Identification of new ocellatin antimicrobial peptides by cdna precursor cloning in the frame of this family of intriguing peptides

Ocellatins are a family of antimicrobial peptides found exclusively in the Leptodactylus genus. To date, 10 species have been studied and more than 23 peptides described. Here we report the sequences of five new peptides from the skin of the frog Leptodactylus latrans (Anura: Leptodactylidae) determined by cDNA cloning of the complete prepro-peptide structures. The mature peptides were characterized with in silico tools and compared with those previously described. With 21 amino acid residues, this new set of peptides not previously described in the Leptodactylus genus share between 100 and 76.2% similarity to ocellatin antimicrobial peptides. These novel peptides are cationic and their three-dimensional (3D) structure holds the highly conserved residues G1, D4, K7, and K11 and a high theoretical amphipathic α-helix content. Furthermore, in silico analyses of these new peptides predicted antimicrobial activity. This study is framed in the context of previous work published about ocellatins, and therefore, provides a review of this intriguing family of peptides.Fil: Marani, Mariela Mirta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; ArgentinaFil: Aguilar, Silvana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; ArgentinaFil: Cuzziol Boccioni, Ana Paula. Universidad Nacional del Litoral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; ArgentinaFil: Cancelarich, Natalia Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; ArgentinaFil: Basso, Nestor Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Diversidad y Evolución Austral; ArgentinaFil: Albericio Palomera, Fernando. Consejo Superior de Investigaciones Científicas. Instituto de Química Avanzada de Catalunya; España. Universidad de Barcelona; España. University of KwaZulu-Natal; Sudáfric

Comparative proteomic analysis of nuclear and cytoplasmic compartments in human cardiac progenitor cells.

Clinical trials evaluating cardiac progenitor cells (CPC) demonstrated feasibility and safety, but no clear functional benefits. Therefore a deeper understanding of CPC biology is warranted to inform strategies capable to enhance their therapeutic potential. Here we have defined, using a label-free proteomic approach, the differential cytoplasmic and nuclear compartments of human CPC (hCPC). Global analysis of cytoplasmic repertoire in hCPC suggested an important hypoxia response capacity and active collagen metabolism. In addition, comparative analysis of the nuclear protein compartment identified a significant regulation of a small number of proteins in hCPC versus human mesenchymal stem cells (hMSC). Two proteins significantly upregulated in the hCPC nuclear compartment, IL1A and IMP3, showed also a parallel increase in mRNA expression in hCPC versus hMSC, and were studied further. IL1A, subjected to an important post-transcriptional regulation, was demonstrated to act as a dual-function cytokine with a plausible role in apoptosis regulation. The knockdown of the mRNA binding protein (IMP3) did not negatively impact hCPC viability, but reduced their proliferation and migration capacity. Analysis of a panel of putative candidate genes identified HMGA2 and PTPRF as IMP3 targets in hCPC. Therefore, they are potentially involved in hCPC proliferation/migration regulation.THis study was initiated by European Commission funding (HEALTH-2009_242038) and by grants to AB from the Spanish Ministry of Science and Innovation RTI2018-097604-B-I00 (AEI/FEDER, UE) and SAF2015- 70882-R. Te Research Program of the Comunidad Autónoma de Madrid (S2017/BMD-3692) and the Instituto de Salud Carlos III (RETICS-RTI2018-097604-B-I00) to AB also funded parts of the work. We also wish to thank to K McCreath for editorial work.S

Enhanced cross-recognition of SARS-CoV-2 Omicron variant by peptide vaccine-induced antibodies

