Purpose - Bone marrow aspirate concentrate (BMAC) has been used at our centre as a cost-effective biological treatment for ankle cartilage repair procedures. Mesenchymal stromal cells (MSCs) are proposed to give BMAC its restorative properties. There are numerous methods of obtaining and concentrating bone marrow aspirate (BMA), and each method may alter the quantity and quality of MSCs in the final product. Here, we characterise the MSCs obtained from BMAC generated by one such commercial kit- complete cartilage regeneration (CCR), marketed by RegenGlobal.
Methods and materials - BMAC obtained via the CCR kit during surgeries for patients with osteochondral lesions of the talus (OLTs) (n=10, aged 44±24 (Med±IQR), 6 female, 4 male) were directly plated on T25 flasks with 5ml complete media. After 24 hours adherence, cell culture flasks were washed with PBS and refreshed with complete media. Adherent cells were passaged after reaching up to 80% confluency and immunoprofiling (n=5) were performed.
Results - BMAC samples from patients aged ≤40 (n=5, 3 female, 2 male) produced MSC colonies when plated, while BMAC from patients >40 (n=5, 3 female, 2 male), did not give rise to stably proliferating MSCs. All samples (n=5) at passages 0, 1 or 2 did not adhere to the MSC ISCT criteria for positive markers CD73 (n=4, 87.2±7.9), CD90 (n=2, 75.8±14.6), CD105 (n=2, 85.8±0.42) and negative marker CD14 (n=3, 27.7±16.5). All data are Mean±SD.
Conclusion - These preliminary investigations indicate that patient age may change the quantity and quality of BMAC obtained. Moreover, there is a need to better assess the quality of the BMA used in these procedures, as well as better characterisation of both MSCs derived from BMAC and the other constituents of the BMAC product. Further investigation is needed as to how the MSCs behave when mixed with fibrin and hyaluronan scaffold, as is performed in this surgical technique.