Honors & Awards


  • Young Investigator Award, WORLDSymposium (2024)
  • Young Investigator Award, International Journal of Molecular Sciences (2023)
  • Honorable Mention in Biological Sciences, CAPES Thesis Award (2022)
  • Outstanding Ph.D. student, Postgraduate Program in Genetics and Molecular Biology (UFRGS) (2018)
  • Outstanding Undergraduate Research Project, XXIV Salão de Iniciação Científica UFRGS (2012)

Professional Education


  • PhD., Universidade Federal do Rio Grande do Sul, Genetics and Molecular Biology (2021)
  • M.Sc., Universidade Federal do Rio Grande do Sul, Genetics and Molecular Biology (2017)
  • B.Sc, Universidade Federal do Rio Grande do Sul, Biomedicine (2015)

Stanford Advisors


Lab Affiliations


All Publications


  • Improved engraftment and therapeutic efficacy by human genome-edited hematopoietic stem cells with Busulfan-based myeloablation. Molecular therapy. Methods & clinical development Poletto, E., Colella, P., Pimentel Vera, L. N., Khan, S., Tomatsu, S., Baldo, G., Gomez-Ospina, N. 2022; 25: 392-409

    Abstract

    Autologous hematopoietic stem cell transplantation using genome-edited cells can become a definitive therapy for hematological and non-hematological disorders with neurological involvement. Proof-of-concept studies using human genome-edited hematopoietic stem cells have been hindered by the low efficiency of engraftment of the edited cells in the bone marrow and their modest efficacy in the CNS. To address these challenges, we tested a myeloablative conditioning regimen based on Busulfan in an immunocompromised model of mucopolysaccharidosis type 1. Compared with sub-lethal irradiation, Busulfan conditioning enhanced the engraftment of edited CD34+ cells in the bone marrow, as well the long-term homing and survival of bone-marrow-derived cells in viscera, and in the CNS, resulting in higher transgene expression and biochemical correction in these organs. Edited cell selection using a clinically compatible marker resulted in a population withlow engraftment potential. We conclude that conditioning can impact the engraftment of edited hematopoietic stem cells.Furthermore, Busulfan-conditioned recipients have a higher expression of therapeutic proteins in target organs, particularly in the CNS, constituting a better conditioning approach for non-hematological diseases with neurological involvement.

    View details for DOI 10.1016/j.omtm.2022.04.009

    View details for PubMedID 35573043

  • Genome Editing for Mucopolysaccharidoses. International journal of molecular sciences Poletto, E. n., Baldo, G. n., Gomez-Ospina, N. n. 2020; 21 (2)

    Abstract

    Genome editing holds the promise of one-off and potentially curative therapies for many patients with genetic diseases. This is especially true for patients affected by mucopolysaccharidoses as the disease pathophysiology is amenable to correction using multiple approaches. Ex vivo and in vivo genome editing platforms have been tested primarily on MSPI and MPSII, with in vivo approaches having reached clinical testing in both diseases. Though we still await proof of efficacy in humans, the therapeutic tools established for these two diseases should pave the way for other mucopolysaccharidoses. Herein, we review the current preclinical and clinical development studies, using genome editing as a therapeutic approach for these diseases. The development of new genome editing platforms and the variety of genetic modifications possible with each tool provide potential applications of genome editing for mucopolysaccharidoses, which vastly exceed the potential of current approaches. We expect that in a not-so-distant future, more genome editing-based strategies will be established, and individual diseases will be treated through multiple approaches.

    View details for DOI 10.3390/ijms21020500

    View details for PubMedID 31941077

  • Engineering monocyte/macrophage−specific glucocerebrosidase expression in human hematopoietic stem cells using genome editing Nature Communications Scharenberg, S. G., Poletto, E., Lucot, K. L., Colella, P., Sheikali, A., Montine, T. J., Porteus, M. H., Gomez-Ospina, N. 2020; 11: 1-14
  • Basic and translational research in rare diseases in low- and middle-income countries: challenges and solutions. Journal of community genetics Rodrigues, G., Poletto, E., E Vairo, F. P., Baldo, G. 2024

    Abstract

    In this document, we discuss the main difficulties faced by investigators in low- and middle-income countries (LMICs) and propose potential solutions. Challenges include the scarcity of experts in rare disorders, higher costs of supplies, underfunding, and limited patient advocacy groups. Establishing collaborations among patient advocacy groups, governments, investigators, and other stakeholders to create action plans can address many of these issues and promote research into rare diseases.