Current vaccines against SARS-CoV-2, based on the original Wuhan sequence, induce antibodies with different degrees of cross-recognition of new viral variants of concern. Despite potent responses generated in vaccinated and infected individuals, the Omicron (B.1.1.529) variant causes breakthrough infections, facilitating viral transmission. We previously reported a vaccine based on a cyclic peptide containing the 446-488 S1 sequence (446-488cc) of the SARS-CoV-2 spike (S) protein from Wuhan isolate. To provide the best immunity against Omicron, here we compared Omicron-specific immunity induced by a Wuhanbased 446-488cc peptide, by a Wuhan-based recombinant receptor-binding domain (RBD) vaccine and by a new 446-488cc peptide vaccine based on the Omicron sequence. Antibodies induced by Wuhan peptide 446-488cc in three murine strains not only recognized the Wuhan and Omicron 446-488 peptides similarly, but also Wuhan and Omicron RBD protein variants. By contrast, antibodies induced by the Wuhan recombinant RBD vaccine showed a much poorer cross-reactivity for the Omicron RBD despite similar recognition of Wuhan and Omicron peptide variants. Finally, although the Omicron-based 446-488cc peptide vaccine was poorly immunogenic in mice due to the loss of T cell epitopes, co-immunization with Omicron peptide 446-488cc and exogenous T cell epitopes induced strong cross-reactive antibodies that neutralized Omicron SARS-CoV-2 virus. Since mutations occurring within this sequence do not alter T cell epitopes in humans, these results indicate the robust immunogenicity of 446-488cc-based peptide vaccines that induce antibodies with a high crossrecognition capacity against Omicron, and suggest that this sequence could be included in future vaccines targeting the Omicron variant.This work was supported by Instituto de Salud Carlos III, Fondo Europeo de Desarrollo Regional “Una manera de hacer Europa” under grant PI20/00260, Gobierno de Navarra under grant 0011- 3597-2020-000024 to PS and by Paula & Rodger Riney Foundation to JJL. This research was also supported by Spanish Research Council (CSIC) grants 202120E079 (to JG-A) and 2020E84 (to ME), Spanish Ministry of Science and Innovation (MCIN)/Spanish Research Agency (AEI)/10.13039/501100011033 grant (PID2020-114481RBI00; to JG-A and ME), and Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC) co-financed with FEDER funds (to JG-A). This research work was also funded by the European Commission-NextGenerationEU, through CSIC’s Global Health Platform (PTI Salud Global) (to JG-A and ME). JG-A and ME also acknowledge financial support from the Spanish State Research Agency, AEI/10.13039/501100011033, through the “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV-2013-0347, SEV- 2017-0712).Peer reviewe

Cardiac Progenitor Cell Exosomal miR-935 Protects against Oxidative Stress

This work has been funded by grants from the Spanish Ministry of Science and Innovation RTI2018-097604-B-I00 (funded by MCIN/AEI/10.13039/501100011033/ and FEDER) and PID2021- 128698OB-I00 (MCIN/AEI/10.13039/501100011033); by the Regional Government of Madrid (S2017/ BMD-3692, Avancell), and by the Instituto de Salud Carlos III (RD16/0011/0037) to AB and by the Instituto Salud Carlos III (ISCIII), co-funded by European Regional Development Fund-FEDER (PI19/00501 and PI22/00029), and Gobierno de Navarra (s/n) to BP. JV has been funded by MCIN grant PID2021-122348NB-I00 and Regional Government of Madrid grant P2022/BMD-7333.S

Dendritic Cell‐Mediated Cross‐Priming by a Bispecific Neutralizing Antibody Boosts Cytotoxic T Cell Responses and Protects Mice against SARS‐CoV‐2

