{
  "abstract": "Objective Immune checkpoint inhibitors (ICIs) have revolutionised cancer treatment and patients’ survival. However, ICIs also cause severe immune-related adverse events, notably colitis, resulting in ICIs therapy discontinuation and tumour immunotherapy failure. This study investigates long myosin light chain kinase 1 (MLCK1), a known regulator of tight junction and gut permeability, to elucidate the mechanisms underlying ICI-mediated colitis and identify approaches to reduce this toxicity.Design This study employed an integrated approach, using clinical samples, in vivo models and in vitro organoid systems. Biopsies from patients with ICIs colitis were profiled using single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics. To recapitulate human ICIs colitis, we used a wild mouse microbiota (WildR) model, alongside various genetically modified and tumour-bearing models (including melanoma and MC38). Furthermore, mechanisms were investigated through organoid-immune cell co-cultures. Finally, surface plasmon resonance, microscale thermophoresis, full-spectrum flow cytometry, bulk RNA sequencing, immunostaining, ELISA and gut permeability assays were performed to comprehensively delineate the underlying molecular mechanism.Results Tight junction integrity was compromised in both human ICIs colitis and our WildR mouse model. We determined that this barrier dysfunction is driven by activation of the MLCK1-mediated leak pathway following ICI treatment. Using murine models, we identified tumour necrosis factor secreted by CD8 + and CD4+ T cells as an upstream regulator that induces colitis through this MLCK-dependent mechanism, as genetic deletion of MLCK preserved the tight junction structure and ameliorated the inflammation and ICIs colitis. Furthermore, a pharmacological screen identified the small molecule Epicatechin, which blocks MLCK1-FKBP8 interaction and inhibits the recruitment of MLCK1 to the perijunctional actomyosin ring and prevents the intestinal barrier loss. Finally, treatment with Epicatechin mitigated ICI-induced colitis without compromising the antitumour efficacy of the immunotherapy.Conclusions These findings suggest that MLCK1-dependent tight junction regulation is essential for ICIs colitis, positioning barrier restoration as a potential therapeutic strategy.",
  "authors": [
    {
      "affiliations": [
        "Laboratory of Molecular Biology, and Department of Biochemistry, School of Basic Medical Science, Innovation and Entrepreneurship Laboratory for College Students, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Lei Xiong"
    },
    {
      "affiliations": [
        "Laboratory of Molecular Biology, and Department of Biochemistry, School of Basic Medical Science, Innovation and Entrepreneurship Laboratory for College Students, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Jianshang Huang"
    },
    {
      "affiliations": [
        "Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China",
        "Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Inflammation and Immune-Mediated Diseases Laboratory of Anhui Province, Anhui Medical University, Hefei, Anhui, China",
        "School of Pharmacy, Anhui Medical University, Hefei, China"
      ],
      "name": "Yunsheng Dong"
    },
    {
      "affiliations": [
        "Department of Gastroenterology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Wei Han"
    },
    {
      "affiliations": [
        "Graduate Institute of Oral Biology, National Taiwan University, Taipei City, Taiwan"
      ],
      "name": "Wei-Ting Kuo"
    },
    {
      "affiliations": [
        "Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Wentao Xu"
    },
    {
      "affiliations": [
        "Innovation and Entrepreneurship Laboratory for College Students, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Yiran Han"
    },
    {
      "affiliations": [
        "Laboratory of Molecular Biology, and Department of Biochemistry, School of Basic Medical Science, Innovation and Entrepreneurship Laboratory for College Students, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Chenchen An"
    },
    {
      "affiliations": [
        "Laboratory of Molecular Biology, and Department of Biochemistry, School of Basic Medical Science, Innovation and Entrepreneurship Laboratory for College Students, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Rumeng Zhu"
    },
    {
      "affiliations": [
        "Innovation and Entrepreneurship Laboratory for College Students, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Nina Zhu"
    },
    {
      "affiliations": [
        "Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Hanqi Xia"
    },
    {
      "affiliations": [
        "Innovation and Entrepreneurship Laboratory for College Students, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Abduxukur Rahman"
    },
    {
