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

Objectives:To evaluate the imaging effects of the novel sympathetic nerve imaging agent 18F-FPMBBG in healthy volunteers and heart failure patients.Methods:Four healthy volunteers and four heart failure patients were selected to undergo 18F-FPMBBG positron emission tomography/computed tomography(PET/CT)dynamic imaging,the radioactivity distribution characteristics of 18F-FPMBBG in the heart and adjacent organs of the two groups were observed,and the uptake of 18F-FPMBBG by the left ventricular myocardium was compared in the two groups.Results:No adverse effects were observed in all subjects after intravenous injection of 18F-FPMBBG.In healthy volunteers,the heart uptake was rapid and stable,lung uptake was very low,and the blood pool and liver clearance were fast.The heart/liver uptake ratios at 30,60,and 90 minutes after injection were 2.33±0.81,3.29±0.90 and 3.80±1.07,respectively.The average standard uptake value(SUVmean)of 18F-FPMBBG in the heart failure group was significantly lower than that in the healthy volunteer group(P=0.003).The washout rate(WR)was significantly higher in the heart failure group([16.53±2.76]%vs.[3.88±4.51]%,P=0.003).Conclusions:18F-FPMBBG showed good imaging and diagnostic effects in the preliminary imaging of healthy subjects and heart failure patients,and it has the potential to become an ideal cardiac sympathetic nerve imaging agent.

Objective:To evaluate the clinical utility of dual-layer detector CT integrated with virtual monoenergetic imaging (VMI) and an orthopedic metal artifact reduction (O-MAR) algorithm in improving the image quality of patients after lumbar pedicle screw fixation surgery, and to analyze its impact on different types of artifacts and image quality of different tissues.Methods:The study was a prospective study, The study enrolled patients who underwent lumbar pedicle screw fixation at West China Hospital of Sichuan University between March and September 2024. All patients underwent lumbar CT scans using a dual-layer detector system, and four image sets were reconstructed. CLumbar routine scans were performed using dual-layer detector CT, and four image sets were reconstructed:onventional images (CI non-O-MAR), conventional images with O-MAR (CI O-MAR), virtual monoenergetic images (VMI non-O-MAR), and VMI with O-MAR (VMI O-MAR). Objective metrics including artifact index (AI), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were quantified, alongside subjective image quality assessment. One-way ANOVA or Friedman test were used to compare the objective evaluation indicators of image quality between VMI non-O-MAR and VMI O-MAR at different energy levels. Paired t-test or Wilcoxon signed-rank test was used for CI non-O-MAR/VMI non-O-MAR versus CI O-MAR/VMI O-MAR comparisons. Results:A total of 30 patients were included, and all underwent internal fixation with titanium alloy pedicle screws. Objective analysis revealed that in both high-and low-density artifact regions, the AI values of the VMI O-MAR group decreased with the increase of energy levels, and were significantly lower than those of the corresponding VMI non-O-MAR group, with a statistically significant difference (all P<0.001). When the energy level≥140 keV, the AI value of the VMI O-MAR group was simultaneously lower than that of the CI non-O-MAR group and the CI O-MAR group, with statistically significant differences (all P<0.05). The SNR and CNR on the vertebral bodies in the VMI non-O-MAR group and the VMI O-MAR group showed a decreasing trend with increasing energy levels, and were always lower than those in the CI group at high energy levels (100-180 keV) (all P<0.05). At high energy levels (100-180 keV), the SNR of VMI O-MAR in the intervertebral disc and intraspinal tissues was higher than that of the VMI non-O-MAR group, with statistically significant differences (all P<0.05). Compared to other groups, subjective analysis indicated that the 140 keV VMI combined with O-MAR group received the highest image quality scores ( P<0.05). Conclusions:The combined application of VMI and O-MAR technology effectively reduces metal artifacts in post-lumbar fixation CT images. The 140 keV VMI with O-MAR reconstruction provides superior image quality and enhances diagnostic confidence.

