Yuejie Zhu

Brucellosis, caused by the intracellular pathogen Brucella , remains a significant health challenge, alongside substantial economic impacts on livestock industries. Despite antibiotic treatments, the absence of licensed human vaccines necessitates innovative preventive strategies. In this study, we employed reverse vaccinology to design a novel multi-epitope vaccine (MEV) targeting Brucella melitensis . Three immunogenic proteins—outer membrane protein OMP31, LPS assembly protein LptE, and the type IV secretion system protein VirB2—were selected as vaccine candidates. Comprehensive bioinformatics analysis identified six cytotoxic T lymphocyte (CTL) epitopes, nine helper T lymphocyte (HTL) epitopes, seven linear B-cell epitopes, and five conformational B-cell epitopes. The incorporation of molecular adjuvants (cholera toxin B subunit and PADRE) served to further enhance the immunogenicity of the vaccine. Given that Brucella is an intracellular parasite, TAT cell-penetrating peptides were added to further enhance the intracellular delivery of MEV. The constructed MEV has been shown to have excellent antigenicity (VaxiJen score >0.8), stability (instability index in silico cloning simulation of the codon-optimized multi-epitope vaccine (MEV) sequence into the pMV261 shuttle vector, generating a recombinant BCG (rBCG) construct. Immunoinformatics simulations (C-ImmSim) demonstrated potent immune activation, with significant increases in cytotoxic T cells (1050 cells/mm³), memory helper T cells (1150 cells/mm³), and IFN-γ production (2 × 10^6 ng/ml), alongside sustained IgG/IgM titers over 350 days(1 × 10^5 cells/mm ³ ) . Furthermore, the recombinant BCG multi-epitope Brucella vaccine, developed through bioinformatics approaches, demonstrates promising characteristics and immunogenicity. Nevertheless, its immunological efficacy requires to further experimental validation.

Background: Brucellosis is a zoonotic disease that is widely prevalent in the Xinjiang region of China. Once it progresses to a chronic stage, it can lead to significant complications. Immune checkpoints markers on Myeloid-derived suppressor cells (MDSCs) may lead to the chronic stage of the disease. This study analyzed the changes in MDSCs, immune checkpoints markers and cytokines in the patients with acute and chronic Brucella infections and after antibiotic treatment, to explore their roles and provide new ideas for future clinical treatment. Methods: A total of 37 patients with acute brucellosis infection (ABI) and 46 patients with chronic brucellosis infection (CBI) and 43 healthy controls (HC) subjects were enrolled. Flow cytometry was used to detect the expression of MDSCs, Siglec-9 ⁺ MDSCs, PD-1 ⁺ MDSCs and Tim-3 ⁺ MDSCs before and after antibiotic treatment. In addition, ELISA was used to measure the levels of cytokines and the changes in IL-6 and Arg-1 of them were assessed again after antibiotic treatment. Results: Our study found that the levels of MDSCs in the patients significantly increased, with CBI patients exhibiting higher levels than ABI patients. The cytokines showed varying degrees of elevation. Furthermore, after antibiotic treatment, the levels of MDSCs, Siglec-9 ⁺ MDSCs, PD-1 ⁺ MDSCs and Tim-3 ⁺ MDSCs in effective treatment patients significantly decreased. In contrast, the levels of MDSCs in ineffective treatment patients increased, while there were no significant differences in PD-1 ⁺ MDSCs and Tim-3 ⁺ MDSCs levels compared to before treatment. Notably, the levels of Siglec-9 ⁺ MDSCs in ineffective treatment showed a significant increase. In the ineffective treatment patients, the serum levels of Arg-1 and IL-6 both increased compared to before treatment. Correlation analysis revealed a positive correlation in ineffective treatment patients between serum Arg-1 levels and MDSCs, as well as Siglec-9 ⁺ MDSCs levels, while no correlation was observed between IL-6 levels and immune cell parameters. Conclusion: MDSCs are increased in both ABI and CBI. Siglec-9 acts as an immune checkpoint on MDSCs in patients with ineffective treatment responses. Therefore, Siglec-9 represents a potential prognostic marker for Brucella infection. Ongoing research on prognostic markers of brucellosis is promising, and further clinical studies are warranted to validate these findings.

