RESUMEN
ABSTRACT: In physiological conditions, few circulating hematopoietic stem/progenitor cells (cHSPCs) are present in the peripheral blood, but their contribution to human hematopoiesis remain unsolved. By integrating advanced immunophenotyping, single-cell transcriptional and functional profiling, and integration site (IS) clonal tracking, we unveiled the biological properties and the transcriptional features of human cHSPC subpopulations in relationship to their bone marrow (BM) counterpart. We found that cHSPCs reduced in cell count over aging and are enriched for primitive, lymphoid, and erythroid subpopulations, showing preactivated transcriptional and functional state. Moreover, cHSPCs have low expression of multiple BM-retention molecules but maintain their homing potential after xenotransplantation. By generating a comprehensive human organ-resident HSPC data set based on single-cell RNA sequencing data, we detected organ-specific seeding properties of the distinct trafficking HSPC subpopulations. Notably, circulating multi-lymphoid progenitors are primed for seeding the thymus and actively contribute to T-cell production. Human clonal tracking data from patients receiving gene therapy (GT) also showed that cHSPCs connect distant BM niches and participate in steady-state hematopoietic production, with primitive cHSPCs having the highest recirculation capability to travel in and out of the BM. Finally, in case of hematopoietic impairment, cHSPCs composition reflects the BM-HSPC content and might represent a biomarker of the BM state for clinical and research purposes. Overall, our comprehensive work unveiled fundamental insights into the in vivo dynamics of human HSPC trafficking and its role in sustaining hematopoietic homeostasis. GT patients' clinical trials were registered at ClinicalTrials.gov (NCT01515462 and NCT03837483) and EudraCT (2009-017346-32 and 2018-003842-18).
Asunto(s)
Hematopoyesis , Células Madre Hematopoyéticas , Homeostasis , Animales , Humanos , Ratones , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Análisis de la Célula IndividualRESUMEN
Common variable immunodeficiency (CVID) is the most frequent primary antibody deficiency whereby follicular helper T (Tfh) cells fail to establish productive responses with B cells in germinal centers. Here, we analyzed the frequency, phenotype, transcriptome, and function of circulating Tfh (cTfh) cells in CVID patients displaying autoimmunity as an additional phenotype. A group of patients showed a high frequency of cTfh1 cells and a prominent expression of PD-1 and ICOS as well as a cTfh mRNA signature consistent with highly activated, but exhausted, senescent, and apoptotic cells. Plasmatic CXCL13 levels were elevated in this group and positively correlated with cTfh1 cell frequency and PD-1 levels. Monoallelic variants in RTEL1, a telomere length- and DNA repair-related gene, were identified in four patients belonging to this group. Their blood lymphocytes showed shortened telomeres, while their cTfh were more prone to apoptosis. These data point toward a novel pathogenetic mechanism in CVID, whereby alterations in DNA repair and telomere elongation might predispose to antibody deficiency. A Th1, highly activated but exhausted and apoptotic cTfh phenotype was associated with this form of CVID.
Asunto(s)
Inmunodeficiencia Variable Común , Apoptosis/genética , Inmunodeficiencia Variable Común/genética , Humanos , Receptor de Muerte Celular Programada 1/genética , Células T Auxiliares Foliculares , Linfocitos T Colaboradores-InductoresRESUMEN
ARPC1B is a key factor for the assembly and maintenance of the ARP2/3 complex that is involved in actin branching from an existing filament. Germline biallelic mutations in ARPC1B have been recently described in 6 patients with clinical features of combined immunodeficiency (CID), whose neutrophils and platelets but not T lymphocytes were studied. We hypothesized that ARPC1B deficiency may also lead to cytoskeleton and functional defects in T cells. We have identified biallelic mutations in ARPC1B in 6 unrelated patients with early onset disease characterized by severe infections, autoimmune manifestations, and thrombocytopenia. Immunological features included T-cell lymphopenia, low numbers of naïve T cells, and hyper-immunoglobulin E. Alteration in ARPC1B protein structure led to absent/low expression by flow cytometry and confocal microscopy. This molecular defect was associated with the inability of patient-derived T cells to extend an actin-rich lamellipodia upon T-cell receptor (TCR) stimulation and to assemble an immunological synapse. ARPC1B-deficient T cells additionally displayed impaired TCR-mediated proliferation and SDF1-α-directed migration. Gene transfer of ARPC1B in patients' T cells using a lentiviral vector restored both ARPC1B expression and T-cell proliferation in vitro. In 2 of the patients, in vivo somatic reversion restored ARPC1B expression in a fraction of lymphocytes and was associated with a skewed TCR repertoire. In 1 revertant patient, memory CD8+ T cells expressing normal levels of ARPC1B displayed improved T-cell migration. Inherited ARPC1B deficiency therefore alters T-cell cytoskeletal dynamics and functions, contributing to the clinical features of CID.