      "affiliations": [
        "Laboratory of Molecular Biology, and Department of Biochemistry, School of Basic Medical Science, Innovation and Entrepreneurship Laboratory for College Students, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Sainan Tang"
    },
    {
      "affiliations": [
        "Laboratory of Molecular Biology, and Department of Biochemistry, School of Basic Medical Science, Innovation and Entrepreneurship Laboratory for College Students, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Chonggui Jiang"
    },
    {
      "affiliations": [
        "Laboratory of Molecular Biology, and Department of Biochemistry, School of Basic Medical Science, Innovation and Entrepreneurship Laboratory for College Students, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Junhao Zhao"
    },
    {
      "affiliations": [
        "Laboratory of Molecular Biology, and Department of Biochemistry, School of Basic Medical Science, Innovation and Entrepreneurship Laboratory for College Students, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Wangxiang Pei"
    },
    {
      "affiliations": [
        "Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Juan Wang"
    },
    {
      "affiliations": [
        "Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Xianda Wang"
    },
    {
      "affiliations": [
        "Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Jiayi Song"
    },
    {
      "affiliations": [
        "Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Zihan Wang"
    },
    {
      "affiliations": [
        "Department of Gastroenterology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Shanshan Wu"
    },
    {
      "affiliations": [
        "Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Inflammation and Immune-Mediated Diseases Laboratory of Anhui Province, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Hui Zhang"
    },
    {
      "affiliations": [
        "Department of Pathology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Honghai Xu"
    },
    {
      "affiliations": [
        "Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Inflammation and Immune-Mediated Diseases Laboratory of Anhui Province, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Baoming Wu"
    },
    {
      "affiliations": [
        "Chinese Academy of Sciences, Beijing, Fujian, China"
      ],
      "name": "Qiansheng Huang"
    },
    {
      "affiliations": [
        "Gastroenterology, Hepatology, and Nutrition, Boston Children’s Hospital, Boston, Massachusetts, USA",
        "Pediatrics, Harvard Medical School, Boston, Massachusetts, USA"
      ],
      "name": "Bin Bao"
    },
    {
      "affiliations": [
        "Department of Gastroenterology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Qiao Mei"
    },
    {
      "affiliations": [
        "Laboratory of Molecular Biology, and Department of Biochemistry, School of Basic Medical Science, Innovation and Entrepreneurship Laboratory for College Students, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Huaqing Zhu"
    },
    {
      "affiliations": [
        "The First People’s Hospital of Wuhu, Wannan Medical College, Wuhu, Anhui, China"
      ],
      "name": "Lanlan Hou"
    },
    {
      "affiliations": [
        "Indiana University School of Medicine, Indianapolis, Indiana, USA"
      ],
      "name": "Suthat Liangpunsakul"
    },
    {
      "affiliations": [
        "Department of Otorhinolaryngology-Head and Neck Surgery, Anhui Medical University, The Second People’s Hospital, Hefei, Anhui, China"
      ],
      "name": "Feng Cao"
    },
    {
      "affiliations": [
        "Department of Medicine II, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany"
      ],
      "name": "Honglei Weng"
    },
    {
      "affiliations": [
        "Department of Gastroenterology, Peking Union Medical College Hospital, Beijing, China"
      ],
      "name": "Bei Tan"
    },
    {
      "affiliations": [
        "Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA"
      ],
      "name": "Jerrold R Turner"
    },
    {
      "affiliations": [
        "Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China",
        "Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Inflammation and Immune-Mediated Diseases Laboratory of Anhui Province, Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Hua Wang"
    },
    {
      "affiliations": [
        "Laboratory of Molecular Biology, and Department of Biochemistry, School of Basic Medical Science, Innovation and Entrepreneurship Laboratory for College Students, Anhui Medical University, Hefei, Anhui, China",
        "Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China"
      ],
      "name": "Li Zuo"
    }
  ],
  "title": "Targeting MLCK1 uncouples immune checkpoint inhibitor-induced colitis from antitumour immunity",
  "uid": "b87682bb-987c-5984-8012-bd39f94aec1d"
}