    View details for DOI 10.1007/s12687-024-00759-y

    View details for PubMedID 39671061

    View details for PubMedCentralID 10562568

  • Laronidase-loaded liposomes reach the brain and other hard-to-treat organs after noninvasive nasal administration. International journal of pharmaceutics Schuh, R. S., Franceschi, E. P., Brum, B. B., Fachel, F. N., Poletto, É., Vera, L. N., Santos, H. S., Medeiros-Neves, B., Monteagudo de Barros, V., Helena da Rosa Paz, A., Baldo, G., Matte, U., Giugliani, R., Ferreira Teixeira, H. 2024: 124355

    Abstract

    Mucopolysaccharidosis type I (MPS I) is caused by lack of the lysosomal enzyme α-L-iduronidase (IDUA), responsible for the degradation of the glycosaminoglycans (GAGs) dermatan and heparan sulfate, leading to multisystemic signs and symptoms. Enzyme replacement therapy (ERT) is a treatment that consists of weekly intravenous administrations of laronidase, a recombinant version of IDUA. However, ERT have limited access to certain tissues, such as bone, cartilage, and brain, and laronidase fails to trespass the BBB. In this sense, this study reports the development and characterization of laronidase-loaded liposomes for the treatment of MPS I mice. Liposomal complexes were obtained by the thin film formation method followed by microfluidization. The main characterization results showed vesicle size of 103.0 ± 3.3 nm, monodisperse populations of vesicles, zeta potential around + 30.0 ± 2.1 mV, and mucoadhesion strength of 5.69 ± 0.14 mN. Treatment of MPS I mouse fibroblasts showed significant increase in enzyme activity. Nasal administration of complexes to MPS I mice resulted in significant increase in laronidase activity in the brain cortex, heart, lungs, kidneys, eyes, and serum. The overall results demonstrate the feasibility of nasal administration of laronidase-loaded liposomes to deliver enzyme in difficult-to-reach tissues, circumventing ERT issues and bringing hope as a potential treatment for MPS I.

    View details for DOI 10.1016/j.ijpharm.2024.124355

    View details for PubMedID 38897489

  • Clinical development of autologous genome-edited hematopoietic stem cells to treat mucopolysaccharidosis type I Poletto, E., Marathe, M., Margittai, D., Liu, X., Jiang, Q., Deshpande, T., Fazeli, F., Ikeda, T., Van Horn, T., Gomez-Ospina, N. ACADEMIC PRESS INC ELSEVIER SCIENCE. 2024
  • Genome-edited hematopoietic stem cells as a curative approach for Gaucher disease type 1 Vera, L., Gastou, M., Arozqueta-Basurto, J., Colella, P., Feng, A., Poletto, E., Gomez-Ospina, N. ACADEMIC PRESS INC ELSEVIER SCIENCE. 2024
  • Editorial: Genome editing in stem cells. Frontiers in genome editing Bayarsaikhan, D., Poletto, E. 2024; 6: 1357369

    View details for DOI 10.3389/fgeed.2024.1357369

    View details for PubMedID 38304247

  • Pilot study of newborn screening for six lysosomal diseases in Brazil MOLECULAR GENETICS AND METABOLISM Kubaski, F., Sousa, I., Amorim, T., Pereira, D., Silva, C., Chaves, V., Brusius-Facchin, A., Netto, A. O., Soares, J., Vairo, F., Poletto, E., Trometer, J., Souza, A., Ranieri, E., Polo, G., Hong, X., Herbst, Z. M., Burlina, A., Gelb, M. H., Giugliani, R. 2023; 140 (1-2): 107654