Brucella spp., the causative agent of zoonotic brucellosis, poses a significant threat to both animal husbandry and human health. Given the limitations of current antibiotic treatments for human brucellosis, there is an urgent need to develop effective human vaccines. Using reverse vaccinology and bioinformatics approaches, we designed a multi-epitope vaccine (MEV) specifically targeting the CcmA, ccmC, and BepC membrane proteins, with the aim of providing robust protection against human infection.We screened 11 CTL, 9 HTL, 2 conformational B cell epitopes, and 9 linear B cell epitopes, linked them with GGGS,GPGPG and KK. and incorporated HMGN1 (high mobility group nucleosome binding protein 1) as an adjuvant and PADRE (a universal HTL epitope to enhance cross-population immunogenicity) to boost immunogenicity. Analyses showed the 638-amino-acid MEV had high antigenicity (1.2542, exceeded the threshold of 0.4), was non-toxic(ToxinPred2) and non-allergenic(AllergenFP), had low human homology(BLASTP e-value < 0.005), Instability index 26.80 (< 40),and good solubility(0.896, > 0.5).Molecular docking and dynamics confirmed its stability. Codon optimization for E. coli enhanced expression potential. Immunoinformatics simulations showed the MEV effectively increased antibody level,T cell counts, and proinflammatory cytokines.In conclusion, the MEV shows promise for brucellosis vaccine development. To fully assess its efficacy and safety, a series of in vivo experiments will be conducted using animal models, which will serve as a critical step towards validating its potential as a viable vaccine candidate.

Brucellosis is a zoonotic disease caused by bacteria of the Brucella genus. This study investigates the development of a multi-epitope mRNA vaccine aimed at combating Brucella infections. The approach involves selecting the architecture of the pathogenic type IV secretion system (T4SS) of Brucella using bioinformatics tools and reverse vaccinology methodologies. The candidate proteins chosen for this vaccine include VirB2, VirB3, and VirB6, along with the effector protein BtpA. Key findings include robust antigenicity scores for the candidate proteins (VirB2:0.5685; VirB3:0.5329;VirB6:0.5054;BtpA:0.5575).A variety of tools were essential for identifying potential epitopes suitable for incorporation into the mRNA vaccine, as well as for utilizing appropriate linkers for docking. Molecular dynamics simulations confirmed stable interactions between the vaccine and TLR4, with a docking score of − 350.15. Furthermore, computer cloning methods were employed alongside simulated gel electrophoresis to ensure a comprehensive evaluation of the vaccine’s properties. The results of this investigation indicate that the newly formulated mRNA vaccine effectively stimulates an immune response, presenting innovative strategies for prevention and management. Although comprehensive evaluations of vaccine design have been conducted using bioinformatics tools and molecular simulations, certain limitations still exist, primarily manifested in the reliance on computational predictions without validation from wet lab experiments. Future research must further verify the accuracy of computational results through laboratory experiments.

In the published article, there was an error in the placement of the legends for Figure 1 Hematopoietic stem cells (HSCs) represent the origin of all blood cells, giving rise to common myeloid progenitors (CMPs) and common lymphoid progenitors (CLPs). CLPs further differentiate into all lymphocyte lineages. Early innate lymphoid cell progenitors (EILPs) develop into all ILC subsets, while common helper-like ILC progenitors (CHILPs) and ILC progenitors (ILCPs) retain multi-lineage potential. The figure shows key transcription factors (including TCF-1, ID2, PLZF, GATA3, Bcl11b), phenotypic markers (such as IL-7R, Flt3, α4β7, PD-1, KLRG1, ST2, IL-25R), and effector molecules (IL-5, IL-13, AREG) characterizing each developmental stage and mature ILC subset. ILC2 can be divided into two subtypes: nILC2 and iILC2. nILC2 resides in barrier tissues and expresses low levels of IL-25R, while iILC2 appears at inflammatory sites and is characterized by low levels of ST2 expression.

The intestinal mucosal immune system maintains homeostasis through complex interactions between epithelial cells and innate lymphoid cells in the lamina propria. Tuft cells, previously overlooked intestinal epithelial cell types, detect parasites and metabolites via Sucnr1 and TAS2R receptors. They secrete IL-25, which activates type 2 innate lymphoid cell (ILC2) via the IL-25R receptor. ILC2 releases IL-13, resulting in further promotion of tuft and goblet cells from stem cells. This positive feedback loop amplifies the local type 2 immune response, combating parasitic infections. Tuft cells also recognize viruses and bacteria, but the role played by the tuft cell-ILC2 circuit in this process is not yet clear. Furthermore, tuft cell-ILC2 circuit is influenced by dietary fiber, intestinal microbiota, and other factors, contributing to new functions in maintaining intestinal homeostasis. In inflammatory bowel disease, this immunological circuit may be protective. This review summarizes the current understanding of the tuft cell-ILC2 circuit, its regulatory mechanisms, and potential implications in intestinal disease. Graphical abstract (by Figdraw 2.0)

