In recent years， traditional Chinese medicine （TCM） has achieved significant progress in the treatment of inflammatory bowel disease （IBD）. A comprehensive literature search was conducted covering the period from January 1， 2010， to December 30， 2024， across Chinese databases including China National Knowledge Infrastructure （CNKI）， Wanfang Data， VIP China Science and Technology Journal Database， and the Chinese Biomedical Literature Service System， as well as international databases such as PubMed， Web of Science， and Embase. The clinical applications and mechanistic studies of TCM in IBD were systematically reviewed. The current status of TCM research on the etiology and pathogenesis of IBD， innovative clinical practices， and multimodal therapeutic approaches， including Chinese herbal formulas， single herbs or active compounds， acupuncture， herbal retention enema， and acupoint application， were summarized， together with their synergistic effects when combined with western medical treatments. The development and application of Chinese patent medicines for IBD are undergoing a profound transition from efficacy validation to mechanistic exploration. Mechanistic studies on the effects of TCM in IBD mainly focus on regulating gut microbiota homeostasis， repairing the intestinal mucosal barrier， and modulating intestinal immune balance. Furthermore， future research directions for TCM-based IBD management are proposed， including the establishment of TCM diagnostic and treatment models， expanding integrated applications of external and internal TCM therapies， innovating personalized treatment strategies， and advancing drug development. These efforts aim to provide insights for the standardized and precision-oriented development of TCM in the diagnosis and treatment of IBD.

Purpose: Due to the preservation of the entire stomach after endoscopic resection, the occurrence of metachronous gastric cancer (MGC) remains a possibility. In this study, we investigated the incidence and risk factors for MGC in patients with early gastric cancer who underwent endoscopic submucosal dissection (ESD) and successfully eradicatedHelicobacter pylori. Materials and Methods: A retrospective analysis was conducted of 1,191 patients who underwent ESD and successfully eradicated H. pylori at the Affiliated Drum Tower Hospital of Nanjing University. Endoscopic surveillance was performed at 3, 6, and 12 months post-resection, and annually thereafter. MGC was defined as the development of a new cancer at a site other than the primary gastric cancer site, at least 1 year after the initial endoscopic resection. Results: A total of 77 patients were diagnosed with MGC during a median follow-up of 41.5 months. Kaplan-Meier analysis showed a 5-year cumulative incidence of MGC of 9.4% after successful H. pylori eradication. Multivariate analysis of the training set using Cox proportional hazards models identified male sex, severe atrophic gastritis, multiple gastric cancers before H. pylori eradication, and smoking history as independent risk factors for MGC.The nomogram exhibited favorable discrimination, with area under the curves of 0.767 and 0.822 in the training set and 0.724 and 0.745 in the testing set at 3 and 5 years, respectively. Conclusions Patients with gastric cancer who undergo endoscopic resection, even after successful H. pylori eradication, should undergo annual and continuous endoscopic surveillance for MGC.