Objectives:To evaluate the imaging effects of the novel sympathetic nerve imaging agent 18F-FPMBBG in healthy volunteers and heart failure patients.Methods:Four healthy volunteers and four heart failure patients were selected to undergo 18F-FPMBBG positron emission tomography/computed tomography(PET/CT)dynamic imaging,the radioactivity distribution characteristics of 18F-FPMBBG in the heart and adjacent organs of the two groups were observed,and the uptake of 18F-FPMBBG by the left ventricular myocardium was compared in the two groups.Results:No adverse effects were observed in all subjects after intravenous injection of 18F-FPMBBG.In healthy volunteers,the heart uptake was rapid and stable,lung uptake was very low,and the blood pool and liver clearance were fast.The heart/liver uptake ratios at 30,60,and 90 minutes after injection were 2.33±0.81,3.29±0.90 and 3.80±1.07,respectively.The average standard uptake value(SUVmean)of 18F-FPMBBG in the heart failure group was significantly lower than that in the healthy volunteer group(P=0.003).The washout rate(WR)was significantly higher in the heart failure group([16.53±2.76]%vs.[3.88±4.51]%,P=0.003).Conclusions:18F-FPMBBG showed good imaging and diagnostic effects in the preliminary imaging of healthy subjects and heart failure patients,and it has the potential to become an ideal cardiac sympathetic nerve imaging agent.

Objective:To evaluate the clinical utility of dual-layer detector CT integrated with virtual monoenergetic imaging (VMI) and an orthopedic metal artifact reduction (O-MAR) algorithm in improving the image quality of patients after lumbar pedicle screw fixation surgery, and to analyze its impact on different types of artifacts and image quality of different tissues.Methods:The study was a prospective study, The study enrolled patients who underwent lumbar pedicle screw fixation at West China Hospital of Sichuan University between March and September 2024. All patients underwent lumbar CT scans using a dual-layer detector system, and four image sets were reconstructed. CLumbar routine scans were performed using dual-layer detector CT, and four image sets were reconstructed:onventional images (CI non-O-MAR), conventional images with O-MAR (CI O-MAR), virtual monoenergetic images (VMI non-O-MAR), and VMI with O-MAR (VMI O-MAR). Objective metrics including artifact index (AI), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were quantified, alongside subjective image quality assessment. One-way ANOVA or Friedman test were used to compare the objective evaluation indicators of image quality between VMI non-O-MAR and VMI O-MAR at different energy levels. Paired t-test or Wilcoxon signed-rank test was used for CI non-O-MAR/VMI non-O-MAR versus CI O-MAR/VMI O-MAR comparisons. Results:A total of 30 patients were included, and all underwent internal fixation with titanium alloy pedicle screws. Objective analysis revealed that in both high-and low-density artifact regions, the AI values of the VMI O-MAR group decreased with the increase of energy levels, and were significantly lower than those of the corresponding VMI non-O-MAR group, with a statistically significant difference (all P<0.001). When the energy level≥140 keV, the AI value of the VMI O-MAR group was simultaneously lower than that of the CI non-O-MAR group and the CI O-MAR group, with statistically significant differences (all P<0.05). The SNR and CNR on the vertebral bodies in the VMI non-O-MAR group and the VMI O-MAR group showed a decreasing trend with increasing energy levels, and were always lower than those in the CI group at high energy levels (100-180 keV) (all P<0.05). At high energy levels (100-180 keV), the SNR of VMI O-MAR in the intervertebral disc and intraspinal tissues was higher than that of the VMI non-O-MAR group, with statistically significant differences (all P<0.05). Compared to other groups, subjective analysis indicated that the 140 keV VMI combined with O-MAR group received the highest image quality scores ( P<0.05). Conclusions:The combined application of VMI and O-MAR technology effectively reduces metal artifacts in post-lumbar fixation CT images. The 140 keV VMI with O-MAR reconstruction provides superior image quality and enhances diagnostic confidence.

