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Nature Apr 2024The immune system has a critical role in orchestrating tissue healing. As a result, regenerative strategies that control immune components have proved effective. This is...
The immune system has a critical role in orchestrating tissue healing. As a result, regenerative strategies that control immune components have proved effective. This is particularly relevant when immune dysregulation that results from conditions such as diabetes or advanced age impairs tissue healing following injury. Nociceptive sensory neurons have a crucial role as immunoregulators and exert both protective and harmful effects depending on the context. However, how neuro-immune interactions affect tissue repair and regeneration following acute injury is unclear. Here we show that ablation of the Na1.8 nociceptor impairs skin wound repair and muscle regeneration after acute tissue injury. Nociceptor endings grow into injured skin and muscle tissues and signal to immune cells through the neuropeptide calcitonin gene-related peptide (CGRP) during the healing process. CGRP acts via receptor activity-modifying protein 1 (RAMP1) on neutrophils, monocytes and macrophages to inhibit recruitment, accelerate death, enhance efferocytosis and polarize macrophages towards a pro-repair phenotype. The effects of CGRP on neutrophils and macrophages are mediated via thrombospondin-1 release and its subsequent autocrine and/or paracrine effects. In mice without nociceptors and diabetic mice with peripheral neuropathies, delivery of an engineered version of CGRP accelerated wound healing and promoted muscle regeneration. Harnessing neuro-immune interactions has potential to treat non-healing tissues in which dysregulated neuro-immune interactions impair tissue healing.
Topics: Animals; Mice; Autocrine Communication; Calcitonin Gene-Related Peptide; Diabetes Mellitus, Experimental; Efferocytosis; Macrophages; Monocytes; Muscle, Skeletal; NAV1.8 Voltage-Gated Sodium Channel; Neutrophils; Nociceptors; Paracrine Communication; Peripheral Nervous System Diseases; Receptor Activity-Modifying Protein 1; Regeneration; Skin; Thrombospondin 1; Wound Healing; Humans; Male; Female
PubMed: 38538784
DOI: 10.1038/s41586-024-07237-y -
Cancer Immunology, Immunotherapy : CII Sep 2023The use of treatments, such as programmed death protein 1 (PD1) or cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) antibodies, that loosen the natural checks upon... (Review)
Review
The use of treatments, such as programmed death protein 1 (PD1) or cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) antibodies, that loosen the natural checks upon immune cell activity to enhance cancer killing have shifted clinical practice and outcomes for the better. Accordingly, the number of antibodies and engineered proteins that interact with the ligand-receptor components of immune checkpoints continue to increase along with their use. It is tempting to view these molecular pathways simply from an immune inhibitory perspective. But this should be resisted. Checkpoint molecules can have other cardinal functions relevant to the development and use of blocking moieties. Cell receptor CD47 is an example of this. CD47 is found on the surface of all human cells. Within the checkpoint paradigm, non-immune cell CD47 signals through immune cell surface signal regulatory protein alpha (SIRPα) to limit the activity of the latter, the so-called trans signal. Even so, CD47 interacts with other cell surface and soluble molecules to regulate biogas and redox signaling, mitochondria and metabolism, self-renewal factors and multipotency, and blood flow. Further, the pedigree of checkpoint CD47 is more intricate than supposed. High-affinity interaction with soluble thrombospondin-1 (TSP1) and low-affinity interaction with same-cell SIRPα, the so-called cis signal, and non-SIRPα ectodomains on the cell membrane suggests that multiple immune checkpoints converge at and through CD47. Appreciation of this may provide latitude for pathway-specific targeting and intelligent therapeutic effect.
Topics: Humans; CD47 Antigen; Antigens, Differentiation; Receptors, Immunologic; Neoplasms; Antibodies; Carrier Proteins; Phagocytosis
PubMed: 37217603
DOI: 10.1007/s00262-023-03465-9 -
Nature Communications Sep 2023Mesenchymal activation, characterized by dense stromal infiltration of immune and mesenchymal cells, fuels the aggressiveness of colorectal cancers (CRC), driving...