    Abstract

    Lysosomal diseases (LDs) are progressive life-threatening disorders that are usually asymptomatic at birth. Specific treatments are available for several LDs, and early intervention improves patient's outcomes. Thus, these diseases benefit from newborn screening (NBS). We have performed a pilot study for six LDs in Brazil by tandem mass spectrometry.Dried blood spot (DBS) samples of unselected newborns were analyzed by the Neo-LSD™ kit (Perkin-Elmer) by MS/MS. Samples with low enzyme activity were submitted to the evaluation of specific biomarkers by ultra-performance liquid chromatography tandem-mass spectrometry as the second-tier, and were analyzed by a next-generation sequencing (NGS) multi-gene panel as the third-tier. All tests were performed in the same DBS sample.In 20,066 newborns analyzed, 15 samples showed activity of one enzyme below the cutoff. Two newborns had biochemical and molecular results compatible with Fabry disease, and five newborns had biochemical results and pathogenic variants or variants of unknown significance (VUS) in GAA.This study indicates that the use of enzyme assay as the first-tier test gives an acceptably low number of positive results that requires second/third tier testing. The possibility to run all tests in a DBS sample makes this protocol applicable to large-scale NBS programs.

    View details for DOI 10.1016/j.ymgme.2023.107654

    View details for Web of Science ID 001123690900001

    View details for PubMedID 37507255

  • Microglia Replacement with Bone Marrow-Derived Cells after Transient Inhibition of the Colony-Stimulating Factor 1 Receptor (CSF1R) is Superior to Standard Myeloablative Conditioning in Neuropathic Lysosomal Storage Diseases Colella, P., Suarez-Nieto, M., Sayana, R., Poletto, E., Vera, L., Basurto, J., Gomez-Ospina, N. CELL PRESS. 2023: 160-161
  • Engineering Human Hematopoietic Stem and Progenitor Cells for Lineage-Specific Expression of Galactocerebrosidase Using Genome Editing Amorin, N. A., Golden, L., Poletto, E., Johnston, N., Feist, W., Menezes, T., Kikuta, K., Luna, S., Charlton, C., Kashuv, T., Gomez-Ospina, N. CELL PRESS. 2023: 782
  • Ex vivo gene therapy for lysosomal storage disorders: future perspectives EXPERT OPINION ON BIOLOGICAL THERAPY Poletto, E., Silva, A., Weinlich, R., Martin, P., Torres, D., Giugliani, R., Baldo, G. 2023: 1-12

    Abstract

    Lysosomal storage disorders (LSD) are a group of monogenic rare diseases caused by pathogenic variants in genes that encode proteins related to lysosomal function. These disorders are good candidates for gene therapy for different reasons: they are monogenic, most of lysosomal proteins are enzymes that can be secreted and cross-correct neighboring cells, and small quantities of these proteins are able to produce clinical benefits in many cases. Ex vivo gene therapy allows for autologous transplant of modified cells from different sources, including stem cells and hematopoietic precursors.Here, we summarize the main gene therapy and genome editing strategies that are currently being used as ex vivo gene therapy approaches for lysosomal disorders, highlighting important characteristics, such as vectors used, strategies, types of cells that are modified and main results in different disorders.Clinical trials are already ongoing, and soon approved therapies for LSD based on ex vivo gene therapy approaches should reach the market.

    View details for DOI 10.1080/14712598.2023.2192348

    View details for Web of Science ID 000954082500001

    View details for PubMedID 36920351

  • Diagnosis and Emerging Treatment Strategies for Mucopolysaccharidosis VII (Sly Syndrome). Therapeutics and clinical risk management Poswar, F. d., Henriques Nehm, J., Kubaski, F., Poletto, E., Giugliani, R. 2022; 18: 1143-1155

    Abstract

    Mucopolysaccharidosis VII (MPS VII, Sly syndrome) is an ultra-rare lysosomal disease caused by a deficiency of the enzyme β-glucuronidase (GUS). The diagnosis is suspected based on a range of symptoms that are common to many other MPS types, and it is confirmed through biochemical and molecular studies. Besides supportive treatment, current and emerging treatments include enzyme replacement therapy, hematopoietic stem cell transplantation, and gene therapy. This review summarizes the clinical manifestations, diagnosis, and emerging treatments for MPS VII.

