Spermatogenesis is a highly ordered and spatiotemporally regulated developmental process in the male reproductive system, during which spermatogonial stem cells (SSCs), supported by the seminiferous tubule microenvironment, sequentially undergo mitosis, meiosis, and spermiogenesis to ultimately generate structurally intact spermatozoa. This complex process is accompanied by extensive transcriptional reprogramming, chromatin remodeling, and finely tuned post-transcriptional regulation. Precise control of RNA fate is therefore essential for maintaining the continuity and fidelity of spermatogenesis, and its disruption represents a major molecular basis of male infertility. N⁶-methyladenosine (m⁶A), the most abundant internal RNA modification in eukaryotes, has emerged as a critical regulator of post-transcriptional gene expression. m⁶A methyltransferases (“writers”) catalyze the addition of a methyl group to the N⁶ position of adenosine, m⁶A demethylases (“erasers”) remove the modification, and m⁶A-binding proteins (“readers”) recognize m⁶A-modified transcripts. Through the coordinated actions of these factors, m⁶A regulates transcript fate at multiple levels, including RNA splicing, nuclear export, stability, translation, and decay. Emerging evidence indicates that m⁶A-mediated regulation is essential across multiple stages of spermatogenesis, including SSC self-renewal and differentiation, meiotic progression, maintenance of chromosomal stability, and sperm morphogenesis. Beyond its intrinsic functions in germ cells, m⁶A also contributes to the regulation of the testicular microenvironment. In sertoli cells, m⁶A is involved in maintaining blood-testis barrier integrity, RNA processing, and paracrine signaling, thereby providing structural and metabolic support for germ cell development. In Leydig cells, m⁶A regulates steroidogenesis, particularly testosterone synthesis, and participates in cellular stress responses and metabolic homeostasis. Through these mechanisms, m⁶A indirectly influences spermatogenesis by modulating the functional state of testicular somatic cells, highlighting an integrated regulatory mode that combines cell-intrinsic and microenvironment-mediated effects. Notably, distinct classes of m⁶A regulators exhibit pronounced stage-specific functions and coordinated division of labor, collectively forming a multilayered and dynamic regulatory network. Writers often display dosage- and temporal window-dependent effects; erasers contribute to stage-specific demethylation and functional compensation; while readers function through a “switch-buffer” dual-layer architecture, and RNA-binding proteins (RBPs) participate in substrate selection and post-transcriptional regulation. Importantly, emerging evidence suggests that some m⁶A-related proteins can function through noncanonical mechanisms independent of m⁶A recognition, such as intrinsic RNA-binding activity, helicase function, or ribonucleoprotein complex assembly, thereby expanding the functional landscape of the m⁶A regulatory system. Dysregulation of m⁶A machinery can lead to multiple spermatogenic defects, including impaired SSC self-renewal, meiotic arrest, abnormal chromatin remodeling, and defective sperm formation, ultimately resulting in male infertility. Despite substantial advances, several critical questions remain unresolved, including the distinction between m⁶A-dependent and -independent mechanisms, the spatiotemporal dynamics of m⁶A modifications at single-cell resolution, and the coordination and antagonism among different regulatory factors. In this review, we systematically summarize the dual regulation of spermatogenesis by germ cell-intrinsic mechanisms and the testicular microenvironment, and delineate the molecular mechanisms and stage-specific functions of the dynamic m⁶A regulatory network. We further discuss the current limitations in the field and propose feasible experimental strategies for future investigation. Collectively, this work aims to provide a comprehensive framework for understanding the epitranscriptomic regulation of spermatogenesis and to offer theoretical insights into the pathogenesis and clinical management of male infertility.