Mesenchymal activation, characterized by dense stromal infiltration of immune and mesenchymal cells, fuels the aggressiveness of colorectal cancers (CRC), driving progression and metastasis. Targetable molecules in the tumor microenvironment (TME) need to be identified to improve the outcome in CRC patients with this aggressive phenotype. This study reports a positive link between high thrombospondin-1 (THBS1) expression and mesenchymal characteristics, immunosuppression, and unfavorable CRC prognosis. Bone marrow-derived monocyte-like cells recruited by CXCL12 are the primary source of THBS1, which contributes to the development of metastasis by inducing cytotoxic T-cell exhaustion and impairing vascularization. Furthermore, in orthotopically generated CRC models in male mice, THBS1 loss in the TME renders tumors partially sensitive to immune checkpoint inhibitors and anti-cancer drugs. Our study establishes THBS1 as a potential biomarker for identifying mesenchymal CRC and as a critical suppressor of antitumor immunity that contributes to the progression of this malignancy with a poor prognosis.
Topics: Humans; Male; Animals; Mice; Monocytes; Immunosuppression Therapy; Aggression; Immune Checkpoint Inhibitors; Colorectal Neoplasms; Tumor Microenvironment
PubMed: 37749092
DOI: 10.1038/s41467-023-41095-y -
Advanced Science (Weinheim,... Jul 2023Subarachnoid hemorrhage (SAH) is a devastating subtype of stroke with high mortality and disability rate. Meningeal lymphatic vessels (mLVs) are a newly discovered...
Subarachnoid hemorrhage (SAH) is a devastating subtype of stroke with high mortality and disability rate. Meningeal lymphatic vessels (mLVs) are a newly discovered intracranial fluid transport system and are proven to drain extravasated erythrocytes from cerebrospinal fluid into deep cervical lymph nodes after SAH. However, many studies have reported that the structure and function of mLVs are injured in several central nervous system diseases. Whether SAH can cause mLVs injury and the underlying mechanism remain unclear. Herein, single-cell RNA sequencing and spatial transcriptomics are applied, along with in vivo/vitro experiments, to investigate the alteration of the cellular, molecular, and spatial pattern of mLVs after SAH. First, it is demonstrated that SAH induces mLVs impairment. Then, through bioinformatic analysis of sequencing data, it is discovered that thrombospondin 1 (THBS1) and S100A6 are strongly associated with SAH outcome. Furthermore, the THBS1-CD47 ligand-receptor pair is found to function as a key role in meningeal lymphatic endothelial cell apoptosis via regulating STAT3/Bcl-2 signaling. The results illustrate a landscape of injured mLVs after SAH for the first time and provide a potential therapeutic strategy for SAH based on mLVs protection by disrupting THBS1 and CD47 interaction.
Topics: Humans; Subarachnoid Hemorrhage; CD47 Antigen; Transcriptome; Lymphatic Vessels; Sequence Analysis, RNA
PubMed: 37211686
DOI: 10.1002/advs.202301428 -
Cancer Research Sep 2023Identifying mechanisms underlying relapse is a major clinical issue for effective cancer treatment. The emerging understanding of the importance of metastasis in...
UNLABELLED
Identifying mechanisms underlying relapse is a major clinical issue for effective cancer treatment. The emerging understanding of the importance of metastasis in hematologic malignancies suggests that it could also play a role in drug resistance and relapse in acute myeloid leukemia (AML). In a cohort of 1,273 AML patients, we uncovered that the multifunctional scavenger receptor CD36 was positively associated with extramedullary dissemination of leukemic blasts, increased risk of relapse after intensive chemotherapy, and reduced event-free and overall survival. CD36 was dispensable for lipid uptake but fostered blast migration through its binding with thrombospondin-1. CD36-expressing blasts, which were largely enriched after chemotherapy, exhibited a senescent-like phenotype while maintaining their migratory ability. In xenograft mouse models, CD36 inhibition reduced metastasis of blasts and prolonged survival of chemotherapy-treated mice. These results pave the way for the development of CD36 as an independent marker of poor prognosis in AML patients and a promising actionable target to improve the outcome of patients.
SIGNIFICANCE
CD36 promotes blast migration and extramedullary disease in acute myeloid leukemia and represents a critical target that can be exploited for clinical prognosis and patient treatment.
Topics: Humans; Animals; Mice; Leukemia, Myeloid, Acute; Treatment Outcome; Prognosis; Recurrence; Blast Crisis; Chronic Disease
PubMed: 37327406
DOI: 10.1158/0008-5472.CAN-22-3682 -
International Journal of Hematology Nov 2023Thrombotic thrombocytopenic purpura (TTP) can rapidly become a life-threatening condition, and the importance of its appropriate diagnosis and treatment cannot be...
