTOR signaling pathway, ferroptosis pathway, tryptophan metabolism pathway and caffeine metabolism pathway Conclusion The differential metabolites of DEV-infected ducks are enriched in metabolic pathways such as tryptophan metabolism, amino acid biosynthesis, cysteine-methionine metabolism, unsaturated fatty acid biosynthesis and purine metabolism, among which tryptophan metabolism pathway The enrichment is the most obvious and can be used as a follow-up study;