OBJECTIVE To investigate the mechanism of Xibining Ⅱ formula in alleviating synovial inflammation and fibrosis in knee osteoarthritis （KOA） rats based on Janus kinase 2 （JAK2）/signal transducer and activator of transcription 3 （STAT3） pathway. METHODS Seventy-five male SD rats were randomly divided into sham operation group （Sham group）， KOA group， Xibining Ⅱ low-dose group （XBNⅡ-L group， 4 g/kg）， Xibining Ⅱ high-dose group （XBNⅡ-H group， 8 g/kg）， and Xibining Ⅱ high-dose combined with STAT3 activator Colivelin trifluoroacetate （C-TFA） group [C-TFA group， 8 g/kg Xibining Ⅱ+ 1.0 mg/（kg·d） C-TFA]， with 15 rats in each group. Except for the Sham group， the KOA model was established by anterior cruciate ligament transection in the other groups. After successful modeling， each group was given corresponding drugs by intragastric administration and （or） intraperitoneal injection once daily for 28 consecutive days. After the last medication， the pathological changes of synovial tissue of knee joint in each group were evaluated and the indicators were calculated. The levels of serum inflammatory factors were detected. The positive expressions of phosphorylated JAK2 （p-JAK2） and phosphorylated STAT3 （p-STAT3） in synovial tissue of the knee joint were detected. The expressions of JAK2/STAT3 pathway-related proteins and mRNAs in synovial tissue were detected. RESULTS Compared with the Sham group， the synovial lining cells in the KOA group showed significant proliferation and disordered arrangement； the Krenn score， fibrosis ratio， positive area percentage of p-JAK2 and p-STAT3， p-JAK2/JAK2 and p-STAT3/STAT3， protein expression of Collagen-Ⅰ and α -smooth muscle actin， the mRNA expression of JAK2， STAT3， Collagen-Ⅰ and α -smooth muscle actin， as well as serum levels of interleukin-1β and interleukin-18 were significantly increased （ P ＜0.05）. Compared with the KOA group， the above pathological changes were significantly improved in each dose group of Xibining Ⅱ formula， and all indicators were significantly decreased （ P ＜0.05）， with the XBNⅡ-H group showing better effects than the XBNⅡ-L group （ P ＜0.05）. Compared with the XBNⅡ-H group， the above pathological damages were aggravated in the C-TFA group， and all indicators were significantly worsened （ P ＜0.05）. CONCLUSIONS Xibining Ⅱ formula can alleviate synovial inflammation and fibrosis in KOA rats， and its mechanism may be related to inhibiting the activation of JAK2/STAT3 pathway.

Objective To investigate the development, role, and regulatory mechanism of macrophage efferocytosis in the liver of hosts infected with Schistosoma japonicum. Methods The expression of efferocytosis-related gene like efferocytosis receptors, efferocytosis-related bridging molecules,“eat me” signal and “don’t eat me” signal was detected in the livers of patients and mice infected with S. japonicum in the Gene Expression Omnibus (GEO) database. Ten wild-type (WT) male mice (6 ~ 8 weeks old, weighing 20 ~ 25 g) were randomly divided into a Schistosoma japonicum infection (SJ) group and a normal control (NC) group, with 5 mice in each group. The efferocytosis of neutrophils and T cells by liver macrophages was detected in mice from SJ group and NC group using flow cytometry and immunofluorescence assay, respectively. The expression of efferocytosis-related Mer receptor tyrosine kinase (MerTK) and Axl receptor tyrosine kinase (Axl) proteins was determined in mouse liver tissues using Western blotting assay, and the proportion of MerTK⁺ macrophages and the average fluorescence intensity of macrophage MerTK were detected in mouse livers using flow cytometry. Changes in liver granulomas and fibrosis were observed in mice infected with S. japonicum following injection of efferocytosis inhibitors, and S. japonicum-infected mice without injection of efferocytosis inhibitors served as controls. Bone marrow-derived macrophages (BMDMs) were isolated from macrophage scavenger receptor class A (SR-A) conditional knockout (CKO) and wild-type (WT) mice, and changes in apoptotic neutrophils were detected in SR-A CKO mouse macrophages in vitro using flow cytometry. Then, BMDMs was divided into