Asunto(s)
Complejo 2-3 Proteico Relacionado con la Actina/genética , Mutación de Línea Germinal , Síndromes de Inmunodeficiencia/genética , Linfocitos T/patología , Complejo 2-3 Proteico Relacionado con la Actina/química , Femenino , Homocigoto , Humanos , Síndromes de Inmunodeficiencia/patología , Masculino , Modelos Moleculares , Linaje , Conformación Proteica , Inmunodeficiencia Combinada Grave/genética , Inmunodeficiencia Combinada Grave/patología , Linfocitos T/metabolismoRESUMEN
Adenosine deaminase (ADA) deficiency is a rare, autosomal-recessive systemic metabolic disease characterized by severe combined immunodeficiency (SCID). The treatment of choice for ADA-deficient SCID (ADA-SCID) is hematopoietic stem cell transplant from an HLA-matched sibling donor, although <25% of patients have such a donor available. Enzyme replacement therapy (ERT) partially and temporarily relieves immunodeficiency. We investigated the medium-term outcome of gene therapy (GT) in 18 patients with ADA-SCID for whom an HLA-identical family donor was not available; most were not responding well to ERT. Patients were treated with an autologous CD34(+)-enriched cell fraction that contained CD34(+) cells transduced with a retroviral vector encoding the human ADA complementary DNA sequence (GSK2696273) as part of single-arm, open-label studies or compassionate use programs. Overall survival was 100% over 2.3 to 13.4 years (median, 6.9 years). Gene-modified cells were stably present in multiple lineages throughout follow up. GT resulted in a sustained reduction in the severe infection rate from 1.17 events per person-year to 0.17 events per person-year (n = 17, patient 1 data not available). Immune reconstitution was demonstrated by normalization of T-cell subsets (CD3(+), CD4(+), and CD8(+)), evidence of thymopoiesis, and sustained T-cell proliferative capacity. B-cell function was evidenced by immunoglobulin production, decreased intravenous immunoglobulin use, and antibody response after vaccination. All 18 patients reported infections as adverse events; infections of respiratory and gastrointestinal tracts were reported most frequently. No events indicative of leukemic transformation were reported. Trial details were registered at www.clinicaltrials.gov as #NCT00598481.
Asunto(s)
Adenosina Desaminasa/deficiencia , Agammaglobulinemia/terapia , Terapia Genética , Recuperación de la Función , Retroviridae , Inmunodeficiencia Combinada Grave/terapia , Adenosina Desaminasa/genética , Adenosina Desaminasa/inmunología , Agammaglobulinemia/genética , Agammaglobulinemia/inmunología , Agammaglobulinemia/mortalidad , Linfocitos B/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Niño , Preescolar , Supervivencia sin Enfermedad , Femenino , Humanos , Lactante , Masculino , Inmunodeficiencia Combinada Grave/genética , Inmunodeficiencia Combinada Grave/inmunología , Inmunodeficiencia Combinada Grave/mortalidad , Tasa de SupervivenciaAsunto(s)
Adenosina Desaminasa/deficiencia , Agammaglobulinemia/terapia , Antivirales/uso terapéutico , Bencimidazoles/uso terapéutico , Fluorenos/uso terapéutico , Terapia Genética , Hepatitis C/tratamiento farmacológico , Inmunodeficiencia Combinada Grave/terapia , Uridina Monofosfato/análogos & derivados , Agammaglobulinemia/complicaciones , Humanos , Lactante , Masculino , Inmunodeficiencia Combinada Grave/complicaciones , Sofosbuvir , Uridina Monofosfato/uso terapéuticoRESUMEN
Hematopoietic stem cell gene therapy (GT) using a γ-retroviral vector (γ-RV) is an effective treatment for Severe Combined Immunodeficiency due to Adenosine Deaminase deficiency. Here, we describe a case of GT-related T-cell acute lymphoblastic leukemia (T-ALL) that developed 4.7 years after treatment. The patient underwent chemotherapy and haploidentical transplantation and is currently in remission. Blast cells contain a single vector insertion activating the LIM-only protein 2 (LMO2) proto-oncogene, confirmed by physical interaction, and low Adenosine Deaminase (ADA) activity resulting from methylation of viral promoter. The insertion is detected years before T-ALL in multiple lineages, suggesting that further hits occurred in a thymic progenitor. Blast cells contain known and novel somatic mutations as well as germline mutations which may have contributed to transformation. Before T-ALL onset, the insertion profile is similar to those of other ADA-deficient patients. The limited incidence of vector-related adverse events in ADA-deficiency compared to other γ-RV GT trials could be explained by differences in transgenes, background disease and patient's specific factors.