SARS-CoV-2 B.1.351 and B.1.167.2 viruses used in this study were obtained through the European Virus Archive Global (EVA-GLOBAL) project that has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 653316. SARS-CoV-2 B.1 (MAD6 isolate) was kindly provided by José M. Honrubia and Luis Enjuanes (CNB-CSIC, Madrid, Spain). The authors thank Centro de Investigación en Sanidad Animal (CISA)-Instituto Nacional de Investigaciones Agrarias (INIA-CSIC) (Valdeolmos, Madrid, Spain) for the BSL-3 facilities. Research in LAV laboratory was funded by the BBVA Foundation (Ayudas Fundación BBVA a Equipos de Investigación Científica SARS-CoV-2 y COVID19); the MCIN/AEI/10.13039/501100011033 (PID2020-117323RB-I00 and PDC2021-121711-I00), partially supported by the European Regional Development Fund (ERDF); the Carlos III Health Institute (ISCIII) (DTS20/00089), partially supported by the ERDF, the Spanish Association Against Cancer (AECC 19084); the CRIS Cancer Foundation (FCRISIFI-2018 and FCRIS-2021-0090), the Fundación Caixa-Health Research (HR21-00761 project IL7R_LungCan), and the Comunidad de Madrid (P2022/BMD-7225 NEXT_GEN_CART_MAD-CM). Work in the DS laboratory was funded by the CNIC; the European Union’s Horizon 2020 research and innovation program under grant agreement ERC-2016-Consolidator Grant 725091; MCIN/AEI/10.13039/501100011033 (PID2019-108157RB); Comunidad de Madrid (B2017/BMD-3733 Immunothercan-CM); Atresmedia (Constantes y Vitales prize); Fondo Solidario Juntos (Banco Santander); and “La Caixa” Foundation (LCF/PR/HR20/00075). The CNIC was supported by the ISCIII, the MCIN and the Pro CNIC Foundation and is a Severo Ochoa Center of Excellence (CEX2020- 001041-S funded by MCIN/AEI/10.13039/501100011033). Research in RD laboratory was supported by the ISCIII (PI2100989) and CIBERINFEC; the European Commission Horizon 2020 Framework Programme (grant numbers 731868 project VIRUSCAN FETPROACT-2016, and 101046084 project EPIC-CROWN-2); and the Fundación CaixaHealth Research (grant number HR18-00469 project StopEbola). Research in CNB-CSIC laboratory was funded by Fondo Supera COVID19 (Crue Universidades-Banco Santander) grant, CIBERINFEC, and Spanish Research Council (CSIC) grant 202120E079 (to J.G.-A.), CSIC grant 2020E84 (to M.E.), MCIN/AEI/10.13039/501100011033 (PID2020- 114481RB-I00 to J.G-A. and M.E.), and by the European CommissionNextGenerationEU, through CSIC’s Global Health Platform (PTI Salud Global) to J.G.-A. and M.E. Work in the CIB-CSIC laboratory was supported by MCIN/AEI/10.13039/501100011033 (PID2019-104544GB-I00 and 2023AEP105 to CA, and PID2020-113225GB-I00 to F.J.B.). Cryo-EM data were collected at the Maryland Center for Advanced Molecular Analyses which was supported by MPOWER (The University of Maryland Strategic Partnership). I.H.-M. receives the support of a fellowship from la Caixa Foundation (ID 100010434, fellowship code: LCF/BQ/IN17/11620074) and from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement no. 71367. L.R.-P. was supported by a predoctoral fellowship from the Immunology Chair, Universidad Francisco de Vitoria/Merck.S

Full protection from SARS-CoV-2 brain infection and damage in susceptible transgenic mice conferred by MVA-CoV2-S vaccine candidate

