Protection of CD4+ T cells from hepatitis C virus infection-associated senescence via ΔNp63–miR-181a–Sirt1 pathway

Y Zhou, GY Li, JP Ren, L Wang, J Zhao… - Journal of Leucocyte …, 2016 - academic.oup.com
Y Zhou, GY Li, JP Ren, L Wang, J Zhao, SB Ning, Y Zhang, JQ Lian, CX Huang, ZS Jia…
Journal of Leucocyte Biology, 2016academic.oup.com
T cell dysfunction has a crucial role in establishing and maintaining viral persistence. We
have previously shown a decline in miR-181a, which regulates CD4+ T cell responses via
DUSP6 overexpression, in individuals with hepatitis C virus (HCV) infection. Here, we
describe accelerated T cell senescence in HCV-infected individuals compared with age-and
sex-matched healthy subjects. Mechanistic studies revealed that up-regulation of
transcription factor ΔNp63 led to the decline of miR-181a expression, resulting in an …
Abstract
T cell dysfunction has a crucial role in establishing and maintaining viral persistence. We have previously shown a decline in miR-181a, which regulates CD4+ T cell responses via DUSP6 overexpression, in individuals with hepatitis C virus (HCV) infection. Here, we describe accelerated T cell senescence in HCV-infected individuals compared with age- and sex-matched healthy subjects. Mechanistic studies revealed that up-regulation of transcription factor ΔNp63 led to the decline of miR-181a expression, resulting in an overexpression of the antiaging protein Sirt1, in CD4+ T cells from HCV-infected individuals. Either reconstituting miR-181a or silencing ΔNp63 or Sirt1 expression in CD4+ T cells led to accelerated T cell senescence, as evidenced by an increased senescence-associated β-galactosidase (SA-β-gal) expression, shortened telomere length, and decreased EdU incorporation; this suggests that HCV-induced T cell senescence is counterregulated by the ΔNp63–miR-181a–Sirt1 pathway. An increase of IL-2 production was observed in these senescent CD4+ T cells and was driven by a markedly reduced frequency of Foxp3+ regulatory T (Treg) cells and increased number of Foxp3 effector T (Teff) cells upon manipulating the ΔNp63–miR-181a–Sirt1 pathway. In conclusion, these findings provide novel mechanistic insights into how HCV uses cellular senescent pathways to regulate T cell functions, revealing new targets for rejuvenating impaired T cell responses during chronic viral infection.
Oxford University Press