This study investigated the specific immune response of BALB/c mice that was induced by a circular RNA (circRNA) vaccine expressing the herpes simplex virus type II (HSV-2) glycoprotein D (gD). The aim was to evaluate the immunological potential of this vaccine and lay a foundation for developing an mRNA vaccine against HSV-2. PCR and homologous recombination were employed to integrate the gD gene obtained from the pT7AMP-gD ectodomain plasmid into pUC57 to generate the recombinant plasmid pUC57-circ-gD, which was then sequenced and characterized. In vitro transcription and cyclization were performed on the template DNA to generate pUC57-circ-gD mRNA. To validate the formation of circular RNA, we cleaved the pUC57-circ-gD mRNA with RNase R and employed RT-PCR to validate the cyclization. The pUC57-circ-gD mRNA was then transfected into 293T cells. After 72 h, the cell supernatant was collected, and Western blotting was employed to measure the protein level of gD. Subsequently, the mRNA was encapsulated in lipid nanoparticles (LNPs) by microfluidic encapsulation. BALB/c mice were administrated with the encapsulated mRNA, and blood was collected from the fundus venous plexus after 21 and 35 days, and from the enucleated eyeballs after 49 days. Enzyme-linked immunosorbent assay was employed to measure the titers of antibodies, including virus-neutralizing antibodies. After 49 days, spleens were harvested and assessed for secretion of interferon-gamma (IFN-γ) by solid-phase enzyme-linked immunospot. The results showed successful construction and sequencing of the recombinant plasmid. RNase R digestion confirmed the presence of circular RNAs. Western blotting of the 293T cells transfected with the mRNA showed clear specific bands. The quality of the vaccine was tested by size exclusion chromatography-high performance liquid chromatography, which showed that the purity of the vaccine was about 90%. The mRNA-LNP showcased the particle size of 82.76 nm and an encapsulation rate of approximately 98%. Following three-dose vaccination, all immunized mice exhibited steady weight gain with 100% survival rate throughout the 28-day observation period, indicating no significant acute toxicity associated with the vaccine formulation. The immunized mice showed dose-dependent increases in serum IgG antibody titer and IFN-γ secretion by splenocytes and they were resistant to virus attacks. These findings indicate good immunogenicity and persistence of the pUC57-circ-gD mRNA vaccine, providing a reference for further studies on circRNA vaccines.
Animals ; Mice, Inbred BALB C ; RNA, Circular ; Mice ; Humans ; Herpesvirus 2, Human/genetics* ; Viral Envelope Proteins/genetics* ; Antibodies, Viral/blood* ; HEK293 Cells ; Female ; Nanoparticles ; Plasmids

This study aims to investigate the potential of oncolytic nanoparticles encapsulating Coxsackievirus A21 (CVA21) full-genome mRNA (CVA21@ONP) to resurrect CVA21 and induce apoptosis in host cells, as well as the antitumor immune effects of CVA21@ONP in immunocompetent tumor-bearing BALB/c mice. We used lipid nanoparticles (LNPs) to encapsulate CVA21 full-genome mRNA, thus preparing CVA21@ONP. The killing efficacy of CVA21@ONP was determined by the plaque assay and cell counting kit-8 (CCK-8), and the apoptosis in HT29 and CT26-iRFP cells was evaluated by flow cytometry. Mice were administrated with CVA21@ONP at high and low doses intratumorally, and the growth of tumors expressing infra-red fluorescent protein (iRFP) was monitored. Additionally, the types and changes of immune cells in the spleen were analyzed by flow cytometry. The results demonstrated that CVA21@ONP successfully resurrected CVA21 in both HT29 and U87MG cells. The plaque assay revealed robust killing effects of CVA21@ONP against both human and murine cell lines, and flow cytometry results showed increased early and late apoptotic cells. Notably, intratumoral detection revealed significantly down-regulated expression of iRFP in both high- and low-dose CVA21@ONP groups. Flow cytometry results further indicated that CVA21@ONP treatment effectively reduced the levels of immunosuppressive cells, including myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs), in the spleen, while enhancing T cell-dependent antitumor immune responses. These findings suggest that CVA21@ONP can replicate and survive extensively both in vitro and in vivo, activating the immune system of mice administrated with CVA21@ONP to target cells at the tumor site, thereby remodeling the tumor immune microenvironment and accelerating the suppression or even complete regression of tumors. The oncolytic performance of CVA21@ONP has been verified through intratumoral injection administration in this study, aimed at further exploring its therapeutic potential and promoting the development of the field of tumor treatment.
Animals ; Nanoparticles/chemistry* ; Mice ; Mice, Inbred BALB C ; Humans ; Apoptosis ; Oncolytic Viruses/genetics* ; Oncolytic Virotherapy/methods* ; Cell Line, Tumor ; RNA, Messenger/genetics* ; HT29 Cells