Asunto(s)
Adenosina Desaminasa , Agammaglobulinemia , Terapia Genética , Vectores Genéticos , Trasplante de Células Madre Hematopoyéticas , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Proto-Oncogenes Mas , Inmunodeficiencia Combinada Grave , Humanos , Adenosina Desaminasa/deficiencia , Adenosina Desaminasa/genética , Terapia Genética/métodos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Inmunodeficiencia Combinada Grave/terapia , Inmunodeficiencia Combinada Grave/genética , Vectores Genéticos/genética , Agammaglobulinemia/terapia , Agammaglobulinemia/genética , Masculino , Retroviridae/genéticaRESUMEN
Adenosine deaminase (ADA) deficiency leads to severe combined immunodeficiency (SCID). Previous clinical trials showed that autologous CD34+ cell gene therapy (GT) following busulfan reduced-intensity conditioning is a promising therapeutic approach for ADA-SCID, but long-term data are warranted. Here we report an analysis on long-term safety and efficacy data of 43 patients with ADA-SCID who received retroviral ex vivo bone marrow-derived hematopoietic stem cell GT. Twenty-two individuals (median follow-up 15.4 years) were treated in the context of clinical development or named patient program. Nineteen patients were treated post-marketing authorization (median follow-up 3.2 years), and two additional patients received mobilized peripheral blood CD34+ cell GT. At data cutoff, all 43 patients were alive, with a median follow-up of 5.0 years (interquartile range 2.4-15.4) and 2 years intervention-free survival (no need for long-term enzyme replacement therapy or allogeneic hematopoietic stem cell transplantation) of 88% (95% confidence interval 78.7-98.4%). Most adverse events/reactions were related to disease background, busulfan conditioning or immune reconstitution; the safety profile of the real world experience was in line with premarketing cohort. One patient from the named patient program developed a T cell leukemia related to treatment 4.7 years after GT and is currently in remission. Long-term persistence of multilineage gene-corrected cells, metabolic detoxification, immune reconstitution and decreased infection rates were observed. Estimated mixed-effects models showed that higher dose of CD34+ cells infused and younger age at GT affected positively the plateau of CD3+ transduced cells, lymphocytes and CD4+ CD45RA+ naive T cells, whereas the cell dose positively influenced the final plateau of CD15+ transduced cells. These long-term data suggest that the risk-benefit of GT in ADA remains favorable and warrant for continuing long-term safety monitoring. Clinical trial registration: NCT00598481 , NCT03478670 .
