{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"bioRxiv"}],"indexed":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T14:16:16Z","timestamp":1784297776595,"version":"3.55.0"},"posted":{"date-parts":[[2025,6,1]]},"group-title":"Immunology","reference-count":41,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2025,6,1]],"date-time":"2025-06-01T00:00:00Z","timestamp":1748736000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2025,6,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:sec>\n                  <jats:title>Introduction<\/jats:title>\n                  <jats:p>Macrophages (M\u03a6) modulate both myocardial inflammatory and reparative phases following ischemia-reperfusion (I\/R) injury. The mechanistic target of rapamycin (mTOR) is thought to play an important role in M\u03a6 phenotype and functionality, but studies report conflicting net influences suggesting dependence on disease context and downstream signaling. Here, we tested the impact of M\u03a6 with constitutive mTORC1 activation induced by targeted deletion of tuberous sclerosis complex 2 (TSC2) on cardiac responses to I\/R injury.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Methods\/Results<\/jats:title>\n                  <jats:p>\n                    Myeloid TSC2 depleted (M\u03a6\n                    <jats:sup>TSC2-\/-<\/jats:sup>\n                    ) mice were generated by crossing Lys2\n                    <jats:sup>Cre<\/jats:sup>\n                    x TSC2\n                    <jats:sup>flx\/flx<\/jats:sup>\n                    . Bone-marrow derived M\u03a6\n                    <jats:sup>TSC2-\/-<\/jats:sup>\n                    vs control M\u03a6 had basal increased mTORC1 and reduced mTORC2 activity. M\u03a6\n                    <jats:sup>TSC2-\/-<\/jats:sup>\n                    were differentially responsive to stimulation by lipopoly- saccharide\/IFN-\u03b3 or IL-4\n                    <jats:italic>in vitro<\/jats:italic>\n                    , and all disparities were prevented by rapamycin confirming the model. In vivo, M\u03a6\n                    <jats:sup>TSC2-\/-<\/jats:sup>\n                    mice were strongly protected against I\/R injury, with minimal change in ejection fraction, less LV dilation, hypertrophy, lung edema, or activation of stress\/pro fibrotic genes. Mice pre-treated with anti-LY6G Ab to deplete neutrophils were still similarly protected, suggesting that the impact was primarily related to M\u03a6. M\u03a6\n                    <jats:sup>TSC2-\/-<\/jats:sup>\n                    mice had less myocardial pro- inflammatory macrophages (CCR2\n                    <jats:sup>+<\/jats:sup>\n                    MHC-II\n                    <jats:sup>hi<\/jats:sup>\n                    ), LY6C\n                    <jats:sup>+<\/jats:sup>\n                    monocytes, neutrophils, and CD8\n                    <jats:sup>+<\/jats:sup>\n                    T cells 5 days post-I\/R, and fewer CCR2\n                    <jats:sup>+<\/jats:sup>\n                    but more CCR2\n                    <jats:sup>-<\/jats:sup>\n                    M\u03a6 2 weeks post I\/R. Both M\u03a6\n                    <jats:sup>TSC2-\/-<\/jats:sup>\n                    in vitro and in vivo post I\/R phenotypes were converted to WT by rapamycin, supporting mTORC1 dependence. Lastly, synthesis of glycoprotein nonmetastatic melanoma protein B (GPNMB), a principally M\u03a6 anti-inflammatory secreted protein protective against myocardial infarction was enhanced in M\u03a6\n                    <jats:sup>TSC2-\/-<\/jats:sup>\n                    macrophages and hearts following I\/R in an mTORC1 dependent manner.