Continuous mitotic activity of primitive hematopoietic stem cells in adult mice.
J Exp Med
; 217(6)2020 06 01.
Article
em En
| MEDLINE
| ID: mdl-32302400
ABSTRACT
The proliferative activity of aging hematopoietic stem cells (HSCs) is controversially discussed. Inducible fluorescent histone 2B fusion protein (H2B-FP) transgenic mice are important tools for tracking the mitotic history of murine HSCs in label dilution experiments. A recent study proposed that primitive HSCs symmetrically divide only four times to then enter permanent quiescence. We observed that background fluorescence due to leaky H2B-FP expression, occurring in all H2B-FP transgenes independent of label induction, accumulated with age in HSCs with high repopulation potential. We argue that this background had been misinterpreted as stable retention of induced label. We found cell division-independent half-lives of H2B-FPs to be short, which had led to overestimation of HSC divisional activity. Our data do not support abrupt entry of HSCs into permanent quiescence or sudden loss of regeneration potential after four divisions, but show that primitive HSCs of adult mice continue to cycle rarely.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Envelhecimento
/
Células-Tronco Hematopoéticas
/
Mitose
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
J Exp Med
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Alemanha