Diagnostic assay to assist clinical decisions for unclassified severe combined immune deficiency

Bifsha, Panojot; Leiding, Jennifer W.; Pai, Sung Yun; Colamartino, Aurélien; Hartog, Nicholas; Church, Joseph A.; Oshrine, Benjamin; Puck, Jennifer M.; Markert, M. Louise; Haddad, Élie

doi:10.1182/bloodadvances.2020001736

Cited by 33 publications

(43 citation statements)

References 9 publications

(8 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We reported a similar loss of DP cells over time when co-culturing induced pluripotent stem cell-derived CD34 1 cells from patients with RAG-null mutations with OP9-DLL4 cells, concurrent with an accumulation of single-strand DNA breaks and impaired cell survival. 17 A similar mechanism may account for the lack of DP cells in patients with SCID and Omenn syndrome observed by Bifsha et al 16 at week 5. In vivo, such decline in the number of DP cells could contribute to the lack of circulating TCRab 1 CD3 1 cells in SCID patients.…”

Section: Discussionmentioning

confidence: 69%

“…In this article, we describe our observation of a similar block in T-cell development at the DP stage in patients with RAG deficiency, irrespective of the severity of their clinical and immunologic phenotype. In a companion article, Bifsha et al 16 reported a difference in the capacity of CD34 1 cells from patients with RAG deficiency manifesting as SCID or Omenn syndrome to generate DP cells. We reported a similar loss of DP cells over time when co-culturing induced pluripotent stem cell-derived CD34 1 cells from patients with RAG-null mutations with OP9-DLL4 cells, concurrent with an accumulation of single-strand DNA breaks and impaired cell survival.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Artificial thymic organoids represent a reliable tool to study T-cell differentiation in patients with severe T-cell lymphopenia

et al. 2020

Self Cite

View full text Add to dashboard Cite

The study of early T-cell development in humans is challenging because of limited availability of thymic samples and the limitations of in vitro T-cell differentiation assays. We used an artificial thymic organoid (ATO) platform generated by aggregating a DLL4-expressing stromal cell line (MS5-hDLL4) with CD34+ cells isolated from bone marrow or mobilized peripheral blood to study T-cell development from CD34+ cells of patients carrying hematopoietic intrinsic or thymic defects that cause T-cell lymphopenia. We found that AK2 deficiency is associated with decreased cell viability and an early block in T-cell development. We observed a similar defect in a patient carrying a null IL2RG mutation. In contrast, CD34+ cells from a patient carrying a missense IL2RG mutation reached full T-cell maturation, although cell numbers were significantly lower than in controls. CD34+ cells from patients carrying RAG mutations were able to differentiate to CD4+CD8+ cells, but not to CD3+TCRαβ+ cells. Finally, normal T-cell differentiation was observed in a patient with complete DiGeorge syndrome, consistent with the extra-hematopoietic nature of the defect. The ATO system may help determine whether T-cell deficiency reflects hematopoietic or thymic intrinsic abnormalities and define the exact stage at which T-cell differentiation is blocked.

show abstract

Section: Discussionmentioning

confidence: 69%

Section: Discussionmentioning

confidence: 99%

Artificial thymic organoids represent a reliable tool to study T-cell differentiation in patients with severe T-cell lymphopenia

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…We have taken advantage of a monolayer co-culture system of patients’ bone marrow-derived CD34 + cells together with OP9/DL1 stromal cells and growth factors ( 49 ). Recently, two groups reported the use of artificial thymic organoids aggregating DLL4-expressing stromal cell lines (OP9/DLL4 and MS5-hDLL4) to facilitate the differentiation of CD34 + cells, isolated either from the patients’ bone marrow aspirate ( 52 ) or from their peripheral blood ( 131 ). Using these three-dimensional tools, they have shown that CD34 + cells of two cDGS patients, one with a TBX1 mutation and the other with a deletion at chromosome 22q11.2, had the potential to differentiate into CD3 + mature T-cells, in line with their disorder not affecting the HSC.…”