To investigate the mechanism of the major capsid protein VP5 (encoded by the UL19 gene) of oncolytic herpes simplex virus type Ⅱ (oHSV2) in regulating the antitumor function of immune cells, we constructed a mouse breast cancer cell line 4T1-iRFP-VP5-GFP stably expressing VP5 protein, near-infrared fluorescent protein (iRFP), and green fluorescent protein (GFP) by using the PiggyBac transposon system. Flow cytometry and Western blotting were employed to screen the monoclonal cell lines expressing both GFP and VP5 and examine the expression stability of UL19 in the constructed cell line. The results of SYBR Green I real-time PCR and Western blotting showed that the copies of UL19 and the expression level of VP5 protein in the 15th passage of 4T1-iRFP-VP5-GFP cells were significantly higher than those in the 4T1 cells transiently transfected with UL19, demonstrating the stable insertion of UL19 into the 4T1 cell genome. The real-time cell analysis (RTCA) was employed to monitor the proliferation of 4T1-iRFP-VP5-GFP cells, which showed similar proliferation activity to their parental 4T1 cells. Further studies confirmed that NK92 cells exhibited stronger cytotoxicity against 4T1-iRFP-VP5-GFP cells than against 4T1 cells. This study layed a foundation for elucidating the role of VP5 protein in regulating immune cells, including T cells and NK cells, via HLA-E in 4T1 cells to exert the anti-tumor function.
Animals ; Mice ; DNA Transposable Elements/genetics* ; Cell Line, Tumor ; Capsid Proteins/biosynthesis* ; Transfection ; Green Fluorescent Proteins/metabolism* ; Oncolytic Viruses/genetics* ; Female ; Simplexvirus/genetics*

OBJECTIVES: To explore the risk factors for femoral neck fracture in elderly population. METHODS: A total of 124 elderly patients (≥60 years old) in hospital for trauma were enrolled, including 71 patients (57%) with femoral neck fracture and 53 non-femoral neck fracture patients (43%). All patients' age, gender, body mass index (BMI), bone mineral density (BMD), thigh length and average circumference were collected. Single factor analysis and multivariate logistic regression analysis were performed to explore whether the above factors were risk factors for femoral neck fracture. RESULTS: Single factor analysis showed that the age, gender, BMI, BMD, thigh length, and average thigh circumference between the 2 groups were statistically different (all CONCLUSIONS Older age, female, lower BMI index (low body weight), lower BMD (osteoporosis), longer thigh length, and lower average circumference are risk factors for femoral neck fracture in the elderly population.
Absorptiometry, Photon ; Aged ; Body Mass Index ; Bone Density ; Female ; Femoral Neck Fractures/etiology* ; Humans ; Middle Aged ; Osteoporosis ; Risk Factors

Background: Antimicrobial peptides (AMPs) have been identified as promising compounds for consideration as novel antimicrobial agents. Objectives: This study analyzed the efficacy of cecropin B against Haemophilus parasuis isolates through scanning electron microscopy (SEM) and atomic force microscopy (AFM) experiments. Results: Cecropin B exhibited broad inhibition activity against 15 standard Haemophilus parasuis (HPS) strains and 5 of the clinical isolates had minimum inhibition concentrations (MICs) ranging from 2 to 16 μg/mL. Microelectrophoresis and hexadecane adsorption assays indicated that the more hydrophobic and the higher the isoelectric point (IEP) of the strain, the more sensitive it was to cecropin B. Through SEM, multiple blisters of various shapes and dents on the cell surface were observed. Protrusions and leakage were detected by AFM. Conclusions Based on the results, cecropin B could inhibit HPS via a pore-forming mechanism by interacting with the cytoplasmic membrane of bacteria. Moreover, as cecropin B concentration increased, the bacteria membrane was more seriously damaged. Thus, cecropin B could be developed as an effective anti-HPS agent for use in clinical applications.