Asunto(s)
Agammaglobulinemia , Trasplante de Células Madre Hematopoyéticas , Inmunodeficiencia Combinada Grave , Humanos , Inmunodeficiencia Combinada Grave/genética , Inmunodeficiencia Combinada Grave/terapia , Adenosina Desaminasa/genética , Adenosina Desaminasa/uso terapéutico , Busulfano/efectos adversos , Terapia Genética , Retroviridae/genéticaRESUMEN
Mobilized peripheral blood is increasingly used instead of bone marrow as a source of autologous hematopoietic stem/progenitor cells for ex vivo gene therapy. Here, we present an unplanned exploratory analysis evaluating the hematopoietic reconstitution kinetics, engraftment and clonality in 13 pediatric Wiskott-Aldrich syndrome patients treated with autologous lentiviral-vector transduced hematopoietic stem/progenitor cells derived from mobilized peripheral blood (n = 7), bone marrow (n = 5) or the combination of the two sources (n = 1). 8 out of 13 gene therapy patients were enrolled in an open-label, non-randomized, phase 1/2 clinical study (NCT01515462) and the remaining 5 patients were treated under expanded access programs. Although mobilized peripheral blood- and bone marrow- hematopoietic stem/progenitor cells display similar capability of being gene-corrected, maintaining the engineered grafts up to 3 years after gene therapy, mobilized peripheral blood-gene therapy group shows faster neutrophil and platelet recovery, higher number of engrafted clones and increased gene correction in the myeloid lineage which correlate with higher amount of primitive and myeloid progenitors contained in hematopoietic stem/progenitor cells derived from mobilized peripheral blood. In vitro differentiation and transplantation studies in mice confirm that primitive hematopoietic stem/progenitor cells from both sources have comparable engraftment and multilineage differentiation potential. Altogether, our analyses reveal that the differential behavior after gene therapy of hematopoietic stem/progenitor cells derived from either bone marrow or mobilized peripheral blood is mainly due to the distinct cell composition rather than functional differences of the infused cell products, providing new frames of references for clinical interpretation of hematopoietic stem/progenitor cell transplantation outcome.
Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Síndrome de Wiskott-Aldrich , Humanos , Niño , Animales , Ratones , Médula Ósea , Células Madre Hematopoyéticas , Terapia Genética , Síndrome de Wiskott-Aldrich/genética , Factor Estimulante de Colonias de GranulocitosRESUMEN
In this work we present the case of SARS-CoV-2 infection in a 1.5-year-old boy affected by severe Wiskott-Aldrich Syndrome with previous history of autoinflammatory disease, occurring 5 months after treatment with gene therapy. Before SARS-CoV-2 infection, the patient had obtained engraftment of gene corrected cells, resulting in WASP expression restoration and early immune reconstitution. The patient produced specific immunoglobulins to SARS-CoV-2 at high titer with neutralizing capacity and experienced a mild course of infection, with limited inflammatory complications, despite pre-gene therapy clinical phenotype.
Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19 , Terapia Genética , SARS-CoV-2 , Síndrome de Wiskott-Aldrich , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , COVID-19/sangre , COVID-19/inmunología , COVID-19/terapia , Humanos , Lactante , Masculino , SARS-CoV-2/inmunología , SARS-CoV-2/metabolismo , Síndrome de Wiskott-Aldrich/sangre , Síndrome de Wiskott-Aldrich/inmunología , Síndrome de Wiskott-Aldrich/terapia , Proteína del Síndrome de Wiskott-Aldrich/biosíntesis , Proteína del Síndrome de Wiskott-Aldrich/inmunologíaRESUMEN
BACKGROUND: Wiskott-Aldrich syndrome is a rare, life-threatening, X-linked primary immunodeficiency characterised by microthrombocytopenia, infections, eczema, autoimmunity, and malignant disease. Lentiviral vector-mediated haemopoietic stem/progenitor cell (HSPC) gene therapy is a potentially curative treatment that represents an alternative to allogeneic HSPC transplantation. Here, we report safety and efficacy data from an interim analysis of patients with severe Wiskott-Aldrich syndrome who received lentiviral vector-derived gene therapy. METHODS: We did a non-randomised, open-label, phase 1/2 clinical study in paediatric patients with severe Wiskott-Aldrich syndrome, defined by either WAS gene mutation or absent Wiskott-Aldrich syndrome protein (WASP) expression or a Zhu clinical score of 3 or higher. We included patients who had no HLA-identical sibling donor available or, for children younger than 5 years of age, no suitable 10/10 matched unrelated donor or 6/6 unrelated cord blood donor. After treatment with rituximab and a reduced-intensity conditioning regimen of busulfan and fludarabine, patients received one intravenous infusion of autologous CD34+ cells genetically modified with a lentiviral vector encoding for human WAS cDNA. The primary safety endpoints were safety of the conditioning regimen and safety of lentiviral gene transfer into HSPCs. The primary efficacy endpoints were overall