the WT mono-culture group, the WT and apoptotic neutrophils co-culture group, the SR-A CKO mono-culture group, and the SR-A CKO and neutrophils co-culture group, and the expression of MerTK and Axl was quantified in vitro using Western blotting and real-time quantitative PCR (RT-qPCR) assays during neutrophil efferocytosis. The efferocytosis of neutrophils and T cells by mouse liver macrophages was detected in the SR-A CKO SJ group and the WT SJ group using flow cytometry and immunofluorescence assay, and the expression of MerTK and Axl proteins was determined in mouse liver tissues in both groups using Western blotting. In addition, the proportion of MerTK⁺ macrophages and the average fluorescence intensity of macrophage MerTK were detected in mouse livers in both groups using flow cytometry. Results Data from the GEO database showed that the expression of some efferocytosis receptors and efferocytosis-related bridging molecules, and “eat me” and “don’t eat me” signals all appeared a tendency towards a rise in livers of patients and mice in the SJ group relative to the NC group, suggesting that S. japonicum infection-induced liver diseases may be associated with efferocytosis. Flow cytometry detected higher proportions of Ly6G⁺ cells [(13.13 ± 0.45)% vs. (6.48 ± 0.25)%; t = 22.30, P < 0.05] and CD3⁺ cells [(7.60 ± 0.33)% vs. (3.30 ± 0.42)%; t = 13.98, P < 0.05] in mouse liver macrophages in the SJ group than in the NJ group, and the expression of MerTK protein [(2.30 ± 0.14) vs. (1.14 ± 0.46); t = 4.19, P < 0.05], the mean fluorescence intensity of macrophages [(160.67 ± 15.28) vs. (94.50 ± 19.61); t = 4.81, P < 0.05], and the proportion of MerTK⁺ macrophages [(20.78 ± 4.17)% vs. (6.85 ± 0.39)%; t = 6.57, P < 0.05] were significantly higher in mouse liver tissues in the SJ group than in the NC group. The Axl expression was lower in mouse liver tissues in the SJ group than in the NC group [(1.25 ± 0.08) vs. (1.93 ± 0.37); t = 2.79, P < 0.05], and the area of granulomas around single eggs [(9.18 ± 1.81) × 10⁴μm² vs. (5.24 ± 1.35) × 10⁴ μm²; t = 3.03, P < 0.05] and proportion of collagen fibers [(25.27 ± 3.99)% vs. (15.14 ± 4.02)%; t = 3.10, P < 0.05] were significantly greater in livers of S. japonicum-infected mice with injection of efferocytosis inhibitors than in mice without injection of efferocytosis inhibitors. The in vitro efferocytosis efficiency of BMDMs [(32.83 ± 3.17)% vs. (45.43 ± 2.34)%; t = 5.54, P < 0.05], and the proportions of Ly6G⁺ [(9.37 ± 0.48)% vs. (13.13 ± 0.72)%; t = 7.50, P < 0.05] and CD3⁺ cells [(4.95 ± 0.17)% vs. (7.64 ± 0.50)%; t = 8.87, P < 0.05] in liver macrophages post-infection with S. japonicum were significantly lower in SR-A CKO mice than in WT mice, and the expression of MerTK protein [(0.65 ± 0.25) vs. (1.96 ± 0.69); t = 3.10, P < 0.05], the average fluorescence intensity of macrophages [(138.33 ± 8.39) vs. (160.67 ± 15.28); t = 3.03, P < 0.05] and the proportion of MerTK⁺ macrophages [(13.17 ± 5.01)% vs. (22.63 ± 2.06)%; t = 3.56, P < 0.05] were significantly lower in mouse liver tissues in the SR-A CKO SJ group than in the WT group. Western blotting detected no significant difference in the Axl protein expression in mouse liver tissues between the SR-A CKO SJ group and the WT SJ group [(0.48 ± 0.07) vs. (0.68 ± 0.30); t = 1.09, P > 0.05]. There were significant differences in the relative MerTK mRNA and protein expression during efferocytosis of BMDMs among the WT monoculture group, the WT and apoptotic neutrophils co-culture group, the SR-A CKO mono-culture group, and the SR-A CKO and neutrophils co-culture group (F = 9.41 and 40.68, both P values < 0.05). In addition, there was a significant difference in the relative Axl mRNA expression during efferocytosis of BMDMs among the four groups (F = 13.62, P < 0.05); however, no significant difference was seen in the relative Axl protein expression (F = 1.27, P > 0.05). Conclusions Efferocytosis of liver macrophages is seen in mice infected with S. japonicum and inhibits liver fibrosis. SR-A may up-regulate the efficiency of macrophage efferocytosis through regulating the expression of efferocytosis receptors.

