GSM7070565
The primary human umbilical cord mesenchymal stem cells (UC-MSCs) were obtained from fetuses with natural labor in Central People's Hospital of Zhanjiang. The experiment has been approved by Institutional Ethics Committee of Central People's Hospital of Zhanjiang (IIT-2022-057-01). Briefly, the fresh umbilical cord was cut off into clumps and were digested with 1 g/L collagenase II for 1 h. The digested clumps were then cultured in DMEM supplemented with 20% fetal bovine serum (FBS, Gibco, 12800), 100 U/mL penicillin, and 100 U/mL streptomycin at 37°C under 5% CO2. After 16 days, the clumps were removed carefully and cells were serially passaged after reaching 80−90% confluence. Cells are qualified for microbiology and virology tests. The population doublings were calculated with PD = log2 (Ne/N0), where N0 represents the number of seeds and Ne represents the number of counts. Cumulative PD numbers represent the sum of PDs from all previous passages, with cells derived from the primary culture considered PD = 0. DNA libraries were constructed after 8 cycles of PCR amplification using the TruePrep DNA Library Prep Kit and sequenced on the Illumina Hiseq-PE150 platform to a depth of 4.0 × 107 reads.