目的 综合分析溃疡性结肠炎（ulcerative colitis，UC）相关scRNA-seq和RNA-seq数据集，探讨UC缓解期脾虚湿困证与活动期湿热阻滞证间的潜在分子机制，并挖掘潜在干预中药。方法 运用差异基因表达分析和韦恩图鉴定出UC缓解期脾虚湿困证和活动期湿热阻滞证相关基因及两者间的对话基因。通过京都基因与基因组百科全书（Kyoto encyclopedia of genes and genomes，KEGG）、基因集变异分析（gene set variation analysis，GSVA）及Spearman相关性分析深入探讨对话基因参与的生物过程及潜在功能。通过单细胞转录组分析探讨UC缓解期与活动期的差异情况及对话基因在其中的作用。基于循环算法构建UC缓解期脾虚湿困证向活动期湿热阻滞证发生发展的风险预测模型。运用外部数据集、动物实验与实时定量聚合酶链反应（real-time quantitative polymerase chain reaction，RT-PCR）进一步验证对话基因的表达情况。借助SoFDA数据库构建“基因-中医症状/现代医学症状”网络；借助TCMIP和COREMINE数据库预测对话基因的潜在靶向中药。结果 鉴定出31个UC缓解期脾虚湿困证相关基因，其主要富集在代谢相关途径；鉴定出160个UC活动期湿热阻滞证相关基因，其主要富集在炎症免疫相关途径。鉴定出22个UC缓解期脾虚湿困证与活动期湿热阻滞证之间的对话基因，上调对话基因与炎症免疫相关途径呈显著相关性，下调对话基因与代谢途径呈显著相关性。单细胞转录组分析显示，相比于正常对照及UC缓解期，UC活动期中B细胞占比上调；B细胞在UC活动期湿热阻滞证中作用贡献较大，而在UC缓解期脾虚湿困证中的作用贡献较小；UC活动期B细胞的受体信号通路活性明显高于UC缓解期；上调的对话基因CD55在B细胞中表达水平较高，CD55⁺B细胞与CD55⁻B细胞之间存在差异的细胞通讯及细胞代谢水平。6个风险预测基因（CD55、PCSK1、SERPING1、ACAT1、SLC26A2、HMGCS2）可以较为准确预测UC缓解期脾虚湿困证向UC活动期湿热阻滞证发展，动物实验及RT-PCR验证了其表达水平。通过数据库检索得到人参、黄芪、枸杞子等45味潜在靶向中药。结论 鉴定出22个关键对话基因，它们可能通过影响炎症免疫和代谢相关途径诱导UC缓解期脾虚湿困证向UC活动期湿热阻滞证发展。B细胞在UC缓解期脾虚湿困证向活动期湿热阻滞证发生发展过程中发挥重要作用。CD55可能通过影响炎症免疫和代谢相关途径，促进B细胞活性，从而促进UC缓解期脾虚湿困证向活动期湿热阻滞证发展。22个关键对话基因与UC相关中医症状和现代医学症状关联密切。

Objective To explore the potential molecular mechanism between spleen deficiency and dampness-stagnation syndrome in remission stage and dampness-heat stagnation syndrome in active stage of ulcerative colitis (UC) by comprehensively analyzing the scRNA-seq and RNA-seq data sets related to UC, and to explore the potential intervention of traditional Chinese medicine (TCM). Methods Differential gene expression analysis and venn diagram analysis were used to identify the related genes of spleen deficiency and dampness-stagnation syndrome in remission stage of UC, dampness-heat stagnation syndrome in active stage of UC and the crosstalk genes between them. Enrichment analysis of Kyoto encyclopedia of genes and genomes (KEGG) and gene set variation analysis (GSVA) and Spearman correlation analysis were used to explore the biological processes involved in crosstalk genes and their potential functions. Based on single-cell transcriptome analysis, we explored the differences between remission and active phases of UC and the role of crosstalk genes in them. Based on the circulation algorithm, a risk prediction model for the occurrence and development of UC from spleen deficiency and dampness-stagnation syndrome in remission stage to dampness-heat stagnation syndrome in active stage was constructed. Extraneous data, animal experiments and real-time quantitative polymerase chain reaction (RT-PCR) were used to further verify the expression of crosstalk genes. Based on SoFDA database, we constructed "gene-TCM symptom/modern medical symptom" network. Potential target traditional Chinese medicines (TCMs) of crosstalk genes were predicted by TCMIP and COREMINE databases. Results A total of 31 genes related to spleen deficiency and dampness-stagnation syndrome in remission stage of UC were identified, which were mainly enriched in metabolism-related pathways; A total of 160 genes related to dampness-heat stagnation syndrome in active stage of UC were identified, which were mainly enriched in inflammatory immune-related pathways. A total of 22 crosstalk genes were identified between spleen deficiency and dampness-stagnation syndrome in remission stage and dampness-heat stagnation syndrome in active stage of UC. Upregulating crosstalk genes were significantly correlated with inflammatory immune pathways, and downregulating crosstalk genes were significantly correlated with metabolism-related pathways. Single-cell transcriptome analysis revealed the proportion of B cells in the active phase was upregulated compared to normal controls and remission phases; B cells play a greater role in dampness-heat stagnation syndrome in active stage of UC than that in spleen deficiency and dampness-stagnation syndrome in remission stage. The receptor signaling pathway activity of B cells in UC active stage was significantly higher than that in UC remission stage. CD55, an up-regulated crosstalk gene, was highly expressed in B cells. There were differences in cell-to-cell communication and cellular metabolism between CD55⁺B cells and CD55⁻B cells. Six risk predict genes (CD55, PCSK1, SERPING1, ACAT1, SLC26A2, HMGCS2) can accurately predict the development from spleen deficiency and dampness-stagnation syndrome in remission stage to dampness-heat stagnation syndrome in active stage of UC. Animal experiments and RT-PCR confirmed their expression. A total of 45 potential targeted TCMs such as Renshen (Ginseng Radix et Rhizoma), Huangqi (Astragali Radix) and Gouqizi (Lycii Fructus) through database retrieval were obtained. Conclusion This study identified 22 key crosstalk genes, which may induce the development of spleen deficiency and dampness-stagnation syndrome in remission stage to dampness-heat stagnation syndrome in active stage of UC by influencing inflammatory immune and metabolic related pathways. B cells play an important role in the occurrence and development process from spleen deficiency and dampness-stagnation syndrome in remission stage to dampness-heat stagnation syndrome in active stage of UC. CD55 may promote B cell activity by affecting inflammatory immune and metabolic pathway, thus promoting the development of spleen deficiency and dampness-stagnation syndrome in remission stage of UC to dampness-heat stagnation syndrome in active stage. A total of 22 key crosstalk genes are closely related to UC-related Chinese medicine symptoms and modern medical symptoms.

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广州市科技计划⁃市校（院）联合资助基础与应用基础研究项目（2023A03J0738）；广东省中医院朝阳人才科研专项资助（ZY2022KY10，ZY2022YL04）