Thrombotic thrombocytopenic purpura (TTP) can rapidly become a life-threatening condition, and the importance of its appropriate diagnosis and treatment cannot be overstated. Until recently, TTP has mainly been diagnosed by clinical findings such as thrombocytopenia and hemolytic anemia. In addition to these clinical findings, however, reduced activity of a disintegrin-like and metalloprotease with thrombospondin type 1 motif 13 (ADAMTS13) below 10% has become internationally accepted as a diagnostic criterion for TTP. TTP is classified as immune-mediated TTP (iTTP) if the patient is positive for anti-ADAMTS13 autoantibodies, and as congenital TTP (cTTP) if ADAMTS13 gene abnormalities are detected. Fresh frozen plasma (FFP) transfusion is performed in patients with cTTP to supplement ADAMTS13. Plasma exchange therapy using FFP is conducted in patients with iTTP to supplement ADAMTS13 and to remove both anti-ADAMTS13 autoantibodies and unusually large von Willebrand factor (VWF) multimers. To suppress autoantibody production, corticosteroid therapy is administered in conjunction with plasma exchange. The monoclonal anti-CD-20 antibody rituximab is effective in patients with iTTP. In addition, caplacizumab, an anti-VWF A1 domain nanobody, has a novel mechanism of action, involving direct inhibition of platelet glycoprotein Ib-VWF binding. The recommended first-line treatments of iTTP in Japan are plasma exchange and corticosteroids, as well as caplacizumab.
Topics: Humans; Purpura, Thrombotic Thrombocytopenic; Japan; von Willebrand Factor; Plasma Exchange; Autoantibodies; ADAMTS13 Protein
PubMed: 37689812
DOI: 10.1007/s12185-023-03657-0 -
Frontiers in Cardiovascular Medicine 2023Adipokines are biologically active factors secreted by adipose tissue that act on local and distant tissues through autocrine, paracrine, and endocrine mechanisms.... (Review)
Review
Adipokines are biologically active factors secreted by adipose tissue that act on local and distant tissues through autocrine, paracrine, and endocrine mechanisms. However, adipokines are believed to be involved in an increased risk of atherosclerosis. Classical adipokines include leptin, adiponectin, and ceramide, while newly identified adipokines include visceral adipose tissue-derived serpin, omentin, and asprosin. New evidence suggests that adipokines can play an essential role in atherosclerosis progression and regression. Here, we summarize the complex roles of various adipokines in atherosclerosis lesions. Representative protective adipokines include adiponectin and neuregulin 4; deteriorating adipokines include leptin, resistin, thrombospondin-1, and C1q/tumor necrosis factor-related protein 5; and adipokines with dual protective and deteriorating effects include C1q/tumor necrosis factor-related protein 1 and C1q/tumor necrosis factor-related protein 3; and adipose tissue-derived bioactive materials include sphingosine-1-phosphate, ceramide, and adipose tissue-derived exosomes. However, the role of a newly discovered adipokine, asprosin, in atherosclerosis remains unclear. This article reviews progress in the research on the effects of adipokines in atherosclerosis and how they may be regulated to halt its progression.
PubMed: 37645520
DOI: 10.3389/fcvm.2023.1235953 -
Arteriosclerosis, Thrombosis, and... Jul 2023TSP1 (thrombospondin-1)-a well-known angiogenesis inhibitor-mediates differential effects via interacting with cell surface receptors including CD36 (cluster of...
BACKGROUND
TSP1 (thrombospondin-1)-a well-known angiogenesis inhibitor-mediates differential effects via interacting with cell surface receptors including CD36 (cluster of differentiation) and CD47. However, the role of TSP1 in regulating lymphangiogenesis is not clear. Our previous study suggested the importance of cell-specific CD47 blockade in limiting atherosclerosis. Further, our experiments revealed CD47 as a dominant TSP1 receptor in lymphatic endothelial cells (LECs). As the lymphatic vasculature is functionally linked to atherosclerosis, we aimed to investigate the effects of LEC TSP1-CD47 signaling inhibition on lymphangiogenesis and atherosclerosis.
METHODS
Murine atherosclerotic and nonatherosclerotic arteries were utilized to investigate TSP1 expression using Western blotting and immunostaining. LEC-specific knockout mice were used to determine the in vivo role of LEC in lymphangiogenesis and atherosclerosis. Various in vitro cell-based assays, in vivo Matrigel plug implantation, molecular biological techniques, and immunohistological approaches were used to evaluate the underlying signaling mechanisms.