Spermatogenesis is a highly ordered and spatiotemporally regulated developmental process in the male reproductive system, during which spermatogonial stem cells (SSCs), supported by the seminiferous tubule microenvironment, sequentially undergo mitosis, meiosis, and spermiogenesis to ultimately generate structurally intact spermatozoa. This complex process is accompanied by extensive transcriptional reprogramming, chromatin remodeling, and finely tuned post-transcriptional regulation. Precise control of RNA fate is therefore essential for maintaining the continuity and fidelity of spermatogenesis, and its disruption represents a major molecular basis of male infertility. N⁶-methyladenosine (m⁶A), the most abundant internal RNA modification in eukaryotes, has emerged as a critical regulator of post-transcriptional gene expression. m⁶A methyltransferases (“writers”) catalyze the addition of a methyl group to the N⁶ position of adenosine, m⁶A demethylases (“erasers”) remove the modification, and m⁶A-binding proteins (“readers”) recognize m⁶A-modified transcripts. Through the coordinated actions of these factors, m⁶A regulates transcript fate at multiple levels, including RNA splicing, nuclear export, stability, translation, and decay. Emerging evidence indicates that m⁶A-mediated regulation is essential across multiple stages of spermatogenesis, including SSC self-renewal and differentiation, meiotic progression, maintenance of chromosomal stability, and sperm morphogenesis. Beyond its intrinsic functions in germ cells, m⁶A also contributes to the regulation of the testicular microenvironment. In sertoli cells, m⁶A is involved in maintaining blood-testis barrier integrity, RNA processing, and paracrine signaling, thereby providing structural and metabolic support for germ cell development. In Leydig cells, m⁶A regulates steroidogenesis, particularly testosterone synthesis, and participates in cellular stress responses and metabolic homeostasis. Through these mechanisms, m⁶A indirectly influences spermatogenesis by modulating the functional state of testicular somatic cells, highlighting an integrated regulatory mode that combines cell-intrinsic and microenvironment-mediated effects. Notably, distinct classes of m⁶A regulators exhibit pronounced stage-specific functions and coordinated division of labor, collectively forming a multilayered and dynamic regulatory network. Writers often display dosage- and temporal window-dependent effects; erasers contribute to stage-specific demethylation and functional compensation; while readers function through a “switch-buffer” dual-layer architecture, and RNA-binding proteins (RBPs) participate in substrate selection and post-transcriptional regulation. Importantly, emerging evidence suggests that some m⁶A-related proteins can function through noncanonical mechanisms independent of m⁶A recognition, such as intrinsic RNA-binding activity, helicase function, or ribonucleoprotein complex assembly, thereby expanding the functional landscape of the m⁶A regulatory system. Dysregulation of m⁶A machinery can lead to multiple spermatogenic defects, including impaired SSC self-renewal, meiotic arrest, abnormal chromatin remodeling, and defective sperm formation, ultimately resulting in male infertility. Despite substantial advances, several critical questions remain unresolved, including the distinction between m⁶A-dependent and -independent mechanisms, the spatiotemporal dynamics of m⁶A modifications at single-cell resolution, and the coordination and antagonism among different regulatory factors. In this review, we systematically summarize the dual regulation of spermatogenesis by germ cell-intrinsic mechanisms and the testicular microenvironment, and delineate the molecular mechanisms and stage-specific functions of the dynamic m⁶A regulatory network. We further discuss the current limitations in the field and propose feasible experimental strategies for future investigation. Collectively, this work aims to provide a comprehensive framework for understanding the epitranscriptomic regulation of spermatogenesis and to offer theoretical insights into the pathogenesis and clinical management of male infertility.

ObjectiveThis study aims to investigate the action mechanism by which Xiaozheng Zhitong paste （XZP） alleviates bone cancer pain （BCP） by regulating programmed death protein 1 （PD-1）/programmed death-ligand 1 （PD-L1） pathway-induced osteoclast formation. MethodsThirty female C57BL/6 mice were randomly allocated into the following groups （n=6 per group）： normal control group， model group， low‑dose XZP group （31.5 g·kg^-1）， high‑dose XZP group （63 g·kg^-1）， and PD‑1 inhibitor （Niv） group. A bone cancer pain （BCP） model was established by injecting Lewis lung carcinoma cells. Mice in the normal control and model groups received topical application of a blank paste matrix at the wound site. Mice in the low‑ and high‑dose XZP groups were treated with XZP applied topically twice daily. Mice in the Niv group were topically administered the blank paste matrix and additionally received Niv via tail‑vein injection every two days. All interventions were continued for 21 days. During this period， behavioral tests were performed to assess mechanical， motor， and thermal nociceptive sensitivities. After 21 days， all mice were euthanized， and bone tissue from the operated side was collected for sectioning and preservation. Tartrate‑resistant acid phosphatase （TRAP） staining was used to evaluate osteoclast expression in the lesioned bone tissue. Immunohistochemistry was performed to detect the expression of Runt‑related transcription factor 2 （Runx2） in the lesioned bone tissue. Immunofluorescence was employed to assess the expression of PD‑1 and PD‑L1 in the lesioned bone tissue. ResultsCompared with the normal group， the model group showed significantly decreased limb mechanical withdrawal threshold， spontaneous paw flinching， and thermal withdrawal latency （P<0.01）， increased number of osteoclasts in the lesioned bone tissue （P<0.01）， and reduced expression of Runx2 （P<0.01）. Compared with the model group， the BCP mice in the XZP low-dose group， XZP high-dose group， and Niv group exhibited increased limb mechanical withdrawal threshold， movement scores， and thermal withdrawal latency （P<0.01）. The XZP low-dose group showed no significant changes in osteoclast number or Runx2 expression， while the XZP high-dose group and Niv group demonstrated significantly reduced osteoclast numbers （P<0.01） and significantly increased Runx2 expression （P<0.01）. In the lesioned bone tissue of BCP mice， the XZP low-dose group showed no significant decrease in the percentage of PD-1 expression， but a decrease in the percentage of PD-L1 expression （P<0.05）. In contrast， both the XZP high-dose group and the Niv group exhibited significant reductions in the percentages of PD-1 and PD-L1 expression （P<0.01）. ConclusionXZP alleviates the pain of mice with BCP by blocking the PD-1/PD-L1 pathway to inhibit osteoclastogenesis.