Retinal degenerative diseases are a group of blinding ocular disorders characterized by progressive and irreversible loss of retinal neural cells. They mainly include age-related macular degeneration and retinitis pigmentosa. At present, there are no curative clinical therapies capable of reversing the disease course. Patients have poor long-term visual prognosis, imposing a heavy public-health burden on families and society. Mesenchymal stem cell(MSC)-derived exosomes, as a novel cell-free therapeutic vector, have emerged as a research hotspot due to their low immunogenicity, no tumorigenic risk, and excellent tissue barrier penetration ability. This review systematically summarizes the core mechanisms of MSC-derived exosomes in regulating immune inflammation, inhibiting apoptosis, and promoting retinal neuroprotection and structural/functional recovery via miRNA and tsRNA, compares the efficacy differences and existing controversies among exosomes from different sources, and outlines the advances in intraocular delivery technologies and engineering modification strategies. Combined with preclinical and clinical data, the current bottlenecks and safety evidence for clinical translation were objectively described. Meanwhile, in view of the heterogeneity among existing studies, this review proposes future directions including standardized preparation and the establishment of efficacy evaluation systems, so as to provide theoretical references for the development of novel therapeutic strategies for retinal degenerative diseases.

ObjectiveThis study aimed to investigate the mechanism by which Luoshi Neiyi prescription treats endometriosis （EMs） through regulating ferroptosis， and to screen key metabolites and analyze their association with ferroptosis. MethodsClinical samples of normal endometrium from patients without EMs and eutopic and ectopic endometrium from EMs patients （10 cases each） were collected and divided into control group， eutopic group， and EMs group. Hematoxylin-eosin （HE） staining was performed to observe ectopic lesions of EMs. Immunohistochemistry was used to detect the expression of solute carrier family 7 member 11 （SLC7A11） and glutathione peroxidase 4 （GPX4）. Enzyme-linked immunosorbent assay （ELISA） was adopted to determine the levels of malondialdehyde （MDA）， ferrous ion （Fe²⁺）， GPX4 and glutathione （GSH） in endometrial tissues， as well as serum levels of Fe²⁺， GPX4 and GSH. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of SLC7A11， GPX4， transferrin receptor （TFR） and ferritin heavy chain 1 （FTH1）. In the in vitro experiment， primary stromal cells were isolated from ectopic lesions of EMs patients. Cell counting kit-8 （CCK-8） was used to determine the optimal concentration of drug-containing serum for intervention. The level of reactive oxygen species （ROS） was measured， and Real-time PCR was applied to detect ferroptosis-related indicators. In the animal experiments， an EM rat model was established， and the rats were randomly assigned to the sham operation group， EMs group， low-dose Luoshi Neiyi Formula group （7.87 g·kg^-1）， high-dose Luoshi Neiyi prescription group （15.74 g·kg^-1）， and danazol group （42 mg·kg^-1）. Untargeted metabolomics detection and pathway enrichment analysis were conducted on serum samples from patients and rats. Spearman correlation analysis was performed to assess the relationship between differential metabolites and ferroptosis indicators. The correlations between differential metabolites in patient endometrium and serum and key ferroptosis indicators （GPX4， Fe²⁺， MDA， GSH） as well as ferroptosis-related mRNAs （GPX4， SLC7A11， FTH1） were analyzed， and correlation heatmaps were generated accordingly. ResultsCompared with normal eutopic endometrium， ectopic lesions in EMs patients showed glandular disorganization and stromal fibrosis. In ectopic endometrium， the contents of MDA， ROS， and Fe²⁺ decreased， while GPX4 level increased， and the mRNA expression of SLC7A11 and GPX4 was upregulated （P<0.05， P<0.01）. In serum， the levels of GPX4 and Fe²⁺ were elevated， whereas the GSH level declined， suggesting abnormalities in ferroptosis-related pathways in ectopic lesions （P<0.05， P<0.01）. After intervention with Luoshi Neiyi prescription-containing serum， the intracellular ROS level in ectopic endometrial stromal cells was elevated， the mRNA expression of SLC7A11 and GPX4 was downregulated， and TFR mRNA expression was upregulated （P<0.05， P<0.01）. Metabolomics analysis revealed 1104 and 198 differential metabolites in EMs patients and EMs rats， respectively， compared with their corresponding control groups， and both low-dose and high-dose Luoshi Neiyi prescription were found to regulate this metabolic disturbance， with the core regulatory pathways mainly involving arginine and proline metabolism. Correlation analysis showed that the glycerophospholipids including PI（16∶0/17∶0） and PI［18∶2（9Z，12Z）］ were negatively correlated with GPX4 and positively correlated with MDA， while 17α-hydroxyprogesterone was positively correlated with GPX4， SLC7A11， and FTH1 q<0.05）. ConclusionLuoshi Neiyi prescription may systematically ameliorate disease-associated metabolic dysregulation via modulation of the serum arginine and proline metabolism pathway， and may regulate ferroptosis in ectopic lesions through a mechanism potentially linked to the serum glycerophospholipid and steroid metabolism pathways. Collectively， these findings provide experimental evidence for the clinical application of Luoshi Neiyi prescription.

ObjectiveThis study aimed to investigate the mechanism by which Luoshi Neiyi prescription treats endometriosis （EMs） through regulating ferroptosis， and to screen key metabolites and analyze their association with ferroptosis. MethodsClinical samples of normal endometrium from patients without EMs and eutopic and ectopic endometrium from EMs patients （10 cases each） were collected and divided into control group， eutopic group， and EMs group. Hematoxylin-eosin （HE） staining was performed to observe ectopic lesions of EMs. Immunohistochemistry was used to detect the expression of solute carrier family 7 member 11 （SLC7A11） and glutathione peroxidase 4 （GPX4）. Enzyme-linked immunosorbent assay （ELISA） was adopted to determine the levels of malondialdehyde （MDA）， ferrous ion （Fe²⁺）， GPX4 and glutathione （GSH） in endometrial tissues， as well as serum levels of Fe²⁺， GPX4 and GSH. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of SLC7A11， GPX4， transferrin receptor （TFR） and ferritin heavy chain 1 （FTH1）. In the in vitro experiment， primary stromal cells were isolated from ectopic lesions of EMs patients. Cell counting kit-8 （CCK-8） was used to determine the optimal concentration of drug-containing serum for intervention. The level of reactive oxygen species （ROS） was measured， and Real-time PCR was applied to detect ferroptosis-related indicators. In the animal experiments， an EM rat model was established， and the rats were randomly assigned to the sham operation group， EMs group， low-dose Luoshi Neiyi Formula group （7.87 g·kg^-1）， high-dose Luoshi Neiyi prescription group （15.74 g·kg^-1）， and danazol group （42 mg·kg^-1）. Untargeted metabolomics detection and pathway enrichment analysis were conducted on serum samples from patients and rats. Spearman correlation analysis was performed to assess the relationship between differential metabolites and ferroptosis indicators. The correlations between differential metabolites in patient endometrium and serum and key ferroptosis indicators （GPX4， Fe²⁺， MDA， GSH） as well as ferroptosis-related mRNAs （GPX4， SLC7A11， FTH1） were analyzed， and correlation heatmaps were generated accordingly. ResultsCompared with normal eutopic endometrium， ectopic lesions in EMs patients showed glandular disorganization and