Pioneering gene therapy trials have shown that the genetic engineering of haematopoietic stem and progenitor cells can be an alternative to allogeneic transplantation in the treatment of primary ...immunodeficiencies. Early trials also highlighted the risk of insertional mutagenesis and oncogene transactivation associated with the first generation of gammaretroviral vectors. These events prompted the development of safer, self-inactivating lentiviral or gammaretroviral vectors. These lentiviral vectors have been successfully used to treat over 200 patients with 10 different haematological disorders (including primary immunodeficiencies, haemoglobinopathies and metabolic disorders) and for the generation of chimeric antigen receptor-T cells for cancer therapy. However, several challenges, such as effective reconstitution during inflammation, remain if gene therapy is to be extended to more complex diseases in which haematopoietic stem and progenitor cells can be altered by the disease environment. We discuss the progress made and future challenges for gene therapy and contrast gene therapy with gene-editing strategies.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Gene Therapy in a Patient with Sickle Cell Disease Ribeil, Jean-Antoine; Hacein-Bey-Abina, Salima; Payen, Emmanuel ...
The New England journal of medicine,
03/2017, Volume:
376, Issue:
9
Journal Article
Peer reviewed
Open access
A boy with hydroxyurea-refractory sickle cell anemia underwent bone marrow transplantation with autologous hematopoietic stem cells transduced by a lentivirus to express an antisickling β-globin ...variant. No sickle cell crises occurred in the following 15 months.
Sickle cell disease is among the most prevalent inherited monogenic disorders. Approximately 90,000 people in the United States have sickle cell disease, and worldwide more than 275,000 infants are born with the disease annually.
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,
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Sickle cell disease was the first disease for which the molecular basis was identified: a single amino acid substitution in “adult” βA-globin (Glu6Val) stemming from a single base substitution (A→T) in the first exon of the human βA-globin gene (
HBB
) was discovered in 1956.
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Sickle hemoglobin (HbS) polymerizes on deoxygenation, reducing the deformability of red cells. Patients have intensely painful vaso-occlusive . . .
The use of chimeric antigen receptor (CAR)-engineered regulatory T cells (Tregs) has emerged as a promising strategy to promote immune tolerance. However, in conventional T cells (Tconvs), CAR ...expression is often associated with tonic signaling, which can induce CAR-T cell dysfunction. The extent and effects of CAR tonic signaling vary greatly according to the expression intensity and intrinsic properties of the CAR. Here, we show that the 4-1BB CSD-associated tonic signal yields a more dramatic effect in CAR-Tregs than in CAR-Tconvs with respect to activation and proliferation. Compared to CD28 CAR-Tregs, 4-1BB CAR-Tregs exhibit decreased lineage stability and reduced in vivo suppressive capacities. Transient exposure of 4-1BB CAR-Tregs to a Treg stabilizing cocktail, including an mTOR inhibitor and vitamin C, during ex vivo expansion sharply improves their in vivo function and expansion after adoptive transfer. This study demonstrates that the negative effects of 4-1BB tonic signaling in Tregs can be mitigated by transient mTOR inhibition.
Thalassemia major and sickle cell disease are the two most widely disseminated hereditary hemoglobinopathies in the world. The outlook for affected individuals has improved in recent years due to ...advances in medical management in the prevention and treatment of complications. However, hematopoietic stem cell transplantation is still the only available curative option. The use of hematopoietic stem cell transplantation has been increasing, and outcomes today have substantially improved compared with the past three decades. Current experience world-wide is that more than 90% of patients now survive hematopoietic stem cell transplantation and disease-free survival is around 80%. However, only a few controlled trials have been reported, and decisions on patient selection for hematopoietic stem cell transplantation and transplant management remain principally dependent on data from retrospective analyses and on the clinical experience of the transplant centers. This consensus document from the European Blood and Marrow Transplantation Inborn Error Working Party and the Paediatric Diseases Working Party aims to report new data and provide consensus-based recommendations on indications for hematopoietic stem cell transplantation and transplant management.
