Rapid expansion of mesenchymal stem/stromal cells using optimized media supplemented with human platelet lysate PLTMax® or PLTGold®, suitable for cGMP expansion at large scale.

Abstract

Background & Aim Mesenchymal Stem/Stromal Cells (MSCs) are a promising candidate for tissue engineering and regenerative medicine applications due to their capacity of self-renewal and multilineage differentiation, ease of isolation and ability to grow in vitro. They are currently being used in hundreds of clinical trials and have been safely administered to thousands of patients with an expanding body of evidence of therapeutic efficacy. Mill Creek Life Sciences’ PLTMax®, derived from normal human donor platelets, arose as an alternative to FBS to be used as a supplement for in vitro expansion of human cells used in clinical applications. It is the only media supplement to date demonstrating clinical cultures of MSCs with long term genetic fidelity, rapid expansion and potent clinical activity. PLTMax® is being used worldwide in over 30 clinical trials including Phase I, II and III. Our latest product PLTGold®, is a second-generation human platelet lysate that does not require the addition of heparin to remain clot free, thus providing a fully xenogeneic free alternative supplement. Methods, Results & Conclusion In traditional monolayer expansion systems, we have demonstrated growth of adipose derived and bone marrow derived MSCs using an optimized, fully cGMP compliant culture system. We have found that MSC NutriStem® XF Basal Medium (Biological Industries USA, Inc, Cromwell, CT) supplemented with PLTMax® or PLTGold® exceeds the performance of other conventional media products, obtaining up to 5 × 108 cells in only 5 passages (5 times more cells than with other commercially available products). Furthermore, when we use MSC NutriStem® XF Complete Medium supplemented with PLTMax® or PLTGold®, we obtained up to 2 × 1010 cells in only 5 passages (200 times more cells than with other commercially available products). Cells grown in these media maintained MSC phenotype and capacity to undergo differentiation. The effective transfer into the clinic of allogeneic cell therapies using MSCs will depend predominantly on the development of large scale and cost effective manufacturing platforms that allow production of functional cells at the scale required to meet clinical demand. We also present the extension of these studies using this optimized method to evaluate 9 different microcarriers. Together, we will present an optimized protocol for the establishment of large scale expansion of MSCs in bioreactors.