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Increased constitutive interferon-β levels and altered CD4 T cell homeostasis induced by expression of a viral glycoprotein

ABSTRACT: Besides the strong type I interferon (IFN-I) response induced by infections, IFN-I is also produced constitutively at lower levels. Constitutive IFN-I production is often regulated by resident microbiota and is essential for induction of efficient immune responses. Here, we demonstrate in transgenic (tg) mice that expression of a single viral envelope gene, the glycoprotein (GP) of lymphocytic choriomeningitis virus (LCMV), increased constitutive IFN-β levels and induced numerous IFN-stimulated genes (ISGs). In addition, self-antigen-driven CD44highCD62Llow memory-phenotype and regulatory CD4 T cell populations were enlarged in these LCMV GP-tg mice but bona fide antigen-specific memory CD4 T cells were unchanged. In conclusion, our study shows that increased constitutive IFN-β levels induced by expression of a single viral envelope gene and accompanied by upregulated ISGs significantly altered CD4 T cell homeostasis. Furthermore, our data imply that a pathway capable of upregulating constitutive IFN-β levels can sense LCMV GP expression in vivo.

ORGANISM(S): Mus musculus

PROVIDER: GSE303494 | GEO | 2026/04/02

REPOSITORIES: GEO

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Increased constitutive interferon-β levels and altered CD4 T cell homeostasis induced by expression of a viral glycoprotein

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