Identity, proliferation capacity, genomic stability and novel senescence markers of mesenchymal stem cells isolated from low volume of human bone marrow (II)

Human bone marrow mesenchymal stem cells (hBM-MSCs) hold promise for treating diseases for which currently no therapeutic options exist. High quantities of MSCs are needed, requiring extensive cell expansion in long-term culture. However, the fundamental biological properties of MSCs can be altered by culture conditions. In this study, hBM-MSCs were isolated from residual human bone marrow (hBM) material and expanded to clinically relevant numbers at passage 3-4. The cells had normal morphology, proliferation rate, immunophenotype and karyotype. Despite the chromosomal stability, after additional three passages (P6-P7) hBM-MSCs entered senescence state, confirmed by SA-β-galactosidase staining and paralleling the slower proliferation, altered morphology and imunophenotype. qRT-PCR array profiling revealed 10 out of 86 genes significantly (p <0.05) differentially (≥2 fold) expressed in the late passage cells compared to the early passage cells qPCR gene expression profiling. hBM-MSCs from 3 (1 male and 2 females) adult donors (age 30±7.21 years) were used. Each sample was tested in technical duplicate. 6 samples of early passage (P3-P4) hBM-MSCs were grouped to CONTROL group and 6 samples of late passage (P6-P7) hBM-MSCs were grouped to TEST group. The data were analyzed using web-based RT2 Profiler PCR Array Data Analysis v3.5 software (Qiagen)