Vascular biology
Abstract
Although mammals generally demonstrate limited regenerative capacity compared with amphibians, the digit tip retains remarkable regenerative potential, providing a useful model to study successful mammalian regeneration. This process involves coordinated immune cell activity, vascular remodeling, and tissue reconstruction, yet the molecular checkpoints controlling regenerative versus fibrotic outcomes remain poorly understood. In mammals, regeneration of the digit tip (P3) proceeds through myeloid cell migration, early osteoclast-mediated osteolysis of the distal bone, and subsequent blastema-mediated regeneration. Here we test the hypothesis that lymphatic vessels regulate regenerative capacity by modulating local immune cell dynamics and osteoclast function. Using a lymphatic system–specific reporter line, we discovered that lymphatic vessels grow toward the nail region from the ventral side of the digit during quiescence and after amputation. These lymphatics closely surround, but do not invade, the native or regenerated bone. Unexpectedly, genetic, pharmacological, and surgical inhibition of lymphangiogenesis accelerated early osteolysis through enhanced transition of myeloid cells to osteoclasts, resulting in faster and more robust regeneration. These findings reveal a mechanism linking lymphatic vessel, immune regulation, and bone remodeling, suggesting that targeted manipulation of lymphatics dynamics may enhance regenerative outcomes after musculoskeletal injury.
Authors
Neda Vishlaghi, Trisha K. Ghotra, Monisha Mittal, Ji Hae L. Choi, Sneha Korlakunta, Mingquan Yan, Janna L. Crossley, Danielle Griswold-Wheeler, Elnaz Ghotbi, Conan Juan, Shiri Gur-Cohen, Babak Mehrara, David A. Brown, Michael T. Dellinger, Lindsay A. Dawson, Benjamin Levi
Abstract
Human genetic studies have repeatedly associated ADAMTS7 with atherosclerotic cardiovascular disease. Subsequent investigations in mice demonstrated that ADAMTS7 is proatherogenic and induced in response to vascular injury. However, the cell-specific mechanisms governing ADAMTS7 proatherogenicity remain unclear. To determine which vascular cell types express ADAMTS7, we interrogated single-cell RNA sequencing of human carotid atherosclerosis and found ADAMTS7 expression in smooth muscle cells (SMCs), endothelial cells (ECs), and fibroblasts. We subsequently created SMC- and EC-specific Adamts7 conditional knockout and transgenic mice. Conditional knockout of Adamts7 in either cell type does not reduce atherosclerosis, whereas transgenic induction in either cell type increases atherosclerosis. In SMC transgenic mice, this increase coincides with an expansion of lipid-laden SMC foam cells and a decrease in fibrous cap formation. RNA-sequencing in Adamts7 overexpressing SMCs revealed an upregulation of lipid genes typically assigned to macrophages. Mechanistically, ADAMTS7 increases SMC oxLDL uptake through CD36, whose expression is upregulated by PU.1. ATAC-seq and motif analysis revealed increased chromatin accessibility at AP-1 enriched regions, consistent with AP-1 dependent remodeling of PU.1-regulated lipid-handling loci. In summary, ADAMTS7 promotes atherosclerosis by driving SMC foam cell formation through an AP-1/PU.1/CD36 regulatory axis.
Authors
Allen Chung, Lauren E. Fries, Hyun-Kyung Chang, Huize Pan, Alexander C. Bashore, Karissa Shuck, Caio V. Matias, Juliana Gomez Pardo, Jordan S. Kesner, Hanying Yan, Mingyao Li, Robert C. Bauer
Abstract
Atherosclerotic cardiovascular disease (ASCVD) remains a leading cause of death worldwide, with plaque instability being a major culprit. Phenotypic switching of vascular smooth muscle cells (VSMCs) is a central event in atherosclerosis, driving both plaque progression and stability, yet the underlying mechanisms are incompletely understood, limiting drug development targeting this process. Kinesin family member 13B (KIF13B) has been implicated in vascular biology, but its function in VSMCs is unknown. Here, we demonstrate that VSMC-specific deletion of Kif13b in mice overexpressing proprotein convertase subtilisin/kexin type 9 (PCSK9) exacerbates lesion development and impairs plaque stability, characterized by thinner fibrous caps and increased inflammation. Mechanistically, we identified that KIF13B facilitates the ubiquitination and proteasomal degradation of Krüppel-like factor 4 (KLF4) through the Potassium channel tetramerization domain containing 10 (KCTD10)-dependent pathway. This KIF13B/KCTD10 axis reduces KLF4 protein levels, thereby inhibiting the pro-inflammatory responses and fibroblast-like transition of VSMCs to preserve their contractile phenotype. Importantly, the adverse effects of Kif13b deficiency on atherogenesis were effectively rescued by the small-molecule KLF4 inhibitor Kenpaullone. Our results unveil a VSMC-specific atheroprotective role for KIF13B, define the KIF13B/KCTD10/KLF4 pathway as a key regulatory axis governing VSMC fate and plaque stability, and validate its therapeutic potential for treating advanced atherosclerosis.