Vaccines against SARS-CoV-2 have been shown to be safe and effective but their protective efficacy against infection in the brain is yet unclear. Here, in the susceptible transgenic K18-hACE2 mouse model of severe coronavirus disease 2019 (COVID-19), we report a spatiotemporal description of SARS-CoV-2 infection and replication through the brain. SARS-CoV-2 brain replication occurs primarily in neurons, leading to neuronal loss, signs of glial activation and vascular damage in mice infected with SARS-CoV-2. One or two doses of a modified vaccinia virus Ankara (MVA) vector expressing the SARS-CoV-2 spike (S) protein (MVA-CoV2-S) conferred full protection against SARS-CoV-2 cerebral infection, preventing virus replication in all areas of the brain and its associated damage. This protection was maintained even after SARS-CoV-2 reinfection. These findings further support the use of MVA-CoV2-S as a promising vaccine candidate against SARS-CoV-2/COVID-19.We thank the CSIC and the Spanish Ministry of Science and Innovation for continuous support. This research was supported by the Spanish Ministry of Science and Innovation/Spanish Research Agency/10.13039/501100011033 grant nos. PID2019-105995RB-I00 (J.J.T.-A. and J.V.), PID2020-114481RB-I00 (J.G.-A. and M.E.), RTI2018-096629-B-I00 (A.P.) and PID2019-106410RB-I00 (J.L.-B.). Moreover, this research was also funded by Red TerCel ISCIII (no. RD16/0011/0025 to J.J.T.-A.), Consejería de Economía, Conocimiento, Empresas y Universidad US-1380891 (to J.J.T.-A. and J.V.), Consejería de Salud y Familias, Junta de Andalucía grant no. PECOVID-0078-2020 (to R.R.-L. and J.V.), Consejería de Educación y Deporte, Junta de Andalucía grant no. PY20_01312 (to A.P.), Fondo COVID-19 grant no. COV20/00151 (Spanish Health Ministry, Instituto de Salud Carlos III), Fondo Supera COVID-19 (Crue Universidades-Banco Santander) grant and CSIC grant no. 202120E079 (J.G.-A.), CSIC grant no. 2020E84, La CaixaImpulse grant no. CF01-00008 and Ferrovial and MAPFRE donations (to M.E.). Additionally, we received funding from the European Commission-NextGenerationEU, through the CSIC’s Global Health Platform (PTI Salud Global) (to J.G.-A. and M.E.) and the European Research Council (ERC Advanced grant no. PRJ201502629) (to J.L.-B.). J.G.-A. and M.E. also acknowledge financial support from the Spanish State Research Agency (no. AEI/10.13039/501100011033) through the ‘Severo Ochoa’ Programme for Centres of Excellence in R&D (nos. SEV-2013-0347 and SEV-2017-0712). The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript.Peer reviewe

Dendritic Cell-Mediated Cross-Priming by a Bispecific Neutralizing Antibody Boosts Cytotoxic T Cell Responses and Protects Mice against SARS-CoV-2

