Objective:To analyze the proteomic profile changes in EV71-infected human glioblastoma U251 cells using pro-teomics technology,and to elucidate the potential molecular mechanisms underlying EV71-induced cytopathic effects.Methods:The EV71 virus with an MOI of 0.1 was inoculated into the human glioblastoma cell line U251 to establish an in vitro infection model.Cytopathic effects(CPE)were observed under an optical microscope,cell proliferation viability was assessed via CCK-8 assay,viral capsid protein VP1 expression was detected by Western blot and immunofluorescence,and high-throughput pro-teomics was employed to analyze differential protein expression profiles.Results:EV71 infection induced typical CPE in U251 cells,reduced proliferation and survival rates.Western blot and immunofluorescence confirmed elevated VP1 protein expression post-infection compared to controls.Proteomic analysis identified 6,326 proteins,with 103 upregulated and 106 downregulated.The GO function and KEGG pathway enrichment analyses indicated that the differentially expressed proteins were primarily en-riched in the lysosome pathway(downregulated),antigen processing and presentation(downregulated),and metabolic path-ways(upregulated).Conclusion:EV71 infection altered the proteome of U251 cells,with the underlying mechanisms possibly associated with the inhibition of lysosomal and antigen presentation functions,as well as the activation of cellular metabolic pathways.