survival, sustained engraftment of genetically corrected HSPCs, expression of vector-derived WASP, improved T-cell function, antigen-specific responses to vaccinations, and improved platelet count and mean platelet volume normalisation. This interim analysis was done when the first six patients treated had completed at least 3 years of follow-up. The planned analyses are presented for the intention-to-treat population. This trial is registered with ClinicalTrials.gov (number NCT01515462) and EudraCT (number 2009-017346-32). FINDINGS: Between April 20, 2010, and Feb 26, 2015, nine patients (all male) were enrolled of whom one was excluded after screening; the age range of the eight treated children was 1·1-12·4 years. At the time of the interim analysis (data cutoff April 29, 2016), median follow-up was 3·6 years (range 0·5-5·6). Overall survival was 100%. Engraftment of genetically corrected HSPCs was successful and sustained in all patients. The fraction of WASP-positive lymphocytes increased from a median of 3·9% (range 1·8-35·6) before gene therapy to 66·7% (55·7-98·6) at 12 months after gene therapy, whereas WASP-positive platelets increased from 19·1% (range 4·1-31·0) to 76·6% (53·1-98·4). Improvement of immune function was shown by normalisation of in-vitro T-cell function and successful discontinuation of immunoglobulin supplementation in seven patients with follow-up longer than 1 year, followed by positive antigen-specific response to vaccination. Severe infections fell from 2·38 (95% CI 1·44-3·72) per patient-year of observation (PYO) in the year before gene therapy to 0·31 (0·04-1·11) per PYO in the second year after gene therapy and 0·17 (0·00-0·93) per PYO in the third year after gene therapy. Before gene therapy, platelet counts were lower than 20â×â109 per L in seven of eight patients. At the last follow-up visit, the platelet count had increased to 20-50â×â109 per L in one patient, 50-100â×â109 per L in five patients, and more than 100â×â109 per L in two patients, which resulted in independence from platelet transfusions and absence of severe bleeding events. 27 serious adverse events in six patients occurred after gene therapy, 23 (85%) of which were infectious (pyrexia [five events in three patients], device-related infections, including one case of sepsis [four events in three patients], and gastroenteritis, including one case due to rotavirus [three events in two patients]); these occurred mainly in the first 6 months of follow-up. No adverse reactions to the investigational drug product and no abnormal clonal proliferation or leukaemia were reported after gene therapy. INTERPRETATION: Data from this study show that gene therapy provides a valuable treatment option for patients with severe Wiskott-Aldrich syndrome, particularly for those who do not have a suitable HSPC donor available. FUNDING: Italian Telethon Foundation, GlaxoSmithKline, and Orchard Therapeutics.
Asunto(s)
Terapia Genética , Vectores Genéticos/genética , Células Madre Hematopoyéticas/metabolismo , Lentivirus/genética , Síndrome de Wiskott-Aldrich/genética , Síndrome de Wiskott-Aldrich/terapia , Niño , Preescolar , Femenino , Terapia Genética/métodos , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Lactante , Italia , Masculino , Mutación , Linfocitos T/inmunología , Linfocitos T/metabolismo , Acondicionamiento Pretrasplante/métodos , Resultado del Tratamiento , Síndrome de Wiskott-Aldrich/sangre , Síndrome de Wiskott-Aldrich/diagnóstico , Proteína del Síndrome de Wiskott-Aldrich/genéticaRESUMEN
Hematopoietic stem and progenitor cells (HSPC) are endowed with the role of generating and maintaining lifelong the extremely diverse pool of blood cells1. Clinically, transplantation of human HSPC from an allogeneic healthy donor or infusion of autologous gene-corrected HSPC can effectively replenish defective blood cell production caused by congenital or acquired disorders2-9. However, due to methodological and ethical constraints that have limited the study of human HSPC primarily to in vitro assays10 or xenotransplantation models11,12, the in vivo activity of HSPC has to date remained relatively unexplored in humans13-16. Here we report a comprehensive study of the frequencies, dynamics and output of seven HSPC subtypes in humans that was performed by tracking 148,093 individual clones in six patients treated with lentiviral gene therapy using autologous HSPC transplantation and followed for up to 5 years. We discovered that primitive multipotent progenitor and hematopoietic stem cell (HSC) populations have distinct roles during the initial reconstitution after transplant, compared with subsequent steady-state phases. Furthermore, we showed that a fraction of in vitro-activated HSC are resilient and undergo a defined delayed activation period upon transplant. Finally, our data support the concept that early lymphoid-biased progenitors might be capable of long-term survival, such that they can be maintained independently of their continuous production from HSC. Overall, this study provides comprehensive data on HSPC dynamics after autologous transplantation and gene therapy in humans.