17 p.-4 fig.Administration of neutralizing antibodies (nAbs) has proved to be effective by providing immediate protection against SARS-CoV-2. However, dual strategies combining virus neutralization and immune response stimulation to enhance specific cytotoxic T cell responses, such as dendritic cell (DC) cross-priming, represent a promising field but have not yet been explored. Here, a broadly nAb, TNT, are first generated by grafting an anti-RBD biparatopic tandem nanobody onto a trimerbody scaffold. Cryo-EM data show that the TNT structure allows simultaneous binding to all six RBD epitopes, demonstrating a high-avidity neutralizing interaction. Then, by C-terminal fusion of an anti-DNGR-1 scFv to TNT, the bispecific trimerbody TNTDNGR-1 is generated to target neutralized virions to type 1 conventional DCs (cDC1s) and promote T cell cross-priming. Therapeutic administration of TNTDNGR-1, but not TNT, protects K18-hACE2 mice from a lethal SARS-CoV-2 infection, boosting virus-specific humoral responses and CD8+ T cell responses. These results further strengthen the central role of interactions with immune cells in the virus-neutralizing antibody activity and demonstrate the therapeutic potential of the Fc-free strategy that can be used advantageously to provide both immediate and long-term protection against SARS-CoV-2 and other viral infections.SARS-CoV-2 B.1.351 and B.1.167.2 viruses used in this study were obtained through the European Virus Archive Global (EVA-GLOBAL) project that has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 653316. SARS-CoV-2 B.1 (MAD6 isolate) was kindly provided by José M. Honrubia and Luis Enjuanes (CNB-CSIC, Madrid, Spain). The authors thank Centro de Investigación en Sanidad Animal (CISA)-Instituto Nacional de Investigaciones Agrarias (INIA-CSIC) (Valdeolmos, Madrid, Spain) for the BSL-3 facilities. Research in LA-V laboratory was funded by the BBVA Foundation (Ayudas Fundación BBVA a Equipos de Investigación Científica SARS-CoV-2 y COVID-19); the MCIN/AEI/10.13039/501100011033 (PID2020-117323RB-I00 and PDC2021-121711-I00), partially supported by the European Regional Development Fund (ERDF); the Carlos III Health Institute (ISCIII) (DTS20/00089), partially supported by the ERDF, the Spanish Association Against Cancer (AECC 19084); the CRIS Cancer Foundation (FCRIS-IFI-2018 and FCRIS-2021-0090), the Fundación Caixa-Health Research (HR21-00761 project IL7R_LungCan), and the Comunidad de Madrid (P2022/BMD-7225 NEXT_GEN_CART_MAD-CM). Work in the DS laboratory was funded by the CNIC; the European Union's Horizon 2020 research and innovation program under grant agreement ERC-2016-Consolidator Grant 725091; MCIN/AEI/10.13039/501100011033 (PID2019-108157RB); Comunidad de Madrid (B2017/BMD-3733 Immunothercan-CM); Atresmedia (Constantes y Vitales prize); Fondo Solidario Juntos (Banco Santander); and “La Caixa” Foundation (LCF/PR/HR20/00075). The CNIC was supported by the ISCIII, the MCIN and the Pro CNIC Foundation and is a Severo Ochoa Center of Excellence (CEX2020-001041-S funded by MCIN/AEI/10.13039/501100011033). Research in RD laboratory was supported by the ISCIII (PI2100989) and CIBERINFEC; the European Commission Horizon 2020 Framework Programme (grant numbers 731868 project VIRUSCAN FETPROACT-2016, and 101046084 project EPIC-CROWN-2); and the Fundación Caixa-Health Research (grant number HR18-00469 project StopEbola). Research in CNB-CSIC laboratory was funded by Fondo Supera COVID-19 (Crue Universidades-Banco Santander) grant, CIBERINFEC, and Spanish Research Council (CSIC) grant 202120E079 (to J.G.-A.), CSIC grant 2020E84 (to M.E.), MCIN/AEI/10.13039/501100011033 (PID2020-114481RB-I00 to J.G-A. and M.E.), and by the European Commission-NextGenerationEU, through CSIC's Global Health Platform (PTI Salud Global) to J.G.-A. and M.E. Work in the CIB-CSIC laboratory was supported by MCIN/AEI/10.13039/501100011033 (PID2019-104544GB-I00 and 2023AEP105 to CA, and PID2020-113225GB-I00 to F.J.B.). Cryo-EM data were collected at the Maryland Center for Advanced Molecular Analyses which was supported by MPOWER (The University of Maryland Strategic Partnership). I.H.-M. receives the support of a fellowship from la Caixa Foundation (ID 100010434, fellowship code: LCF/BQ/IN17/11620074) and from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement no. 71367. L.R.-P. was supported by a predoctoral fellowship from the Immunology Chair, Universidad Francisco de Vitoria/Merck.Peer reviewe

Análisis de los mecanismos centrales de regulación de los progenitores cardíacos Bmi1+ en ratón adulto

