Multiparametric senescent cell phenotyping reveals CD24 osteolineage cells as targets of senolytic therapy in the aged murine skeleton

  • bioRxiv. 2023 Jan 13:2023.01.12.523760. doi: 10.1101/2023.01.12.523760.
Madison L Doolittle  1  2 ,  Dominik Saul  1  2  3 ,  Japneet Kaur  1  2 ,  Jennifer L Rowsey  1  2 ,  Stephanie J Vos  1  2 ,  Kevin D Pavelko  4 ,  Joshua N Farr  1  2 ,  David G Monroe  1  2 ,  Sundeep Khosla  1  2
Affiliations
  • 1. Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic, Rochester, MN, 55905, USA.
  • 2. Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN 55905, USA.
  • 3. Department for Trauma and Reconstructive Surgery, BG Clinic, University of Tübingen, Germany.
  • 4. Department of Immunology, Mayo Clinic, Rochester, MN, 55905, USA.
PMID: 36711531 DOI: 10.1101/2023.01.12.523760
Abstract

Senescence drives organismal aging, yet the deep characterization of senescent cells in vivo remains incomplete. Here, we applied mass cytometry by time-of-flight (CyTOF) using carefully validated antibodies to analyze senescent cells at single-cell resolution. We used multiple criteria to identify senescent mesenchymal cells that were growth arrested and resistant to Apoptosis (p16+/Ki67-/BCL-2+; "p16KB" cells). These cells were highly enriched for senescence-associated secretory phenotype (SASP) and DNA damage markers and were strongly associated with age. p16KB cell percentages were also increased in CD24+ osteolineage cells, which exhibited an inflammatory SASP in aged mice and were robustly cleared by both genetic and pharmacologic senolytic therapies. Following isolation, CD24+ skeletal cells exhibited growth arrest, SA-βgal positivity, and impaired osteogenesis in vitro . These studies thus provide a new approach using multiplexed protein profiling by CyTOF to define senescent mesenchymal cells in vivo and identify a highly inflammatory, senescent CD24+ osteolineage population cleared by senolytics.

Products