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Ingeniería Genética , Terapia Genética , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/citología , Células Sanguíneas/citología , Células Sanguíneas/trasplante , Linaje de la Célula/genética , Vectores Genéticos/uso terapéutico , Células Madre Hematopoyéticas/metabolismo , Humanos , Lentivirus/genética , Células Madre/citología , Trasplante Autólogo/efectos adversosRESUMEN
Adenosine deaminase-deficient severe combined immunodeficiency disease (ADA-SCID) is a primary immune deficiency characterized by mutations in the ADA gene resulting in accumulation of toxic compounds affecting multiple districts. Hematopoietic stem cell transplantation (HSCT) from a matched donor and hematopoietic stem cell gene therapy are the preferred options for definitive treatment. Enzyme replacement therapy (ERT) is used to manage the disease in the short term, while a decreased efficacy is reported in the medium-long term. To date, eight cases of lymphomas have been described in ADA-SCID patients. Here we report the first case of plasmablastic lymphoma occurring in a young adult with ADA-SCID on long-term ERT, which turned out to be Epstein-Barr virus associated. The patient previously received infusions of genetically modified T cells. A cumulative analysis of the eight published cases of lymphoma from 1992 to date, and the case here described, reveals a high mortality (89%). The most common form is diffuse large B-cell lymphoma, which predominantly occurs in extra nodal sites. Seven cases occurred in patients on ERT and two after haploidentical HSCT. The significant incidence of immunodeficiency-associated lymphoproliferative disorders and poor survival of patients developing this complication highlight the priority in finding a prompt curative treatment for ADA-SCID.
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Adenosina Desaminasa/deficiencia , Agammaglobulinemia/complicaciones , Infecciones por Virus de Epstein-Barr/complicaciones , Linfoma Plasmablástico/etiología , Inmunodeficiencia Combinada Grave/complicaciones , Adenosina Desaminasa/uso terapéutico , Adolescente , Agammaglobulinemia/tratamiento farmacológico , Agammaglobulinemia/etiología , Terapia de Reemplazo Enzimático , Resultado Fatal , Femenino , Humanos , Linfoma Plasmablástico/diagnóstico , Inmunodeficiencia Combinada Grave/tratamiento farmacológico , Inmunodeficiencia Combinada Grave/etiologíaRESUMEN
Hematopoietic stem/progenitor cells (HSPCs) are capable of supporting the lifelong production of blood cells exerting a wide spectrum of functions. Lentiviral vector HSPC gene therapy generates a human hematopoietic system stably marked at the clonal level by vector integration sites (ISs). Using IS analysis, we longitudinally tracked >89,000 clones from 15 distinct bone marrow and peripheral blood lineages purified up to 4 years after transplant in four Wiskott-Aldrich syndrome patients treated with HSPC gene therapy. We measured at the clonal level repopulating waves, populations' sizes and dynamics, activity of distinct HSPC subtypes, contribution of various progenitor classes during the early and late post-transplant phases, and hierarchical relationships among lineages. We discovered that in-vitro-manipulated HSPCs retain the ability to return to latency after transplant and can be physiologically reactivated, sustaining a stable hematopoietic output. This study constitutes in vivo comprehensive tracking in humans of hematopoietic clonal dynamics during the early and late post-transplant phases.
Asunto(s)
Rastreo Celular , Hematopoyesis , Antígenos CD34/metabolismo , Ingeniería Celular , Linaje de la Célula/genética , Preescolar , Células Clonales , Terapia Genética , Hematopoyesis/genética , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Humanos , Lactante , Masculino , Células Madre Multipotentes/citología , Células Madre Multipotentes/metabolismo , Mutagénesis Insercional/genética , Factores de Tiempo , Síndrome de Wiskott-Aldrich/genética , Síndrome de Wiskott-Aldrich/terapiaRESUMEN
A definitive understanding of survival and differentiation potential in humans of T cell subpopulations is of paramount importance for the development of effective T cell therapies. In particular, uncovering the dynamics in vivo in humans of the recently described T memory stem cells (TSCM) would be crucial for therapeutic approaches that aim at taking advantage of a stable cellular vehicle with precursor potential. We exploited data derived from two gene therapy clinical trials for an inherited immunodeficiency, using either retrovirally engineered hematopoietic stem cells or mature lymphocytes to trace individual T cell clones directly in vivo in humans. We compared healthy donors and bone marrow-transplanted patients, studied long-term in vivo T cell composition under different clinical conditions, and specifically examined TSCM contribution according to age, conditioning regimen, disease background, cell source, long-term reconstitution, and ex vivo gene correction processing. High-throughput sequencing of retroviral vector integration sites (ISs) allowed tracing the fate of more than 1700 individual T cell clones in gene therapy patients after infusion of gene-corrected hematopoietic stem cells or mature lymphocytes. We shed light on long-term in vivo clonal relationships among different T cell subtypes, and we unveiled that TSCM are able to persist and to preserve their precursor potential in humans for up to 12 years after infusion of gene-corrected lymphocytes. Overall, this work provides high-resolution tracking of T cell fate and activity and validates, in humans, the safe and functional decade-long survival of engineered TSCM, paving the way for their future application in clinical settings.