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de Lectura: 29-10-2021Esta tesis tiene embargado el acceso al texto completo hasta el 29-04-2023El corazón, a diferencia de la mayoría de órganos, no presenta una única población aceptada de células progenitoras adultas. Existe cierta controversia en el campo de las células progenitoras cardíacas, ya que varios autores han definido poblaciones con capacidades progenitoras que presentan características diferenciales. Nuestro grupo ha identificado una población de progenitores cardíacos adultos caracterizada por la expresión de niveles altos de Bmi1 (Bmi1-CPC). Esta población contribuye al recambio de los principales linajes celulares cardíacos en homeostasis, incrementando su aportación tras daño oxidativo. De hecho, la población Bmi1-CPC es esencial en la regeneración/reparación cardíaca tras infarto agudo de miocardio (IAM), desempeñando un papel fundamental en el proceso de revascularización. Se ha establecido que las células Bmi1-CPC residen preferentemente en regiones perivasculares, postulándose una relación de tipo nicho entre ellas y el endotelio cardíaco. Hasta la fecha, el estudio de la población Bmi1-CPC se ha centrado en el análisis de modelos in-vivo y cultivos primarios derivados de ellos. Sin embargo, el trabajo con estos modelos supone importantes limitaciones experimentales. Por esta razón, hemos desarrollado un modelo in-vitro inmortalizado derivado de las células Bmi1-CPC que nos permitiera profundizar en el estudio de esta población. Basamos la estrategia de inmortalización en la inducción de la expresión estable del gen del antígeno grande del poliomavirus S40 de simios (T-SV40). Este modelo, denominado Bmi1-CPC-YFPInm, mantiene las características definitorias de la población Bmi1-CPC y ha resultado una herramienta eficaz para el estudio de la relación entre estas células y el endotelio cardíaco. Utilizando este modelo in-vitro hemos podido definir que el secretoma de las Bmi1- CPC contiene factores que están directamente implicados en la regulación del endotelio. Mediante los factores secretados al espacio extracelular, las Bmi1-CPC inducen la migración de las células endoteliales en su proximidad. Este efecto se hace más intenso en condiciones de daño oxidativo y esta directamente regulado por la quimioquina CXCL12. Además, hemos demostrado que la población Bmi1-CPC tiene capacidad de inducir angiogénesis en condiciones de homeostasis, efecto que se reprime en condiciones de daño oxidativo. De forma adicional, hemos constatado que las células endoteliales influyen sobre las células Bmi1-CPC, generando sobre ellas un efecto protector frente a daño oxidativo. El contacto directo entre ambos tipos celulares reduce, a su vez, la proliferación y los niveles de especies reactivas de oxigeno (ROS) intracelulares en las células Bmi1-CPC. Postulamos que estos efectos podrían deberse a una activación de la ruta de Notch, implicada en la regulación de la proliferación celular, y a modificaciones del flujo autofágico y la actividad metabólica, mecanismos directamente implicados en la producción de ROS. Los datos obtenidos permiten proponer una relación de tipo cross-talk entre las Bmi1- CPC y la vasculatura cardíaca. Estos resultados definirían un mecanismo presente en progenitores residentes en otros órganos para una población de progenitores responsables del mantenimiento y regeneración el tejido cardíaco. Hasta la fecha no hay constancia de la descripción de un mecanismo similar dentro del corazón, lo que podría suponer una aportación relevante dentro del estudio de las poblaciones de progenitores cardíacos adulto

Exploring solid-phase approaches for the preparation of new β-lactams from amino acids

Two solid-phase approaches, involving the base-assisted intramolecularalkylation of N-chloroacetyl-Phe derivatives anchored to appropriatesolid supports, were investigated for the preparation of novel β-lactams. When a BAL-type strategy was used, the resin-bound azetidinones were easily formed, as established by MAS-NMR, but final compounds could not be removed from the resin, unless a suitable two linkers system was used. In the second approach, in which the Phe residue is anchored to a Wang-type resin through the carboxylate group, the corresponding 1,4,4-trisubstituted 2-azetidinone was obtained in moderate to good yield and high purity

Age-related oxidative stress confines damage-responsive Bmi1+ cells to perivascular regions in the murine adult heart

Adult progenitor cells reside in specialized microenvironments which maintain their undifferentiated cell state and trigger regenerative responses following injury. Although these environments are well described in several tissues, the cellular components that comprise the cardiac environment where progenitor cells are located remain unknown. Here we use Bmi1CreERT and Bmi1GFP mice as genetic tools to trace cardiac damage-responsive cells throughout the mouse lifespan. In adolescent mice, Bmi1+ damage-responsive cells are broadly distributed throughout the myocardium. In adult mice, however, Bmi1+ cells are confined predominately in perivascular areas with low levels of reactive oxygen species (ROS) and their number decline in an age-dependent manner. In vitro co-culture experiments with endothelial cells supported a regulatory role of the endothelium in damage-responsive cell behavior. Accordingly, in vivo genetic decrease of ROS levels in adult heart disengaged Bmi1+ cells from the cardiovascular network, recapitulating an adolescent-like Bmi1 expression profile. Thus, we identify cardiac perivascular regions as low-stress microenvironments that favor the maintenance of adult damage-responsive cells. Keywords: Bmi1, Damage-responsive cell, Vasculature, Oxidative damage, Reactive oxygen specie