\n                    <jats:bold>Conclusion:<\/jats:bold>\n                    Constitutive macrophage-specific mTORC1 activation via TSC2 deletion reduces pro-inflammatory cell infiltration, increases GPNMB protein expression and preserves heart function following I\/R injury. Rapamycin eliminates these effects. These results identify a cardioprotective mTORC1-GPNMB signaling nexus in M\u03a6 in vivo.\n                  <\/jats:p>\n                <\/jats:sec>","DOI":"10.1101\/2025.05.29.656917","type":"posted-content","created":{"date-parts":[[2025,6,2]],"date-time":"2025-06-02T00:20:10Z","timestamp":1748823610000},"source":"Crossref","is-referenced-by-count":1,"title":["Macrophages Lacking TSC2 have mTORC1-dependent GPNMB Augmentation Ameliorating Cardiac Ischemia-Reperfusion Injury"],"prefix":"10.64898","author":[{"given":"Mohammad","family":"Keykhaei","sequence":"first","affiliation":[{"name":"Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3021-3894","authenticated-orcid":false,"given":"Navid","family":"Koleini","sequence":"additional","affiliation":[{"name":"Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mariam","family":"Meddeb","sequence":"additional","affiliation":[{"name":"Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Masih","family":"Tajdini","sequence":"additional","affiliation":[{"name":"Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Malihe","family":"Rezaee","sequence":"additional","affiliation":[{"name":"Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiao","family":"Huang","sequence":"additional","affiliation":[{"name":"Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tegbir","family":"Panesar","sequence":"additional","affiliation":[{"name":"Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark","family":"Ranek","sequence":"additional","affiliation":[{"name":"Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2704-978X","authenticated-orcid":false,"given":"Luigi","family":"Adamo","sequence":"additional","affiliation":[{"name":"Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1596-2299","authenticated-orcid":false,"given":"David A.","family":"Kass","sequence":"additional","affiliation":[{"name":"Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"54368","reference":[{"key":"2026041200295921000_2025.05.29.656917v1.1","doi-asserted-by":"crossref","unstructured":"Safiri S , Karamzad N , Singh K , Carson-Chahhoud K , Adams C , Nejadghaderi SA , Almasi-Hashiani A , Sullman MJM , Mansournia MA , Bragazzi NL , Kaufman JS , Collins GS and Kolahi AA . Burden of ischemic heart disease and its attributable risk factors in 204 countries and territories, 1990-2019. Eur J Prev Cardiol. 2022;29:420-431.","DOI":"10.1093\/eurjpc\/zwab213"},{"key":"2026041200295921000_2025.05.29.656917v1.2","doi-asserted-by":"publisher","DOI":"10.1172\/JCI62874"},{"key":"2026041200295921000_2025.05.29.656917v1.3","doi-asserted-by":"crossref","unstructured":"Jiang Y , Yu W , Hu T , Peng H , Hu F , Yuan Y , Liu X , Lai S , Zhou J and Dong X . Unveiling macrophage diversity in myocardial ischemia-reperfusion injury: identification of a distinct lipid- associated macrophage subset. Front Immunol. 2024;15:1335333.","DOI":"10.3389\/fimmu.2024.1335333"},{"key":"2026041200295921000_2025.05.29.656917v1.4","doi-asserted-by":"crossref","first-page":"959","DOI":"10.1038\/s41401-023-01222-3","article-title":"Macrophages promote the transition from myocardial ischemia reperfusion injury to cardiac fibrosis in mice through GMCSF\/CCL2\/CCR2 and phenotype switching","volume":"45","year":"2024","journal-title":"Acta Pharmacologica