Authors
Guolin Miao, Yufei Han, Jingxuan Chen, Yiran Liu, Ge Zhang, Shaotong Pei, Yinqi Zhao, Yitong Xu, Liwen Zheng, Zhaoling Li, Xiangru Liu, Sijing Shi, Xuya Kang, Yahan Liu, Ling Zhang, Wei Huang, Yuhui Wang, Junnan Tang, Erdan Dong, Xunde Xian
Abstract
The lymphatic system maintains tissue fluid balance, and FOXC2 mutations cause lymphoedema-distichiasis syndrome, which is characterized by lymphatic valve defects. Although oscillatory shear stress regulates FOXC2 expression, other extracellular regulators remain unclear. In this study, we identified LPA4 and LPA6, two Gα12/Gα13-coupled receptors for the bioactive lipid lysophosphatidic acid (LPA), as key regulators of FOXC2 expression and lymphatic valve development. Lymphatic endothelial cell (LEC)-specific Lpa4;Lpa6-deficient mice exhibited impaired lymphatic valve formation and maintenance, which resembled phenotypes of LEC-specific Foxc2-deficient mice, including abnormal lymphatic vessel patterning. Mechanistically, lymphatic endothelial Lpa4/Lpa6 ablation reduced FOXC2 expression in vitro and in vivo. NF-κB was found essential for LPA-induced FOXC2 expression through the LPA4/LPA6-Gα12/Gα13-Rho kinase signaling axis. Accordingly, pharmacological inhibition of NF-κB and Rho kinase impaired lymphatic valve maintenance in mice. These results suggested that lymphatic endothelial LPA4 and LPA6 synergistically regulate FOXC2 expression through NF-κB activation and play an important role in lymphatic valve formation and maintenance. Our findings provide a molecular basis for lymphatic vessel development with a therapeutic potential for targeting lymphatic-associated diseases.
Authors
Daisuke Yasuda, Nana Sato, Keisuke Yanagida, Tomomi Hashidate-Yoshida, Tomohiro Shiiya, Hideo Shindou, Atsuki Taira, Takashi Ebihara, Takao Shimizu, Masanori Hirashima, Seiya Mizuno, Satoru Takahashi, Satoshi Ishii
Abstract
Vessels encapsulating tumor clusters (VETC), a distinct vascular pattern in hepatocellular carcinoma (HCC), facilitates non-invasive metastasis in whole cluster. The interaction between VETC and tumor microenvironment requires exploration. Here, we found that compared to human Non-VETC-HCCs, VETC-tumors exhibited more PD1+CD8+ T cells and Tregs, especially TNFRSF4+Tregs and Ki67+Tregs which showed increased immunosuppressive and proliferative activity. Such immunosuppressive status was also detected in tumor emboli of VETC-HCCs, and Treg density in emboli was positively associated with metastatic cell proliferation. VETC-HCCs revealed abundance correlation, closer spatial proximity, and stronger immunosuppressive ligand-receptor interactions between TNFRSF4+Tregs/Ki67+Tregs and PD1+CD8+ T cells. Depleting Tregs in mice reduced PD1+CD8+ T cells in primary lesions, tumor emboli and metastatic foci of VETC-allografts, and attenuated allograft metastasis. TGF-β1 levels were upregulated in endothelial cells of VETC-HCCs and associated with TNFRSF4+Tregs/Ki67+Tregs enrichment. Disrupting VETC formation decreased endothelial TGF-β1 expression, and reduced TNFRSF4+Tregs/Ki67+Tregs, PD1+CD8+ T cells, Treg/CD8+ T cells ratio. Collectively, VETC may enhance Tregs’ activity via TGF-β1, while Tregs promote and sustain CD8+ T cell exhaustion through immune inhibitory ligand-receptor interaction, thereby shaping immunosuppressive microenvironment and enabling tumor cluster to carry such niche to disseminate. These findings disclose mechanisms of tumor immune microenvironment formation and provide rationales for precision medicine.