Objective To characterize neurological alterations associated with structural bowel damage in patients with Crohn's disease(CD)through radiomics-assisted neurophenotyping,utilizing multiparametric brain MRI.Methods This prospective study enrolled patients with CD who underwent brain MRI,MR enterography,and ileocolonoscopy within one week.The Lémann Index was used to quantitatively assess cumulative structural bowel damage.CD patients were stratified into two groups based on a cutoff value of 4.8:those with bowel damage(LI>4.8)and those without bowel damage(LI≤4.8).A neurophenotype model was developed to characterize the neural changes associated with bowel damage in CD.Key features were selected from first-order features extracted from multiparametric brain MRI in the training cohort and validated in an independent test cohort.Results The final study population comprised 109 patients,including 51 individuals with bowel damage and 58 without bowel damage.The neurophenotype model scores were 0.785(95%CI:0.506～0.945)in the bowel damage group and 0.155(95%CI:0.093～0.394)in the non-bowel damage group,showing a statistically significant difference between the two groups(P<0.001).The developed model exhibited strong discriminative performance,with area under the receiver operating characteristic curve(AUC)values ranging from 0.824 to 0.918 across the training,vali-dation,and test cohorts(all P<0.05).Conclusion Our radiomics-assisted neurophenotype analysis reveals neural alterations in CD patients with bowel damage,which may indicate extraintestinal manifestations associated with cumulative intestinal injury.

Objective To characterize neurological alterations associated with structural bowel damage in patients with Crohn's disease(CD)through radiomics-assisted neurophenotyping,utilizing multiparametric brain MRI.Methods This prospective study enrolled patients with CD who underwent brain MRI,MR enterography,and ileocolonoscopy within one week.The Lémann Index was used to quantitatively assess cumulative structural bowel damage.CD patients were stratified into two groups based on a cutoff value of 4.8:those with bowel damage(LI>4.8)and those without bowel damage(LI≤4.8).A neurophenotype model was developed to characterize the neural changes associated with bowel damage in CD.Key features were selected from first-order features extracted from multiparametric brain MRI in the training cohort and validated in an independent test cohort.Results The final study population comprised 109 patients,including 51 individuals with bowel damage and 58 without bowel damage.The neurophenotype model scores were 0.785(95%CI:0.506～0.945)in the bowel damage group and 0.155(95%CI:0.093～0.394)in the non-bowel damage group,showing a statistically significant difference between the two groups(P<0.001).The developed model exhibited strong discriminative performance,with area under the receiver operating characteristic curve(AUC)values ranging from 0.824 to 0.918 across the training,vali-dation,and test cohorts(all P<0.05).Conclusion Our radiomics-assisted neurophenotype analysis reveals neural alterations in CD patients with bowel damage,which may indicate extraintestinal manifestations associated with cumulative intestinal injury.

