Femur bone marrow from brain death deceased donors as source of human mesenchymal stromal cells for cell therapy.

Background: The use of a deceased donor (DD) as an alternative source of human mesenchymal stromal cells (hMSC) is promising, but has been little explored. This study evaluated the potential of femur bone marrow (FBM) from brain-death donors as a source of hMSC and compared this with hMSC from matched iliac crest bone marrow (ICBM).

Methods: Sixteen donor-matched FBM and ICBM samples were processed from brain-death donors. We analyzed the starting material and compared cell yield, phenotypic profile and differentiation capacity of hMSC.

Results: Neither the amount of nucleated cells per gram (14.6×10⁶±10.3×10⁶ from FBM vs. 38.8×10⁶±34.6×10⁶ from ICBM, P≥0.09) nor the frequency of CFU-F (0.0042%±0.0036% in FBM vs. 0.0057%±0.0042% in ICBM, P≥0.73) differ significantly from FBM or ICBM. Cell cultures from both sources were obtained and hMSC yields showed that there were no significant differences in hMSC obtained per gram of bone marrow (BM) when comparing femur with iliac crest samples. At passage 2, 12.5×10⁶±12.9×10⁶ and 5.0×10⁶±4.4×10⁶ hMSC per gram of BM were obtained from FBM and ICBM, respectively. FBM and ICBM hMSC express CD73, CD90, CD105, but not hematopoietic lineage markers [CD45, CD34, CD11, CD19 and isotype of HLA clase II (HLA-DR)]. HLA-A expression from both sources was clearly detected, while HLA-B was weakly expressed or undetectable and HLA-DR was undetectable. Cells from both sources were differentiated in vitro into osteoblasts, adipocytes and chondroblasts.

Conclusions: To our knowledge, there are no previous studies evaluating BM from femur dead donors as a source of hMSC. Our findings confirm that it is feasible to expand cells from FBM from brain-death donors meeting in vitro characteristics of hMSC, making them a promising source for clinical translation.