Sinica"},{"key":"2026041200295921000_2025.05.29.656917v1.5","doi-asserted-by":"publisher","DOI":"10.1016\/j.molimm.2024.02.007"},{"key":"2026041200295921000_2025.05.29.656917v1.6","doi-asserted-by":"publisher","DOI":"10.1161\/CIRCRESAHA.124.323817"},{"key":"2026041200295921000_2025.05.29.656917v1.7","doi-asserted-by":"publisher","DOI":"10.1038\/ncomms3834"},{"key":"2026041200295921000_2025.05.29.656917v1.8","doi-asserted-by":"publisher","DOI":"10.1016\/j.yjmcc.2023.10.011"},{"key":"2026041200295921000_2025.05.29.656917v1.9","doi-asserted-by":"publisher","DOI":"10.1038\/nri3901"},{"key":"2026041200295921000_2025.05.29.656917v1.10","doi-asserted-by":"crossref","unstructured":"Panwar V , Singh A , Bhatt M , Tonk RK , Azizov S , Raza AS , Sengupta S , Kumar D and Garg M . Multifaceted role of mTOR (mammalian target of rapamycin) signaling pathway in human health and disease. Signal Transduction and Targeted Therapy. 2023;8:375.","DOI":"10.1038\/s41392-023-01608-z"},{"key":"2026041200295921000_2025.05.29.656917v1.11","doi-asserted-by":"crossref","unstructured":"Henske EP , Jozwiak S , Kingswood JC , Sampson JR and Thiele EA . Tuberous sclerosis complex. Nat Rev Dis Primers. 2016;2:16035.","DOI":"10.1038\/nrdp.2016.35"},{"key":"2026041200295921000_2025.05.29.656917v1.12","doi-asserted-by":"publisher","DOI":"10.1016\/j.immuni.2008.08.012"},{"key":"2026041200295921000_2025.05.29.656917v1.13","doi-asserted-by":"publisher","DOI":"10.1038\/ng1494"},{"key":"2026041200295921000_2025.05.29.656917v1.14","doi-asserted-by":"publisher","DOI":"10.1038\/ni.3655"},{"key":"2026041200295921000_2025.05.29.656917v1.15","doi-asserted-by":"publisher","DOI":"10.1161\/JAHA.123.030478"},{"key":"2026041200295921000_2025.05.29.656917v1.16","doi-asserted-by":"crossref","unstructured":"Liu X , Liu Y , Yang RX , Ding XJ and Liang ES . Loss of myeloid Tsc2 predisposes to angiotensin II-induced aortic aneurysm formation in mice. Cell Death Dis. 2022;13:972.","DOI":"10.1038\/s41419-022-05423-2"},{"key":"2026041200295921000_2025.05.29.656917v1.17","doi-asserted-by":"publisher","DOI":"10.1038\/s41467-022-34480-6"},{"key":"2026041200295921000_2025.05.29.656917v1.18","doi-asserted-by":"crossref","unstructured":"Hu X , Xu Y , Zhang Z , Tang Z , Zhang J , Luo Y , Deng W , Dong Z , Zhao Y and Na N . TSC1 Affects the Process of Renal Ischemia-Reperfusion Injury by Controlling Macrophage Polarization. Front Immunol. 2021;12:637335.","DOI":"10.3389\/fimmu.2021.637335"},{"key":"2026041200295921000_2025.05.29.656917v1.19","doi-asserted-by":"publisher","DOI":"10.1038\/ncomms5696"},{"key":"2026041200295921000_2025.05.29.656917v1.20","doi-asserted-by":"publisher","DOI":"10.1016\/j.bbrc.2018.03.027"},{"key":"2026041200295921000_2025.05.29.656917v1.21","doi-asserted-by":"publisher","DOI":"10.1159\/000430306"},{"key":"2026041200295921000_2025.05.29.656917v1.22","doi-asserted-by":"publisher","DOI":"10.4049\/jimmunol.2100230"},{"key":"2026041200295921000_2025.05.29.656917v1.23","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2010-09-310888"},{"key":"2026041200295921000_2025.05.29.656917v1.24","doi-asserted-by":"publisher","DOI":"10.1038\/s44161-024-00555-4"},{"key":"2026041200295921000_2025.05.29.656917v1.25","doi-asserted-by":"crossref","unstructured":"Saade M , Araujo de Souza G , Scavone C and Kinoshita PF . The Role of GPNMB in Inflammation. Front Immunol. 2021;12:674739.","DOI":"10.3389\/fimmu.2021.674739"},{"key":"2026041200295921000_2025.05.29.656917v1.26","doi-asserted-by":"publisher","DOI":"10.1530\/ERC-15-0505"},{"key":"2026041200295921000_2025.05.29.656917v1.27","doi-asserted-by":"crossref","unstructured":"Ono Y , Tsuruma K , Takata M , Shimazawa M and Hara H . Glycoprotein nonmetastatic melanoma protein B extracellular fragment shows neuroprotective effects and activates the PI3K\/Akt and MEK\/ERK pathways via the Na+\/K+-ATPase. Sci Rep. 2016;6:23241.","DOI":"10.1038\/srep23241"},{"key":"2026041200295921000_2025.05.29.656917v1.28","doi-asserted-by":"publisher","DOI":"10.1002\/path.5875"},{"key":"2026041200295921000_2025.05.29.656917v1.29","doi-asserted-by":"crossref","unstructured":"Patel CH , Dong Y , Koleini N , Wang X , Dunkerly-Eyring BL , Wen J , Ranek MJ , Bartle LM , Henderson DB , Sagert J , Kass DA and Powell JD . TSC2 S1365A mutation potently regulates CD8+ T cell function and differentiation and improves adoptive cellular cancer therapy. JCI Insight. 