Purpose Polycystic ovary syndrome (PCOS) is a leading cause of anovulatory infertility and closely correlated with apoptosis in ovarian granulosa cells (GCs). Programmed cell death protein-1/programmed cell death ligand-1 (PD-1/PD-L1) pathway plays an important role throughout gestation and the pathogenesis of adverse pregnancy outcomes, but its mechanism in PCOS remains unclear. Methods The RNA sequencing data for PCOS patients were downloaded from the Gene Expression Omnibus (GEO) databases. Bioinformatics analysis was conducted to identify differentially expressed PD-1/PD-L1 pathway genes (DEPPGs) and related signaling pathways. PCOS mouse model was established by injecting dehydroepiandrosterone (DHEA), apoptosis of ovarian GCs in PCOS mouse were detected by TUNEL staining. The main genes and proteins in the PI3K/AKT signaling pathway and apoptosis were detected by qRT-PCR and Western blot analyses after PD-L1 intervention in GCs. Finally, the hub gene of differentially expressed PI3K/AKT pathway genes (DEPAGs) in GCs was evaluated in PCOS patients. Results The DEPPGs in GCs and oocyte were identified, showing enrichment in Th1 and Th2 cell differentiation, apoptosis, and PI3K/AKT signaling pathway. More apoptosis was observed in ovarian GCs of PCOS mice. In vitro experiments showed that PI3K/AKT pathway was activated and the apoptosis of GCs was suppressed after PD-L1 intervention. The hub gene COL1A1 was upregulated in the GCs of PCOS patients. Conclusions PD-L1 may reduce the apoptosis of GCs through PI3K/AKT signaling pathway activation, providing a novel strategy for inhibiting the apoptosis of GCs in PCOS.

Brucellosis has become a global zoonotic disease, seriously endangering the health of people all over the world. Vaccination is an effective strategy for protection against Brucella infection in livestock in developed countries. However, current vaccines are pathogenic to humans and pregnant animals, which limits their use. Therefore, it is very important to improve the safety and immune protection of Brucella vaccine. In this study, different bioinformatics approaches were carried out to predict the physicochemical properties, T/B epitope, and tertiary structure of Omp2b and Omp31. Then, these two proteins were sequentially linked, and the Cytotoxic T lymphocyte associated antigen-4 (CTLA-4) variable region was fused to the N-terminal of the epitope sequence. In addition, molecular docking was performed to show that the structure of the fusion protein vaccine had strong affinity with B7 (B7-1, B7-2). This study showed that the designed vaccine containing CTLA-4 had high potency against Brucella, which could provide a reference for the future development of efficient brucellosis vaccines.

This study is to investigate the relationship of programmed cell death 1 (PD‐1; also known as PDCD1) and programmed death‐1‐ligand 1 (PD‐L1; also known as CD274) single nucleotide polymorphisms (SNPs) with polycystic ovary syndrome (PCOS). This study enrolled 330 PCOS patients and 350 matched controls. ELISA was used to detect the PD‐1 and PD‐L1 levels in serum. SnaPshot genotyping was performed to analyze the PD‐1 and PD‐L1 genotyping. Linkage disequilibrium and haplotype of TagSNP loci of PD‐1 and PD‐L1 genes were also detected. The relationship of genotypes and alleles with PCOS was analyzed. The levels of PD‐1 and PD‐L1 in the serum of PCOS patients were significantly lower than those in the control group (P < 0.01). The haplotype TT of PD‐1 gene at rs10204525 and rs7421861 loci was significantly lower in the PCOS group than in the control group (P < 0.001, OR = 0.67, and 95%CI = 0.54‐0.84). PD‐L1 gene SNP loci rs2282055, rs2890658, rs10125854, and rs702275 had linkage disequilibrium. The haplotypes TAAA, GAAC, GAGC, GCAA, and TCGA of PD‐L1 gene SNP loci were significantly higher in PCOS patients than in the control group, whereas haplotypes GAAA, TAAC, TCAA, GCGA, GCAC, and TCGC of PD‐L1 gene SNP loci were significantly lower in PCOS patients than in the control group. PD‐1 and PD‐L1 SNPs may be related to the pathogenesis of PCOS. PD‐1 gene SNP loci rs10204525 and rs7421861 and PD‐L1 gene SNP loci rs2282055, rs2890658, rs10125854, and rs702275 may be new candidate polymorphic loci for PCOS.

With the rapid development of synthetic technology and biological technology, many nucleic acid‐based drugs have entered the clinical trials. However, their inherent disabilities in actively and efficiently penetrating cell membranes still severely restrict their further application. The main drawback of cationic lipids, which have been widely used as nonviral vectors of nucleic acids, is their high cytotoxicity. A series of nucleoside‐based or nucleotide‐based nucleolipids have been reported in recent years, due to their oligonucleotide delivery capacity and low toxicity in comparison with cationic lipids. Lipophilic prodrugs of nucleoside analogs have extremely similar structures with nucleolipid vectors and are thus helpful for improving the transmembrane ability. This review introduces the progress of nucleolipids and provides new strategies for improving the delivery efficiency of nucleic acid‐based drugs, as well as lipophilic prodrugs of nucleosides or nucleotides for antiviral or anticancer therapies.