    View details for DOI 10.2147/TCRM.S351300

    View details for PubMedID 36578769

    View details for PubMedCentralID PMC9791935

  • Experience of the NPC Brazil Network with a Comprehensive Program for the Screening and Diagnosis of Niemann-Pick Disease Type C INTERNATIONAL JOURNAL OF NEONATAL SCREENING Kubaski, F., Burlina, A., Polo, G., Pereira, D., Herbst, Z. M., Silva, C., Trapp, F. B., Michelin-Tirelli, K., Lopes, F. F., Burin, M. G., Brusius-Facchin, A., Netto, A. O., Faqueti, L., Iop, G. D., Poletto, E., Giugliani, R. 2022; 8 (3)

    Abstract

    Niemann-Pick disease type C (NPC) is a lysosomal disorder caused by impaired cholesterol metabolism. Levels of lysosphingomyelin 509 (LysoSM509) have been shown elevated in dried blood spots (DBS) of NPC and acid sphingomyelinase deficiency patients. In this study, we report our experience using a two-tier approach (1st tier is the quantification of lysoSM509 by ultra-performance liquid chromatography tandem mass spectrometry followed by the 2nd tier with next-generation sequencing of the NPC1 and NPC2 genes). DBS samples from 450 suspected patients were received by the NPC Brazil network. Of these, 33 samples had elevated levels of lysoSM509, and in 25 of them, variants classified as pathogenic, likely pathogenic, or of unknown significance were identified in the NPC1 or NPC2 genes by next-generation sequencing. The quantification of lysoSM509 in DBS as a first-tier test for the diagnosis of NPC followed by molecular analysis of the NPC1 and NPC2 genes almost doubled the detection rate when compared to the performance of chitotriosidase activity as a first-tier biomarker, and it could likely be increased with the addition of a third tier with MLPA of the two genes involved. This strategy seems suitable for the neonatal screening (NBS) of NPC if this disease is eventually adopted by NBS programs.

    View details for DOI 10.3390/ijns8030039

    View details for Web of Science ID 000858300700001

    View details for PubMedID 35892469

    View details for PubMedCentralID PMC9326630

  • Biochemical diagnosis of aromatic-L-amino acid decarboxylase deficiency (AADCD) by assay of AADC activity in plasma using liquid chromatography/tandem mass spectrometry MOLECULAR GENETICS AND METABOLISM REPORTS Civallero, G., Kubaski, F., Pereira, D., Rubensam, G., Herbst, Z. M., Silva, C., Trapp, F. B., Poletto, E., Faqueti, L., Iop, G., Soares, J., van der Linden, V., van der Linden, H., Lourenco, C. M., Giugliani, R. 2022; 32: 100888

    Abstract

    Aromatic l-amino acid decarboxylase (AADC, EC 4.1.1.28) deficiency is a rare genetic disorder characterized by developmental delay, oculogyric crises, autonomic dysfunction and other problems, caused by biallelic mutations in the DDC gene leading to deficient activity of aromatic l-amino acid decarboxylase, an enzyme involved in the formation of important neurotransmitters, such as dopamine and serotonin. A clinical development program of gene therapy for AADC deficiency is ongoing. An important step for the success of this therapy is the early and precise identification of the affected individuals, but it has been estimated that around 90% of the cases remain undiagnosed. The availability measurement of the AADC activity is mandatory for an accurate biochemical diagnosis. Based on these statements, our objectives were to develop a liquid chromatography tandem mass spectrometry (LC-MS/MS) method suitable for the determination of the AADC activity, and to evaluate its capacity to confirm the deficiency of AADC in potential patients in Brazil. The AADC activities were measured in plasma samples of seven AADC deficient patients and 35 healthy controls, after enzymatic reaction and LC-MS/MS analysis of dopamine, the main reaction product. The results obtained showed clear discrimination between confirmed AADC deficient patients and healthy controls. The method presented here could be incorporated in the IEM laboratories for confirmation of the diagnosis of when a suspicion of AADC deficiency is present due to clinical signs and/or abnormal biomarkers, including when an increased level of 3-O-methyldopa (3-OMD) is found in dried blood spots (DBS) samples from high-risk patients or from newborn screening programs.

    View details for DOI 10.1016/j.ymgmr.2022.100888

    View details for Web of Science ID 000836463600003

    View details for PubMedID 35769135

    View details for PubMedCentralID PMC9234702