ObjectiveTo investigate the effects and underlying mechanisms of Xiaozheng Zhitong Paste （XZP） on bone cancer pain （BCP）. MethodsThirty female BALB/c mice were randomly divided into five groups： a Sham group， a BCP group， a BCP+low-dose XZP group， a BCP+high-dose XZP group， and a BCP+high-dose XZP + protease-activated receptor 2 （PAR2） agonist GB-110 group. BCP mice model was constructed by injecting Lewis lung carcinoma cells into the femoral cavity of the right leg， which was followed by being treated with XZP for 21 d. After 21 d， the mice were sacrificed. Nissl staining was used to evaluate the survival of spinal cord neurons. Immunofluorescence staining was conducted to localize ionized calcium-binding adapter molecule 1 （Iba1） and neuronal nuclear antigen （NeuN） in spinal cord tissue， thereby assessing microglial activation and neuronal survival. Enzyme-linked immunosorbent assay （ELISA） was employed to measure the levels of interleukin-1β （IL-1β）， tumor necrosis factor-α （TNF-α）， interleukin-6 （IL-6）， transforming growth factor-β （TGF-β）， interleukin-4 （IL-4）， and interleukin-10 （IL-10） in spinal cord tissue. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to detect mRNA expression levels associated with M1/M2 polarization of microglia. Western blot analysis was performed to examine the expression of proteins related to microglial polarization as well as those involved in the PAR2/nuclear factor kappa B （NF-κB）/NOD-like receptor protein 3 （NLRP3） signaling pathway in the spinal cord. ResultsCompared with the Sham group， the spinal cord neurons were damaged， the number of Nissl-positive spinal cord neurons in the spinal cord tissue was significantly reduced （P<0.01）， and the rate of NeuN-positive cells was significantly decreased （P<0.01）. The spinal cord microglia were activated， the inflammatory level of the spinal cord tissue was enhanced， and Iba1 staining was significantly enhanced （P<0.01）. The levels of IL-1β， TNF-α， IL-6， TGF-β， IL-4 and IL-10 were significantly increased （P<0.01）. The mRNA expressions of IL-1β， TNF-α and inducible nitric oxide synthase （iNOS） were significantly increased （P<0.01）， and the expression of PAR2， NLRP3， ASC and NF-κB p65 proteins in the spinal cord tissue of the BCP mice was significantly enhanced （P<0.01）. Compared with the BCP group， high-dose XZP treatment significantly increased the number of Nissl-positive spinal cord neurons in the BCP mice （P<0.01）， significantly enhanced the rate of NeuN-positive cells in the spinal cord tissue， and significantly weakened Iba1 staining （P<0.01）. In addition， the levels of IL-1β， TNF-α， and IL-6 were significantly decreased， while the levels of TGF-β， IL-4， and IL-10 were significantly increased （P<0.05， P<0.01）. The mRNA expression levels of IL-1β， TNF-α， and iNOS were decreased， whereas those of cluster of differentiation 206 （CD206）， arginase-1 （Arg-1）， and YM1/2 were significantly increased （P<0.05， P<0.01）. Low-dose and high-dose XZP treatment significantly decreased the expression of PAR2， NLRP3， ASC， and NF-κB p65 proteins in the spinal cord tissue （P<0.05， P<0.01）. These effects could all be significantly eliminated by the PAR2 agonist GB-110. ConclusionXZP can mitigate BCP in mice， which may be achieved through blocking the activated PAR2/NF-κB/NLRP3 pathway.

