Healthy donors
In the study, a total of 45 healthy adult individuals who routinely
received BM examination as allo-HSCT donors from July 1, 2020 to March
1, 2021 at Peking University Institute of Hematology were enrolled.
Donors aged <30 years, 30-45 years, and >45 years
were
divided
into the young, middle-aged and old groups respectively, with 15 donors
per group. The donor characteristics, including age, sex, and routine
peripheral blood parameters were evaluated among young, middle-aged and
old donors.
Peking University People’s Hospital Ethics Committee consented the
study. Moreover, all subjects signed informed consent before
enrollment,
in conformity to the Declaration of Helsinki.
Characterization
of BM ECs
BM mononuclear cells (BMMNCs) were isolated with Ficoll-Paque solution
(HaoYang, Tianjin, China). The following multicolour flow cytometry
panel were applied to quantify ECs in BM: anti-CD34-PE/Cy7,
anti-CD309-PE, and anti-CD133-APC (BD Biosciences, CA, USA). ECs were
identified as
CD34+CD309+CD133+,
and the relative EC frequency was expressed as a fraction of
BMMNCs[23-27]. Samples were collected on a BD LSRFortessa flow
cytometer and the compensation adjustion as well as data analysis were
accomplished via a BD LSRFortessa software.