Authors
Bi-Yu Huang, Zheng-Qi Mi, Xiao-Yu Zhang, Yu-Chen Ji, Meng-Zhi Wu, Zi-Feng Cheng, Chen Xie, Shuai He, Jing Zhu, Jian-Hong Fang, Chong Wu, Bin-Kui Li, Yun-Fei YUAN, Limin Zheng, Shi-Mei Zhuang
Abstract
Lymphatics maintains fluid homeostasis, immune surveillance, and tissue integrity. Here, we identified the E26 transformation-specific (ETS) transcription factors Erg and Fli1 as essential, cooperative regulators of lymphatic integrity and function. Using inducible, lymphatic endothelial cell-specific deletion in mice, we demonstrated that combined loss of Erg and Fli1 in adults results in fatal lymphatic failure, including chylothorax, chylous ascites, and impaired lymphatic drainage. Single-cell transcriptomic analysis revealed that loss of Erg and Fli1 caused disrupted lymphatic heterogeneity and dysregulation of key lymphatic genes, including valve-specific gene profiles. Erg and Fli1 coordinated lymphatic-immune crosstalk by transcriptionally regulating C-C motif chemokine ligand 21 (Ccl21), which mediates dendritic cell trafficking. Their loss also induced pro-inflammatory and pro-thrombotic gene expression, further contributing to lymphatic dysfunction. During embryonic development, the co-deletion led to lymphatic mis-patterning and loss of valve-initiating lymphatic endothelial cell clusters. The impact of loss of Erg and Fli1 function on lymphatic development in mice is consistent with FOXC2 mutations in lymphedema-distichiasis syndrome or ERG gene variants underlying primary lymphoedema in humans. Moreover, Erg and Fli1 were required for regenerative lymphangiogenesis and lymphatic repair following injury in adults. Our findings establish Erg and Fli1 as core transcriptional regulators of lymphatic identity, integrity, and function.
Authors
Myung Jin Yang, Seok Kang, Seon Pyo Hong, Hokyung Jin, Jin-Hui Yoon, Cheolhwa Jin, Chae Min Yuk, Lidiya G Gebeyehu, Junho Jung, Sung-hwan Yoon, Hyuek jong Lee, Gou Young Koh
Abstract
Recent studies suggest that prediabetes is an independent risk factor for cardiovascular thrombotic events. However, the mechanisms that may promote platelet activation and thrombosis in prediabetes remain elusive. To determine mechanisms linking prediabetes and thrombosis as a function of age, we recruited prediabetic and normoglycemic Veterans in young and middle-age groups. Compared to normoglycemic subjects, platelets from those with prediabetes exhibited increased activation, mitochondrial-oxidant load, mitochondrial-membrane hyperpolarization, and greater thrombus formation ex vivo regardless of age. Preincubation of platelets with mitochondria targeted antioxidants such as superoxide dismutase (SOD) mimetic or Mito quinol (MitoQ), rescued this prothrombotic phenotype. These phenotypes were recapitulated in C57BL6/J mice exhibiting early onset of glucose intolerance when fed high fat (HF) diet for two weeks. Treatment of HF-fed mice with a SOD-mimetic or MitoQ, or genetic overexpression of catalase within mitochondria, not only lowered mitochondrial-oxidants, hyperpolarization, Ca2+ levels and platelet activation, but also protected against increased potential for carotid and pulmonary thrombosis. We also observed a bidirectional regulation of platelet activation by Ca2+ and mitochondrial oxidants. These findings support the idea that mitochondrial-oxidant dependent platelet activation induces a prothrombotic state in clinical prediabetes and preclinical models of short-term glucose intolerance and can be reversed by mitochondria-targeted antioxidants.