Asunto(s)
Rastreo Celular , Ingeniería Genética , Células Madre Hematopoyéticas/citología , Memoria Inmunológica , Linfocitos T/citología , Linfocitos T/metabolismo , Adulto , Supervivencia Celular , Niño , Células Clonales , Terapia Genética , Humanos , Interleucina-2/farmacología , Estudios Longitudinales , Subgrupos Linfocitarios/metabolismo , Fenotipo , Acetato de Tetradecanoilforbol/farmacología , Factores de Tiempo , Donantes de TejidosRESUMEN
Long-lasting immune protection from pathogens and cancer requires the generation of memory T cells able to survive long-term. To unravel the immunological requirements for long-term persistence of human memory T cells, we characterized and traced, over several years, T lymphocytes genetically modified to express the thymidine kinase (TK) suicide gene that were infused in 10 patients after haploidentical hematopoietic stem cell transplantation (HSCT). At 2 to 14 years after infusion and in the presence of a broad and resting immune system, we could still detect effectors/effector memory (TEM/EFF), central memory (TCM), and stem memory (TSCM) TK(+) cells, circulating at low but stable levels in all patients. Longitudinal analysis of cytomegalovirus (CMV)- and Flu-specific TK(+) cells indicated that antigen recognition was dominant in driving in vivo expansion and persistence at detectable levels. The amount of infused TSCM cells positively correlated with early expansion and with the absolute counts of long-term persisting gene-marked cells. By combining T cell sorting with sequencing of integration (IS), TCRα and TCRß clonal markers, we showed that T cells retrieved long-term were enriched in clones originally shared in different memory T cell subsets, whereas dominant long-term clonotypes appeared to preferentially originate from infused TSCM and TCM clones. Together, these results indicate that long-term persistence of gene-modified memory T cells after haploidentical HSCT is influenced by antigen exposure and by the original phenotype of infused cells. Cancer adoptive immunotherapy might thus benefit from cellular products enriched in lymphocytes with an early-differentiated phenotype.
Asunto(s)
Rastreo Celular , Ingeniería Genética , Memoria Inmunológica , Linfocitos T/inmunología , Adulto , Anciano , Antígenos/inmunología , Proliferación Celular , Células Clonales , Femenino , Genes Transgénicos Suicidas , Terapia Genética , Trasplante de Células Madre Hematopoyéticas , Humanos , Recuento de Linfocitos , Depleción Linfocítica , Masculino , Persona de Mediana Edad , Fenotipo , Timidina Quinasa/metabolismo , Factores de Tiempo , Donantes de Tejidos , Adulto JovenRESUMEN
Wiskott-Aldrich syndrome (WAS) is an inherited immunodeficiency caused by mutations in the gene encoding WASP, a protein regulating the cytoskeleton. Hematopoietic stem/progenitor cell (HSPC) transplants can be curative, but, when matched donors are unavailable, infusion of autologous HSPCs modified ex vivo by gene therapy is an alternative approach. We used a lentiviral vector encoding functional WASP to genetically correct HSPCs from three WAS patients and reinfused the cells after a reduced-intensity conditioning regimen. All three patients showed stable engraftment of WASP-expressing cells and improvements in platelet counts, immune functions, and clinical scores. Vector integration analyses revealed highly polyclonal and multilineage haematopoiesis resulting from the gene-corrected HSPCs. Lentiviral gene therapy did not induce selection of integrations near oncogenes, and no aberrant clonal expansion was observed after 20 to 32 months. Although extended clinical observation is required to establish long-term safety, lentiviral gene therapy represents a promising treatment for WAS.