Section: Abnormalities Of Thymic Stromal Development and Functionmentioning

confidence: 99%

Current and Future Therapeutic Approaches for Thymic Stromal Cell Defects

2021

View full text Add to dashboard Cite

Inborn errors of thymic stromal cell development and function lead to impaired T-cell development resulting in a susceptibility to opportunistic infections and autoimmunity. In their most severe form, congenital athymia, these disorders are life-threatening if left untreated. Athymia is rare and is typically associated with complete DiGeorge syndrome, which has multiple genetic and environmental etiologies. It is also found in rare cases of T-cell lymphopenia due to Nude SCID and Otofaciocervical Syndrome type 2, or in the context of genetically undefined defects. This group of disorders cannot be corrected by hematopoietic stem cell transplantation, but upon timely recognition as thymic defects, can successfully be treated by thymus transplantation using cultured postnatal thymic tissue with the generation of naïve T-cells showing a diverse repertoire. Mortality after this treatment usually occurs before immune reconstitution and is mainly associated with infections most often acquired pre-transplantation. In this review, we will discuss the current approaches to the diagnosis and management of thymic stromal cell defects, in particular those resulting in athymia. We will discuss the impact of the expanding implementation of newborn screening for T-cell lymphopenia, in combination with next generation sequencing, as well as the role of novel diagnostic tools distinguishing between hematopoietic and thymic stromal cell defects in facilitating the early consideration for thymus transplantation of an increasing number of patients and disorders. Immune reconstitution after the current treatment is usually incomplete with relatively common inflammatory and autoimmune complications, emphasizing the importance for improving strategies for thymus replacement therapy by optimizing the current use of postnatal thymus tissue and developing new approaches using engineered thymus tissue.

show abstract

“…T cell lymphopaenia may mistakenly be ascribed to an undefined haematopoietic defect and a thymic aetiology only suspected after absent immune reconstitution post-HSCT. Novel tools are emerging to facilitate the distinction of primary haematopoietic defects from inborn errors of thymic stromal cells in patients presenting with genetically undefined severe T cell lymphopaenia [ 126 , 129 , 146 , 147 ]. These include the use of artificial thymic organoids that express DLL4 and can therefore support the differentiation of CD34 + haematopoietic stem cells (HSCs) into mature T cells [ 146 , 147 ].…”

Section: Diagnosis Of Inborn Errors Of Thymic Stromal Cell Developmenmentioning

confidence: 99%

“…Novel tools are emerging to facilitate the distinction of primary haematopoietic defects from inborn errors of thymic stromal cells in patients presenting with genetically undefined severe T cell lymphopaenia [ 126 , 129 , 146 , 147 ]. These include the use of artificial thymic organoids that express DLL4 and can therefore support the differentiation of CD34 + haematopoietic stem cells (HSCs) into mature T cells [ 146 , 147 ]. In principle, HSCs from patients with thymic stromal cell defects should be able to generate mature T cells, whereas the T cell differentiation capacity of HSCs derived from patients with haematopoietic defects is generally expected to be impaired, although there may be exceptions as has been seen for adenosine deaminase deficiency [ 146 , 147 ].…”

Section: Diagnosis Of Inborn Errors Of Thymic Stromal Cell Developmenmentioning

confidence: 99%

Inborn errors of thymic stromal cell development and function

2020

View full text Add to dashboard Cite

As the primary site for T cell development, the thymus is responsible for the production and selection of a functional, yet self-tolerant T cell repertoire. This critically depends on thymic stromal cells, derived from the pharyngeal apparatus during embryogenesis. Thymic epithelial cells, mesenchymal and vascular elements together form the unique and highly specialised microenvironment required to support all aspects of thymopoiesis and T cell central tolerance induction. Although rare, inborn errors of thymic stromal cells constitute a clinically important group of conditions because their immunological consequences, which include autoimmune disease and T cell immunodeficiency, can be life-threatening if unrecognised and untreated. In this review, we describe the molecular and environmental aetiologies of the thymic stromal cell defects known to cause disease in humans, placing particular emphasis on those with a propensity to cause thymic hypoplasia or aplasia and consequently severe congenital immunodeficiency. We discuss the principles underpinning their diagnosis and management, including the use of novel tools to aid in their identification and strategies for curative treatment, principally transplantation of allogeneic thymus tissue.

show abstract

Diagnostic assay to assist clinical decisions for unclassified severe combined immune deficiency

Abstract: Key Points 3D organoid T-cell differentiation from a few hundred peripheral blood CD34+ cells was successfully achieved. 3D organoid T-cell differentiation could help physicians distinguish intrinsic from extrinsic defects underlying a clinical SCID phenotype.

Cited by 33 publications

References 9 publications

Artificial thymic organoids represent a reliable tool to study T-cell differentiation in patients with severe T-cell lymphopenia

Artificial thymic organoids represent a reliable tool to study T-cell differentiation in patients with severe T-cell lymphopenia

Current and Future Therapeutic Approaches for Thymic Stromal Cell Defects

Inborn errors of thymic stromal cell development and function

Contact Info

Product

Resources

About