Sickle cell disease (SCD) and transfusion-dependent β-thalassemia (TDT) are the most prevalent monogenic disorders worldwide. Trial HGB-205 ( NCT02151526 ) aimed at evaluating gene therapy by ...autologous CD34
cells transduced ex vivo with lentiviral vector BB305 that encodes the anti-sickling β
-globin expressed in the erythroid lineage. HGB-205 is a phase 1/2, open-label, single-arm, non-randomized interventional study of 2-year duration at a single center, followed by observation in long-term follow-up studies LTF-303 ( NCT02633943 ) and LTF-307 ( NCT04628585 ) for TDT and SCD, respectively. Inclusion and exclusion criteria were similar to those for allogeneic transplantation but restricted to patients lacking geno-identical, histocompatible donors. Four patients with TDT and three patients with SCD, ages 13-21 years, were treated after busulfan myeloablation 4.6-7.9 years ago, with a median follow-up of 4.5 years. Key primary endpoints included mortality, engraftment, replication-competent lentivirus and clonal dominance. No adverse events related to the drug product were observed. Clinical remission and remediation of biological hallmarks of the disease have been sustained in two of the three patients with SCD, and frequency of transfusions was reduced in the third. The patients with TDT are all transfusion free with improvement of dyserythropoiesis and iron overload.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Dear Editor, Wiskott–Aldrich syndrome (WAS) is a severe X-linked primary immunodeficiency disorder with an incidence of between 1 in 50 000 and 1 in 250 000 live births.1,2 The syndrome is caused by ...loss-of-function mutations in the WAS gene that impair or abolish expression of the WAS protein (WASp).3 There is a genotype-phenotype correlation; the severity of the clinical phenotype and thus the most appropriate treatment can be predicted from the type of gene mutation and the latter's impact on WASp levels.4–6 The WAS severity score is based on the severity of thrombocytopenia (scored 0.5 or 1), the severity of eczema and immunodeficiency (scored from 2 to 4) and the presence of autoimmunity or malignancy (scored 5).7 WASp is a key regulator of the actin cytoskeleton. ...patients who fully lack WASp do not survive beyond their second or third decade of life.14 In 1968, WAS was the first primary immunodeficiency to be cured via HSCT.15 Since then, several large, retrospective analyses have evidenced impressive improvements in overall and event-free survival rates. ...impressive results in the absence of adverse events have been obtained in two adults treated by gene therapy. ...thymic function was maintained in these two patients, showing that the immune compartment can be successfully rebuilt.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Background Hematopoietic stem cell transplantation remains the only treatment for most patients with severe combined immunodeficiencies (SCIDs) or other primary immunodeficiencies (non-SCID PIDs). ...Objective To analyze the long-term outcome of patients with SCID and non-SCID PID from European centers treated between 1968 and 2005. Methods The product-limit method estimated cumulative survival; the log-rank test compared survival between groups. A Cox proportional-hazard model evaluated the impact of independent predictors on patient survival. Results In patients with SCID, survival with genoidentical donors (n = 25) from 2000 to 2005 was 90%. Survival using a mismatched relative (n = 96) has improved (66%), similar to that using an unrelated donor (n = 46; 69%; P = .005). Transplantation after year 1995, a younger age, B+ phenotype, genoidentical and phenoidentical donors, absence of respiratory impairment, or viral infection before transplantation were associated with better prognosis on multivariate analysis. For non-SCID PID, in contrast with patients with SCID, we confirm that, in the 2000 to 2005 period, using an unrelated donor (n = 124) gave a 3-year survival rate similar to a genoidentical donor (n = 73), 79% for both. Survival was 76% in phenoidentical transplants (n = 23) and worse in mismatched related donor transplants (n = 47; 46%; P = .016). Conclusion This is the largest cohort study of such patients with the longest follow-up. Specific issues arise for different patient groups. Patients with B-SCID have worse survival than other patients with SCID, despite improvements in each group. For non-SCID PID, survival is worse than SCID, although more conditions are now treated. Individual disease categories now need to be analyzed so that disease-specific prognosis may be better understood and the best treatments planned.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
10.
Four decades of progress Cavazzana, Marina
Blood,
08/2022, Volume:
140, Issue:
7
Journal Article
Peer reviewed
Open access
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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