ObjectiveThe paper aims to investigate the action mechanism by which the Xiaozheng Zhitong paste （XZP） relieves bone cancer pain （BCP）. MethodsA model of mice with BCP was established by using Lewis tumor cells. The therapeutic effects of XZP， the ferroptosis inhibitor Ferrostatin-1 （Fer-1）， and the nuclear factor erythroid 2-related factor 2 （Nrf2） inhibitor Brusatol （Bru） on BCP were examined. Mice were randomly divided into the Sham operation group， BCP group， BCP+XZP-L group， BCP+XZP-H group， BCP+Fer-1 group， and BCP+XZP-H+Bru group， with six mice in each group. Pain behavior tests were conducted on the mice to assess pain levels. Colorimetric assays were employed to measure ferroptosis-related factors in serum and spinal cord tissue including Fe， malondialdehyde （MDA）， reactive oxygen species （ROS）， and superoxide dismutase （SOD）. Immunofluorescence staining was used to assess ROS production in spinal cord tissue. Transmission electron microscopy was used to observe the ultrastructure of mitochondria in lumbar spinal cord tissue. Quantitative real-time polymerase chain reaction （Real-time PCR） was employed to detect mRNA expression of Nrf2， heme oxygenase-1 （HO-1）， glutathione peroxidase 4 （GPX4）， and solute carrier family 7 member 11 （SLC7A11） in spinal cord neuron tissue. The protein expression of Nrf2， HO-1， GPX4， and SLC7A11 in spinal cord neurons was measured by Western blot. ResultsCompared with the Sham group， mice in the BCP group exhibited significantly reduced limb usage scores， mechanical foot withdrawal thresholds， and thermal foot withdrawal thresholds （P<0.01）. Serum and lumbar spinal cord tissue levels of Fe， MDA， and reactive oxygen species （ROS） were significantly elevated （P<0.05）， while superoxide dismutase （SOD） levels were significantly decreased （P<0.05）. Lumbar spinal cord mitochondrial structural damage was observed， and mRNA and protein expression of Nrf2， HO-1， GPX4， and SLC7A11 were significantly downregulated （P<0.01）. Compared with the BCP group， both low- and high-dose XZP groups improved the aforementioned pain behavioral indicators （P<0.05，P<0.01）， reduced ferroptosis-related biomarkers including Fe， MDA， and ROS levels （P<0.05）， increased SOD levels （P<0.05，P<0.01）， alleviated mitochondrial damage， and upregulated Nrf2， HO-1， GPX4， SLC7A11 mRNA and protein expression （P<0.05，P<0.01）. The high-dose XZP group exhibited comparable efficacy to Fer-1 in alleviating pain and inhibiting ferroptosis. Following Bru administration， XZP's effects on pain behavioral indicators， regulation of ferroptosis-related markers， mitochondrial structural protection， and activation of the Nrf2/HO-1/GPX4/SLC7A11 pathway were significantly reversed （P<0.05，P<0.01）. ConclusionExternal application of XZP alleviates pain symptoms in BCP mice by activating the Nrf2/HO-1/GPX4/SLC7A11 pathway， thereby inhibiting ferroptosis and neuronal damage in spinal cord neurons.