Background: Antimicrobial peptides (AMPs) have been identified as promising compounds for consideration as novel antimicrobial agents. Objectives: This study analyzed the efficacy of cecropin B against Haemophilus parasuis isolates through scanning electron microscopy (SEM) and atomic force microscopy (AFM) experiments. Results: Cecropin B exhibited broad inhibition activity against 15 standard Haemophilus parasuis (HPS) strains and 5 of the clinical isolates had minimum inhibition concentrations (MICs) ranging from 2 to 16 μg/mL. Microelectrophoresis and hexadecane adsorption assays indicated that the more hydrophobic and the higher the isoelectric point (IEP) of the strain, the more sensitive it was to cecropin B. Through SEM, multiple blisters of various shapes and dents on the cell surface were observed. Protrusions and leakage were detected by AFM. Conclusions Based on the results, cecropin B could inhibit HPS via a pore-forming mechanism by interacting with the cytoplasmic membrane of bacteria. Moreover, as cecropin B concentration increased, the bacteria membrane was more seriously damaged. Thus, cecropin B could be developed as an effective anti-HPS agent for use in clinical applications.

Autophagy is a physiological process of normal cells that is activated in response to accumulation of abnormal proteins, damaged organelles, and cell starvation and involves their transport to lysosomes for degradation and recycling, enabling the mainte-nance of cellular homeostasis. Oncolytic viruses, which are obtained from naturally occurring or genetically modified viruses, specifical-ly target and kill tumor cells. Despite receiving much attention, the mechanisms underlying this process remain unclear, although re-cent studies have implicated autophagy in the phenomenon. Here we outline how oncolytic viruses cause cell death via autophagy and how they can be exploited for the treatment of cancer.

The interaction between oncolytic virus (OV) and the tumor microenvironment or body immune system is critical to the outcome of antitumor therapy. The antitumor mechanism of OV is complex, which involves direct cytotoxic effects, immunogenicity change in tumor microenvironment, the role of tumor vasculature, and activating of the antitumor immunity response, to reach the goal of killing the tumor cells infected or uninfected, and confirming the continous favorable effects.

Objective: To evaluate the oncolytic effect of herpes simplex virus type 1 which carried recombined human granulocyte-macrophage colony-stimulating factor (HSV1-hGM-CSF) on the mouse breast cancer cell line 4T1 and compare the anticancer effects of HSV1-hGM-CSF, doxorubicin alone or combination on the breast cancer in mice. Methods: We investigated the cytotoxic effect on 4T1 cells in vitro, the cell growth, cell apoptosis and cell cycle of 4T1 cells treated with oncolytic HSV1-hGM-CSF at different MOIs (0, 0.5, 1 and 2) and doxorubicin at different concentrations (0, 2, 4 and 8 μg/ml). The effects of oncolytic HSV1-hGM-CSF and doxorubicin on the tumor growth, survival time and their side effects on the mouse breast cancer model were observed. Results: Both oncolytic HSV1-hGM-CSF and doxorubicin significantly inhibited the proliferation of 4T1 cells in vitro. Doxorubicin induced the G₂/M phase arrest of 4T1 cells, while the cytotoxicity of oncolytic HSV1-hGM-CSF was no cell cycle-dependent.At day 16 after treatment with doxorubicin and HSV1-hGM-CSF, the tumor volume of 4T1 tumor bearing mice were (144.40±27.68)mm^3, (216.80±57.18)mm^3, (246.10±21.90)mm^3, (327.50±44.24)mm^3, (213.30±32.31)mm³ and (495.80±75.87)mm³ in the groups of doxorubicin combined with high dose HSV1-hGM-CSF, doxorubicin combined with low dose HSV1-hGM-CSF, doxorubicin alone, high dose HSV1-hGM-CSF alone, low dose HSV1-hGM-CSF alone and control, respectively.Compared with the control group, both doxorubicin and HSV1-hGM-CSF treatment exhibited significant reduction of primary tumor volume in vivo (P<0.001). The median survival times were 48, 50, 40, 42, 43 and 37 days in the six groups mentioned above, respectively. The median survival period of doxorubicin alone, high dose HSV1-hGM-CSF alone and low dose HSV1-hGM-CSF alone were significantly longer than that of control (P<0.05). Conclusion Synergistic effect of sequential treatment with doxorubicin and oncolytic HSV1-hGM-CSF is observed in 4T1 mouse breast cancer.