Objective To explore the feasibility of second-generation dual-layer detector spectral CT ab-dominal virtual non-contrast(VNC) for diagnosing fatty liver.Methods The imaging data of 128 patients with second-generation dual-layer detector spectral CT abdominal enhanced CT in West China Hospital of Si-chuan University from June 2022 to December 2022 were retrospectively analyzed.The CT values of the left lobe,right anterior lobe,right posterior lobe and spleen of all patients were measured on TNC,arterial stage VNC (A-VNC) and venous stage VNC (V-VNC) images.The difference value (L-S) and ratio value (L/S) between the CT value of liver and CT value of spleen were calculated.According to the threshold value of TNC image diagnosis of fatty liver in previous studies,the included cases were divided into two groups:fatty liver group and non-fatty liver group.The Mann-Whitney U test was used to compare the difference of quanti-tative parameters between the fatty liver group and non-fatty liver group.The efficiency of VNC in the diagno-sis of fatty liver was evaluated by the receiver operating characteristic (ROC) curve,and the difference be-tween ROC curves was compared with DeLong's test.The intra-group and inter-group correlation coefficient (ICC) values were used to evaluate the consistency of data measurement.Results The ICC values of intra-group and inter-group consistency of data ranged (0.835-0.986) and (0.810-0.978),respectively (P<0.05).The mean value of left lobe,right anterior lobe,right posterior lobe and triple lobe of liver and CT val-ue of spleen in A-VNC and V-VNC images were lower than those of TNC images,and the differences were statistically significant (P<0.05).The CT values of TNC,A-VNC,V-VNC,(L-S) values and (L/S) values of the non-fatty liver group were higher than those of the fatty liver group,and the differences were statistical-ly significant (P<0.05).The CT value,(L-S) value and (L/S) value of TNC,A-VNC and V-VNC images in the non-fatty liver group were higher than those in the fatty liver group,and the differences were statistically significant (P<0.05).The area under the curve (AUC) of CT values of A-VNC and V-VNC for the diagnosis of fatty liver all were 0.997,and their efficiencies for diagnosing fatty liver had no statistical difference (Z=0.407,P=0.684).AUC of A-VNC (L-S) and V-VNC (L-S) in the diagnosis of fatty liver was 1.000 and 0.981,respectively,and their efficiencies for diagnosing fatty liver had no statistical difference (Z=1.790,P=0.074).AUC of A-VNC (L/S) and V-VNC (L/S) in the diagnosis of fatty liver was 0.992 and 0.987,respec-tively,and their efficiencies for diagnosing fatty liver also had no statistical difference (Z=0.665,P=0.506). Conclusion The CT values of liver and spleen in VNC images reconstructed by second-generation dual-layer detector spectral CT are lower than TNC,but it is still feasible to diagnose fatty liver based on VNC images.

AIM: To optimize an orthopedic non-muscle invasive bladder cancer (NMIBC) model in nude mouse by comparing four different ways of cellular transplantation, and to evaluate the efficacy of drug by bladder instillation, so as to provide a stable and efficient animal model for the treatment of bladder cancer. METHODS: After disruption of bladder mucosa by dilute acid-alkali or silver nitrate, T24 cells were instilled into the nude mouse bladder. T24 cells were injected directly into the bladder with mechanical injury of bladder mucosa. T24 cells were injected into the bladder wall. On the 14th day after making models, the nude mice were sacrificed. And the bladder mass and histopathological changes of tumor (including bladder) was observe to confirm the formation of orthopedic bladder cancer. The dynamic changes of orthopedic bladder cancer were observed after injecting T24 cells into the bladder wall. Gemcitabine was used to verify the applicability of the model of injecting T24 cells into the bladder wall in vivo. RESULTS: No tumor was found in the bladder after intravesical instillation of T24 cells with dilute acid-alkali or silver nitrate treatment. With mechanical injury of bladder mucosa, all nude mice had tumors after injection T24 cells. But the number of tumors varied and often occurred at multiple sites. The tumor was found in the bladder of all nude mice by injecting T24 cells into bladder wall, and there was only one tumor. The tumor showed slow linear growth within 15 days and rapid linear growth from day 18 to 31. In vivo efficacy evaluation, gemcitabine 150 mg/kg intravesical perfusion could significantly inhibit the growth of NMIBC in nude mice replicated by direct injection of T24 cells into the bladder wall, and the tumor inhibition rate was 97.1%. CONCLUSION: The orthotopic NMIBC model can not be established with the bladder mucosa injuried by dilute acid-alkali or silver nitrate treatment. The number and size of orthotopic bladder cancer are different by mechanical injury of bladder mucosa. Injection of T24 cells into the bladder wall of nude mouse can successfully establish the orthotopic NMIBC model, which can be used for the evaluation of NMIBC therapeutic drugs.