ObjectiveProtein-protein interactions (PPIs) are fundamental to the execution of biological functions within living cells. However, traditional biochemical methods, such as co-immunoprecipitation (Co-IP), often fail to capture transient, weak, or membrane-associated interactions due to the stringent detergent requirements for cell lysis. Proximity labeling (PL) has emerged in recent years as a transformative technology for mapping the proteomes of specific subcellular compartments and identifying dynamic interactomes in situ. Golgi protein 73 (GP73, also known as GOLPH2), a resident type II Golgi transmembrane protein, is a well-recognized clinical biomarker for liver diseases, including hepatocellular carcinoma (HCC). Despite its clinical significance, the comprehensive physiological and pathological functions of GP73 remain partially understood. This study aims to establish an APEX2-mediated proximity labeling system specifically targeting GP73 to map its interactome in a living cellular environment, thereby providing new insights into its molecular roles and regulatory mechanisms. MethodsTo achieve spatial specificity, we first constructed a stable cell line expressing a fusion protein consisting of GP73 and the engineered soybean peroxidase APEX2. The localization of the GP73-APEX2 fusion protein was validated to ensure it correctly targeted the Golgi apparatus. The proximity labeling reaction was initiated by incubating the cells with biotin-phenol (BP) for 30 min, followed by a brief (1 min) treatment with1 mmol/L hydrogen peroxide (H₂O₂). This catalytic reaction converts BP into highly reactive, short-lived biotin-phenoxyl radicals that covalently attach to endogenous proteins within a small labeling radius of the GP73-APEX2 enzyme. Subsequently, the cells were quenched, and biotinylated proteins were enriched using high-affinity streptavidin-coated magnetic beads. The captured “neighbor” proteins were subjected to on-bead digestion and analyzed via liquid chromatography-tandem mass spectrometry (LC-MS/MS) for high-throughput identification. Rigorous bioinformatics analysis, including Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and protein-protein interaction network mapping, was performed to interpret the biological significance of the identified candidates. ResultsOur results demonstrate the successful establishment of a robust and sensitive APEX2-based proximity labeling system for GP73. We identified a total of 95 high-confidence interacting proteins that were significantly enriched in the GP73 proximity proteome compared to control groups. Bioinformatics analysis revealed that these interactors were predominantly associated with biological processes such as vesicular transport, protein localization, and, most notably, molecular functions related to “ribosome binding” and “translation regulation”. This suggested an unexpected role for the Golgi-resident GP73 in the cellular translation machinery. To validate these findings, we performed targeted biochemical assays which confirmed a direct interaction between GP73 and the subunits of the eukaryotic translation initiation factor 3 (eIF3) complex, specifically EIF3G and EIF3I. Furthermore, functional validation using the surface sensing of translation (SUnSET) assay—a non-radioactive method to monitor protein synthesis—revealed that the overexpression of GP73 significantly promoted global protein translation levels in the cell, whereas its depletion or inhibition resulted in reduced translation efficiency. ConclusionThis study successfully utilized APEX2-mediated proximity labeling to provide the first systematic map of GP73 interactome in living cells. Our findings uncover a novel, unconventional function of GP73 as a regulator of cellular protein translation, likely mediated through its interaction with the eIF3 complex. This discovery significantly broadens our understanding of the biological roles of GP73 beyond its traditional function in the Golgi apparatus and suggests that it may act as a bridge between Golgi-related trafficking and the protein synthesis machinery. Furthermore, the technical framework established in this study provides a valuable template for investigating other complex organelle-associated protein networks and resolving transient macromolecular interactions in various physiological and pathological contexts.

Hepatic alveolar echinococcosis is a highly invasive zoonotic parasitic disease with poor prognosis. Surgical intervention serves as the pivotal approach to achieve radical cure and improve the prognosis of hepatic alveolar echinococcosis patients. In recent years, with the popularization of the concept of precision surgery and the development of the multidisciplinary diagnosis and treatment model, the surgical treatment strategies for hepatic alveolar echinococcosis have been continuously enriched, and the selection of surgical procedures has become increasingly diversified. Although key surgical techniques such as radical hepatectomy, autologous liver transplantation and allogeneic liver transplantation have achieved remarkable progress in clinical application, many insurmountable challenges still remain. Therefore, by sorting out the latest evidence-based advances in the field of surgical treatment for hepatic alveolar echinococcosis, this article focuses on discussing the application status and bottlenecks of radical hepatectomy, autologous liver transplantation and allogeneic liver transplantation in hepatic alveolar echinococcosis, aiming to provide a reference for the clinical treatment of hepatic alveolar echinococcosis.