2023;8.","DOI":"10.1172\/jci.insight.167829"},{"key":"2026041200295921000_2025.05.29.656917v1.30","doi-asserted-by":"publisher","DOI":"10.1161\/CIRCRESAHA.110.223925"},{"key":"2026041200295921000_2025.05.29.656917v1.31","doi-asserted-by":"publisher","DOI":"10.1161\/CIRCRESAHA.118.314028"},{"key":"2026041200295921000_2025.05.29.656917v1.32","doi-asserted-by":"crossref","unstructured":"Gibbons E , Taya M , Wu H , Lopa SH , Moss J , Henske EP , McCormack FX and Hammes SR . Glycoprotein non-metastatic melanoma protein B promotes tumor growth and is a biomarker for lymphangioleiomyomatosis. Endocr Relat Cancer. 2024;31.","DOI":"10.1530\/ERC-23-0312"},{"key":"2026041200295921000_2025.05.29.656917v1.33","doi-asserted-by":"publisher","DOI":"10.2353\/ajpath.2010.090950"},{"key":"2026041200295921000_2025.05.29.656917v1.34","doi-asserted-by":"crossref","unstructured":"Zhu Z , Liu Y , Li X , Zhang L , Liu H , Cui Y , Wang Y and Zhao D . GPNMB mitigates Alzheimer\u2019s disease and enhances autophagy via suppressing the mTOR signal. Neurosci Lett. 2022;767:136300.","DOI":"10.1016\/j.neulet.2021.136300"},{"key":"2026041200295921000_2025.05.29.656917v1.35","doi-asserted-by":"publisher","DOI":"10.1161\/CIRCRESAHA.121.320449"},{"key":"2026041200295921000_2025.05.29.656917v1.36","doi-asserted-by":"crossref","unstructured":"Chen B , Brickshawana A and Frangogiannis NG . The Functional Heterogeneity of Resident Cardiac Macrophages in Myocardial Injury(CCR2(+) Cells Promote Inflammation, Whereas CCR2(-) Cells Protect). Circ Res. 2019;124:183-185.","DOI":"10.1161\/CIRCRESAHA.118.314357"},{"key":"2026041200295921000_2025.05.29.656917v1.37","doi-asserted-by":"crossref","unstructured":"Chen G , Jiang H , Yao Y , Tao Z , Chen W , Huang F and Chen X . Macrophage, a potential targeted therapeutic immune cell for cardiomyopathy. Front Cell Dev Biol. 2022;10:908790.","DOI":"10.3389\/fcell.2022.908790"},{"key":"2026041200295921000_2025.05.29.656917v1.38","doi-asserted-by":"publisher","DOI":"10.1016\/S0002-9440(10)63309-3"},{"key":"2026041200295921000_2025.05.29.656917v1.39","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacbts.2022.06.001"},{"key":"2026041200295921000_2025.05.29.656917v1.40","doi-asserted-by":"crossref","unstructured":"Xu X , Xie K , Li B , Xu L , Huang L , Feng Y , Pi C , Zhang J , Huang T , Jiang M , Gu H and Fang J . Adaptive resistance in tumors to anti-PD-1 therapy through re-immunosuppression by upregulation of GPNMB expression. Int Immunopharmacol. 2021;101:108199.","DOI":"10.1016\/j.intimp.2021.108199"},{"key":"2026041200295921000_2025.05.29.656917v1.41","doi-asserted-by":"crossref","unstructured":"Yu B , Sondag GR , Malcuit C , Kim MH and Safadi FF . Macrophage-Associated Osteoactivin\/GPNMB Mediates Mesenchymal Stem Cell Survival, Proliferation, and Migration Via a CD44-Dependent Mechanism. J Cell Biochem. 2016;117:1511-21.","DOI":"10.1002\/jcb.25394"}],"container-title":[],"original-title":[],"link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1101\/2025.05.29.656917","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,12]],"date-time":"2026-04-12T07:30:09Z","timestamp":1775979009000},"score":1,"resource":{"primary":{"URL":"http:\/\/biorxiv.org\/lookup\/doi\/10.1101\/2025.05.29.656917"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,6,1]]},"references-count":41,"URL":"https:\/\/doi.org\/10.1101\/2025.05.29.656917","relation":{},"subject":[],"published":{"date-parts":[[2025,6,1]]},"subtype":"preprint"}}