stromal fibrosis. In ectopic endometrium， the contents of MDA， ROS， and Fe²⁺ decreased， while GPX4 level increased， and the mRNA expression of SLC7A11 and GPX4 was upregulated （P<0.05， P<0.01）. In serum， the levels of GPX4 and Fe²⁺ were elevated， whereas the GSH level declined， suggesting abnormalities in ferroptosis-related pathways in ectopic lesions （P<0.05， P<0.01）. After intervention with Luoshi Neiyi prescription-containing serum， the intracellular ROS level in ectopic endometrial stromal cells was elevated， the mRNA expression of SLC7A11 and GPX4 was downregulated， and TFR mRNA expression was upregulated （P<0.05， P<0.01）. Metabolomics analysis revealed 1104 and 198 differential metabolites in EMs patients and EMs rats， respectively， compared with their corresponding control groups， and both low-dose and high-dose Luoshi Neiyi prescription were found to regulate this metabolic disturbance， with the core regulatory pathways mainly involving arginine and proline metabolism. Correlation analysis showed that the glycerophospholipids including PI（16∶0/17∶0） and PI［18∶2（9Z，12Z）］ were negatively correlated with GPX4 and positively correlated with MDA， while 17α-hydroxyprogesterone was positively correlated with GPX4， SLC7A11， and FTH1 q<0.05）. ConclusionLuoshi Neiyi prescription may systematically ameliorate disease-associated metabolic dysregulation via modulation of the serum arginine and proline metabolism pathway， and may regulate ferroptosis in ectopic lesions through a mechanism potentially linked to the serum glycerophospholipid and steroid metabolism pathways. Collectively， these findings provide experimental evidence for the clinical application of Luoshi Neiyi prescription.

Objective To analyze the clinical and epidemiological characteristics of influenza A(H3N2) in Tangshan City, Hebei Province, from 2023 to 2025, and to provide a scientific basis for precise prevention and control of local influenza. Methods The influenza-like cases and influenza outbreak cases in the influenza surveillance sentinel hospitals in Tangshan City from January 2023 to December 2025 were included in this study. The clinical characteristics and epidemic characteristics of H3N2 influenza patients were analyzed by descriptive epidemiological methods and chi-square test. Results A total of 11 567 influenza case samples were tested in the study, with a positive rate of 9.34% (1 080/11 567). Influenza A (H3N2) remained the predominant circulating subtype throughout the study period. January 2023 to February 2023 marked the tailing end of the previous season’s H3N2. Then, a minor peak dominated by H1N1 occurred from March to June, and H3N2 circulated again from October to December, peaking in December. From September 2024 to December 2024, H1N1 and H3N2 circulated concurrently, with H3N2 as the dominant strain, peaking in January of the following year. From March 2025 to September 2025, influenza activity remained at low level, and activity began to rise in October, with H1N1 peaking in November before declining, and H3N2 becoming the dominant strain in December. H3N2 mainly occurred in the 5-14 years old group. Cases in the 0–4-year-old group were primarily characterized by gastrointestinal symptoms, with high fever being common. Cases in the 5–59-year-old group were primarily characterized by systemic and respiratory symptoms, with better clinical outcomes. Cases aged 60 and older exhibited the highest rates of hospitalization, severe illness, and incidence of complications. Conclusion From 2023 to 2025, the influenza virus in Tangshan City, Hebei Province is dominated by influenza A (H3N2). The epidemic is characterized by a peak incidence during autumn and winter, co-circulation with H1N1, and fluctuations during the peak period. It is necessary to pay attention to the clinical management and prevention and control of influenza A (H3N2) in infants and the elderly.