Authors
Azaj Ahmed, Pooja Yadav, Melissa Jensen, Katharine Geasland, Jagadish S. Swamy, Douglas R. Spitz, E. Dale Abel, Diana Jalal, Sanjana Dayal
Abstract
Authors
Amit Prabhakar, Eckart M.D.D. De Bie, Jacqueline T. DesJardin, Prajakta Ghatpande, Stefan Gräf, Luke S. Howard, S. John Wort, Colin Church, David G. Kiely, Emily Sumpena, Thin Aung, Shenrae Carter, Jasleen Kukreja, Steven Hays, John R. Greenland, Jonathan P. Singer, Michael Wax, Paul J. Wolters, Marc A. Simon, Mark Toshner, Giorgio Lagna, Akiko Hata
Abstract
Venous thromboembolism (VTE) is a leading cause of morbidity and mortality, with risk heightened in premenopausal women with obesity or use estrogen-based oral contraceptives. When both risk factors are present, the thrombosis risk increases substantially. Protein S (PS), an essential anticoagulant cofactor, is downregulated by both estrogen and obesity, but the molecular basis for this suppression remains poorly defined. We investigated the effect of estrogen and obesity on PS expression using plasma samples from 157 women stratified by BMI and contraceptive use, alongside 40 mice categorized as lean or obese with or without estrogen pellet treatment. The levels of PS were reduced by either estrogen or obesity alone, and the combined effect increased thrombin generation. In HepG2 hepatocytes, hypoxic conditions (1%–10% O2) mimicking obesity, with or without 17 β-estradiol, suppressed PROS1 transcription and promoter activity. ChIP confirmed direct binding of hypoxia-inducible factor 1α (HIF1α) to the PROS1 promoter, repressing gene expression. These findings define a mechanistic pathway through which estrogen and obesity converge to suppress PS synthesis, providing insight into the elevated thrombosis risk observed in women with obesity using estrogen-based contraceptives.
Authors
Mohammad A. Mohammad, Narender Kumar, Sonali Ghosh, Ashley Paysse, Claudia Leonardi, Vijaya Pilli, Ma Lorena Duhaylungsod, Eric Lazartigues, Diana C. Polania-Villanueva, Sadaf Nouman, Logan A. Barrios, Rima Chattopadhyay, Rafika Yasmin, Alaina Guilbeau, Manoj Kumar, Tina Nguyen, Jovanny Zabaleta, Li Li, Luis Del Valle, Mallory T. Barbier, Samarpan Majumder, Laurent O. Mosnier, Rinku Majumder
Abstract
Genetic factors are fundamental in the etiology of thoracic aortic aneurysm and dissection (TAAD), but the genetic cause is detected in only about 30% of cases. To define unreported TAAD-associated sequence variants, exome and gene panel sequencing was performed in 323 patients. We identified heterozygous CDKL1 variants [c.427T>C p.(Cys143Arg), c.617C>T p.(Ser206Leu), and c.404C>T p.(Thr135Met)] in 6 patients from 3 families with TAAD-spectrum disorders. CDKL1 encodes a protein kinase involved in ciliary biology. Amino acid substitutions were predicted to affect CDKL1 catalytic activity or protein binding properties. CDKL1 was expressed in vascular smooth muscle cells in normal and diseased human aortic wall tissue. Cdkl1 knockdown and transient knockout in zebrafish resulted in intersomitic vessel (ISV) malformations and aortic dilation. Co-injection of human CDKL1wildtype, but not CDKL1Cys143Arg and CDKL1Ser206Leu RNA, rescued ISV malformations. All variants affected CDKL1 kinase function and profiling data, and altered protein-protein binding properties, particularily with ciliary transport molecules. Expression of CDKL1 variants in heterologeous cells interfered with cilia formation and length, CDKL1 localization, and p38-MAPK and Vegf signaling. Our data suggest a role of CDKL1 variants in the pathogenesis of TAAD-spectrum disorders. The association between primary cilia dysregulation and TAAD expands our knowledge of the underlying molecular pathophysiology.
Authors
Theresa Nauth, Melanie Philipp, Sina Renner, Martin D. Burkhalter, Helke Schüler, Ceren Saygi, Kristian Händler, Bente Siebels, Alice Busch, Thomas Mair, Verena Rickassel, Sophia Deden, Konstantin Hoffer, Jakob Olfe, Thomas S. Mir, Yskert von Kodolitsch, Evaldas Girdauskas, Meike Rybczynski, Malte Kriegs, Hannah Voß, Thomas Sauvigny, Malte Spielmann, Malik Alawi, Susanne Krasemann, Christian Kubisch, Till J. Demal, Georg Rosenberger
Copyright © 2026 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)