RESULTS
Elevated TSP1 expression was observed in mouse atherosclerotic aortic tissue compared with nonatherosclerotic control tissue. TSP1 at pathological concentrations suppressed both in vitro and in vivo lymphangiogenesis. Mechanistically, TSP1 inhibited VEGF (vascular endothelial growth factor)-C-induced AKT and eNOS activation in LEC and attenuated NO (nitric oxide) production. Further, silencing in LEC prevented the effects of TSP1 on lymphangiogenic AKT-eNOS signaling and lymphangiogenesis. Atheroprone AAV (adeno-associated virus) 8--injected LEC-specific knockout mice () had reduced atherosclerosis in both aorta and aortic root compared with control mice (). However, no differences in metabolic parameters including body weight, plasma total cholesterol levels, and fasting blood glucose were observed. Additional immunostaining experiments performed on aortic root cross-sections indicated higher lymphatic vessel density in mice in comparison to controls.
CONCLUSIONS
These findings demonstrate that TSP1 inhibits lymphangiogenesis via activation of CD47 in LEC, and loss of LEC attenuates atherosclerotic lesion formation. Collectively, these results identify LEC CD47 as a potential therapeutic target in atherosclerosis.
Topics: Animals; Mice; Atherosclerosis; CD47 Antigen; Endothelial Cells; Lymphangiogenesis; Mice, Knockout; Proprotein Convertase 9; Proto-Oncogene Proteins c-akt; Thrombospondin 1; Vascular Endothelial Growth Factor A
PubMed: 37259865
DOI: 10.1161/ATVBAHA.122.318904 -
Seminars in Cell & Developmental Biology Mar 2024Thrombospondin-1 is a secreted matricellular glycoprotein that modulates cell behavior by interacting with components of the extracellular matrix and with several cell... (Review)
Review
Thrombospondin-1 is a secreted matricellular glycoprotein that modulates cell behavior by interacting with components of the extracellular matrix and with several cell surface receptors. Its presence in the extracellular matrix is induced by injuries that cause thrombospondin-1 release from platelets and conditions including hyperglycemia, ischemia, and aging that stimulate its expression by many cell types. Conversely, rapid receptor-mediated clearance of thrombospondin-1 from the extracellular space limits its sustained presence in the extracellular space and maintains sub-nanomolar physiological concentrations in blood plasma. Roles for thrombospondin-1 signaling, mediated by specific cellular receptors or by activation of latent TGFβ, have been defined in T and B lymphocytes, natural killer cells, macrophages, neutrophils, and dendritic cells. In addition to regulating physiological nitric oxide signaling and responses of cells to stress, studies in mice lacking thrombospondin-1 or its receptors have revealed important roles for thrombospondin-1 in regulating immune responses in infectious and autoimmune diseases and antitumor immunity.
Topics: Animals; Mice; CD47 Antigen; Signal Transduction; Extracellular Matrix; Thrombospondins
PubMed: 37258315
DOI: 10.1016/j.semcdb.2023.05.008 -
Journal of Cell Communication and... Sep 2023Matricellular proteins comprise several families of secreted proteins that function in higher animals at the interface between cells and their surrounding extracellular... (Review)
Review
Matricellular proteins comprise several families of secreted proteins that function in higher animals at the interface between cells and their surrounding extracellular matrix. Targeted gene disruptions that result in loss of viability in mice have revealed critical roles for several matricellular proteins in murine embryonic development, including two members of the cellular communication network (CCN) gene family. In contrast, mice lacking single or multiple members of the thrombospondin (THBS) gene family remain viable and fertile. The frequency of loss of function mutants, identified using human deep exome sequencing data, provided evidence that some of the essential genes in mice, including Ccn1, are also essential genes in humans. However, a deficit in loss of function mutants in humans indicated that THBS1 is also highly loss-intolerant. In addition to roles in embryonic development or adult reproduction, genes may be loss-intolerant in humans because their function is needed to survive environmental stresses that are encountered between birth and reproduction. Laboratory mice live in a protected environment that lacks the exposures to pathogens and injury that humans routinely face. However, subjecting Thbs1 mice to defined stresses has provided valuable insights into functions of thrombospondin-1 that could account for the loss-intolerance of THBS1 in humans. Stress response models using transgenic mice have identified protective functions of thrombospondin-1 in the cardiovascular system (red) and immune defenses (blue) that could account for its intolerance to loss of function mutants in humans.
PubMed: 36689135
DOI: 10.1007/s12079-023-00722-5