Pooling of Human Bone Marrow Mesenchymal Stromal Cells from different Donors demonstrate Distinctive Advantage than Single Donor MSCs

Abstract

Abstract Mesenchymal stromal cells (MSC) from adult bone marrow is most commonly used cells in clinical trials. MSCs from single donors are the preferred starting material but suffer from a major setback of being heterogeneous among donors that results in an unpredictable and inconsistent clinical outcomes. To overcome this, we developed a method of pooling MSCs from different donors and created cell banks to cater clinical needs. Initially, the master cells banks (MCBs) were created at passage 1 (P1) from the bone marrow MSCs isolated from of nine different donors. At this stage, MCBs from three different donors were mixed in equal proportion and expanded till P3 to create working cell banks (WCBs). Further, the pooled cells and individual donor MSCs were expanded till P5 and cryopreserved and were extensively characterised. The results showed that there was a huge heterogeneity among the individual donor MSCs in terms of growth kinetics, immunosuppressive ability and the level of angiogenic factors secretion potential. Comparatively, the pooled cells have more stable profiles and exhibit better immunosuppressive ability and consistent secretion of angiogenic factors. Further pooling doesn’t compromise the trilineage differentiation capacity or phenotypic marker expression of the MSCs. The senescence and in vitro tumourigenicity characteristics of the pooled cells are also similar to that of individual donor MSCs. We conclude that Pooling of MSCs from three different donors reduces heterogeneity among individual donors and produce MSCs with a consistent secretion and higher immunosuppressive profiles.