Transitional B cells in quiescent SLE: An early checkpoint imprinted by IFN.
J Autoimmun
; 102: 150-158, 2019 08.
Article
en En
| MEDLINE
| ID: mdl-31085070
ABSTRACT
Systemic lupus (SLE) is characterized by a break of B cell tolerance that plays a central role in disease pathophysiology. An early checkpoint defect occurs at the transitional stage leading to the survival of autoreactive B cells and consequently the production of pathogenic autoantibodies. The main purpose of our work was to determine whether transitional B cells, as the most immature naïve B cell subset upstream of pathogenic B cells, display specific features compared to healthy non SLE subjects. Through extensive analysis of transitional B cells from untreated or low treated, mostly Caucasian, SLE patients, we demonstrated that transitional (T1 and T2) B cell frequencies were increased in SLE and positively correlated with disease activity. SLE transitional B cells displayed defects in two closely inter-related molecules (i.e. TLR9 defective responses and CD19 downregulation). RNA sequencing of sorted transitional B cells from untreated patients revealed a predominant overexpression of interferon stimulated genes (ISGs) even out of flares. In addition, early transitional B cells from the bone marrow displayed the highest interferon score, reflecting a B cell interferon burden of central origin. Hence, the IFN signature in transitional B cells is not confined to African American SLE patients and exists in quiescent disease since the medullary stage. These results suggest that in SLE these 3 factors (i.e. IFN imprintment, CD19 downregulation and TLR9 responses impairment) could take part at the early transitional B cell stage in B cell tolerance by-pass, ultimately leading in periphery to the expansion of autoantibodies-secreting cells.
Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Interferones
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Antígenos CD19
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Receptor Toll-Like 9
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Células Precursoras de Linfocitos B
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Lupus Eritematoso Sistémico
Límite:
Adult
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Aged
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Female
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Humans
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Middle aged
Idioma:
En
Año:
2019
Tipo del documento:
Article