Objective To investigate the relationship between 9 immunoinflammatory indicators derived from complete blood count and the severity of Mycoplasma pneumoniae pneumonia(MPP)in children of different ages.Methods Totally 2 132 children with MPP who were hospitalized in the Department of Pediatrics of The First Affiliated Hospital of Naval Medical University from Jul.1,2023,to Dec.31,2024 were enrolled,and were assigned to severe MPP(SMPP)or non-severe MPP(NSMPP)groups.According to age and gender 1∶1 matching,the children were assigned to 2 subgroups according to age(1-6 years old and＞6-16 years old).The basic data,laboratory examination and immunoinflammatory indicators from complete blood count of each group were collected and compared.The influencing factors of SMPP were analyzed by univariate and multivariate Cox proportional hazards regression models.Receiver operating characteristic curves were used to analyze the predictive value of indicators that showed statistically significant differences for SMPP.Results There were 220 patients with SMPP,accounting for 10.3%of MPP.In children aged 1-6 years,compared with the NSMPP group,the SMPP group had a longer hospital stay,higher platelet(PLT)count,platelet-to-lymphocyte ratio(PLR),neutrophil-to-lymphocyte ratio,derived neutrophil-to-lymphocyte ratio and systemic immune-inflammation index(all P＜0.05).PLR was an independent risk factor for SMPP(odds ratio=1.010,95%confidence interval[CI]1.003-1.018,P=0.007).The area under curve predicted by PLR for SMPP was 0.635(95%CI 0.560-0.711,P＜0.001),the best cut-off value was 125.04,and the corresponding sensitivity and specificity were 57.7%and 70.2%,respectively.All the children were assigned to low PLR group or high PLR group using the best cut-offvalue as the boundary,and the severe disease rate in the high PLR group was significantly higher than that in the low PLR group(65.9%[60/91]vs 37.6%[44/117],P＜0.001).All the children were assigned to Q1-Q4 groups by quartile,and the severe disease rate of the Q4 group(71.2%,37/52)was significantly higher than that of the Q1-Q3 group(all P＜0.05).In children aged＞6-16 years,compared with the NSMPP group,the PLT and PLR in the SMPP group were higher(both P＜0.05),but neither was an independent risk factor.All the children were assigned to low PLR group or high PLR group using the best cut-offvalue(137.03)as the boundary,and the severe disease rate in the high PLR group was significantly higher than that in the low PLR group(57.0%[77/135]vs 40.2%[39/97],P=0.011).All the children were assigned to Q1-Q4 groups by quartile,and the severe disease rate of the Q4 group(65.5%,38/58)was significantly higher than that of the Q1-Q3 group(all P＜0.05).Conclusion The immunoinflammatory indicators derived from complete blood count,especially PLR,have certain application value in predicting the severity of MPP children in different ages.

Objective:To construct a nanoparticle vaccine displaying the prefusion F (preF) protein of respiratory syncytial virus (RSV) using the I53-50 protein nanoparticle platform, and to systematically evaluate its immunogenicity and protective efficacy.Methods:The RSV preF trimer antigen was genetically fused to I53-50A and assembled in vitro with I53-50B to form preF-I53-50 nanoparticles, theoretically displaying 20 preF antigens per particle. The structure and purity were characterized by size-exclusion chromatography, SDS-PAGE, and negative-stain electron microscopy. BALB/c mice were intramuscularly immunized with varying doses (1 μg or 5 μg) of preF antigen or an equimolar amount of preF-I53-50 nanoparticles. Humoral immunity, B-cell responses, and protective efficacy were assessed following intranasal viral challenge.Results:The preF-I53-50 nanoparticles self-assembled into spherical structures (50-60 nm in diameter) with uniformly arrayed antigens. The nanoparticle vaccine enhanced RSV-specific IgG1 and IgG2a antibody responses, promoting a Th1-biased immune profile. At equimolar preF doses, the neutralizing antibody titers induced by 1 μg and 5 μg nanoparticle formulations were 2.8-fold and 2.3-fold higher, respectively, than those elicited by preF alone ( P<0.05). Notably, even the low-dose nanoparticle group outperformed the high-dose preF group (1.6-fold increase). Viral challenge experiments demonstrated that preF-I53-50 effectively suppressed pulmonary viral replication, mitigated pathological damage, and induced stronger germinal center and memory B-cell responses, suggesting enhanced B-cell affinity maturation and long-term immune memory. Conclusion:The preF-I53-50 vaccine improves the immunogenicity and protective efficacy of RSV preF through multivalent antigen display.