ObjectiveTo investigate the role of interleukin （IL）-17A in acute inhalational pneumonia induced by the highly drug-resistant and hypervirulent Staphylococcus aureus strain USA300-R in mice. MethodsAn acute inhalational pneumonia model was established in mice using an aerosolized pulmonary delivery technique. RNA sequencing （RNA-seq） and enzyme-linked immunosorbent assay （ELISA） were employed to examine the expression dynamics of Il17a mRNA and IL-17A protein， respectively， in the lungs of infected mice. Il17a knockout （Il17a^-/-） mice were generated using CRISPR/Cas9 gene editing technology. The survival rate， body weight， bacterial load in lung tissue， and histopathological changes were compared between Il17a^-/- and wild-type （WT） mice following inhalational infection with USA300-R. Results12 hours after USA300-R infection， compared to pre-infection， the expression level of Il17a mRNA in lung tissue and the level of IL-17A protein in bronchoalveolar lavage fluid （BALF） increased by approximately 50-fold （P<0.01） and 6-fold （P<0.001）， respectively. Compared to WT mice， Il17a^-/- mice exhibited approximately 10-fold higher bacterial loads in lung tissue at both 12 and 24 hours post-infection （P<0.001， P<0.05）. However， they showed significantly attenuated lung histopathological injury， reduced alveolar wall thickening， markedly decreased neutrophil infiltration， and an approximately 50% improvement in survival rate （P<0.05）. ConclusionIn acute Staphylococcus aureus USA300-R inhalational pneumonia， IL-17A contributes to bacterial clearance by recruiting neutrophils； however， excessive neutrophil infiltration exacerbates pulmonary inflammation and injury， reduces survival rates， and represents a potential therapeutic target.

Objective: To identify early clinical predictors associated with dysphagia and delayed swallowing recovery in patients with traumatic brain injury (TBI). Methods: In this retrospective study, we enrolled adult TBI patients admitted to the rehabilitation unit of a tertiary medical center between June 2019 and June 2023. Data on baseline characteristics, neurological status, imaging findings, and rehabilitation-related variables were collected. Swallowing function was assessed using two indicators: (1) nasogastric (NG) tube retention and (2) the Functional Oral Intake Scale (FOIS) scores at 1, 4, and 12 weeks post-injury. Regression analyses were conducted to identify predictors associated with dysphagia and swallowing recovery. Results: A total of 160 patients were included. At 1 week post-injury, longer intensive care unit (ICU) stay, poor initial sitting balance and use of sedative medication in ICU were associated with NG tube retention. At 4 weeks, lower initial Rancho Los Amigos Scale (RLAS) scores, immobility-related complications, longer hospitalization, and temporal lobe hematomas were associated with persistent NG tube dependence. By 12 weeks, older age, delayed ability to follow commands, and poor initial sitting balance remained associated with NG tube retention. FOIS outcomes were also associated with older age, delayed time to follow commands, impaired initial sitting balance, prolonged ICU stay, temporal lobe hematomas, lower initial RLAS scores, immobility-related complications, prolonged endotracheal tube placement and extended hospital stays. Conclusion Impaired cognitive status, poor physical function, immobility-related complications, and temporal lobe hematomas were key factors associated with dysphagia and delayed oral intake in individuals with TBI.

Objective To establish a flow cytometry method for detecting C1s protein on platelet surface and preliminarily explore its potential application value in the auxiliary diagnosis of primary immune thrombocytopenia(ITP).Methods C1s-conjugated 2 μm car-boxylated magnetic beads(C1s beads)were prepared and used as quality control particles.Fluorescein isothiocyanate(FITC)-labeled anti-C1s antibody was employed as the detection antibody to develop a flow cytometric assay for detecting C1s protein expression on platelets.The intra-assay and inter-assay precision,as well as the dilution linearity of the method,were evaluated.Subsequently,the expression levels of C1 s protein on the surface of platelets were compared among the ITP group,the non-ITP thrombocytopenia group,and the healthy control group.Results Light microscopy showed that both unconjugated carboxylated magnetic beads(blank beads)and C1s-conjugated beads were uniformly dispersed without aggregation.Under fluorescence microscopy,C1s beads exhibited strong yellow-green fluorescence,whereas the blank beads showed no fluorescence signal.The established flow cytometry assay exhibited ac-ceptable precision,with intra-assay coefficient of variation(CV)values of 7.02％,7.12％,and 3.91％for low,medium,and high con-centrations of C1s beads,respectively,and inter-assay CV values of 13.49％,6.15％,and 0.78％,respectively.The dilution linearity was satisfactory,coefficient of determination(R2)=0.998 8.Clinical sample testing revealed that the proportion of C1s-positive plate-lets in ITP group(2.56±0.79)％was significantly higher than that in healthy control group(0.23±0.18)％and the non-ITP thrombo-cytopenia control group(0.22±0.10)％,with statistically significant differences(both P＜0.05).Conclusion This study successfully established a stable and reliable flow-cytometry method for quantifying C1s expression on platelet surface and preliminarily demonstrated that C1s expression is significantly elevated on platelets of ITP patients,suggesting that C1s could serve as a potential auxiliary diag-nostic marker for ITP.