Successful scale up expansion of Wharton's jelly mesenchymal stromal cells in different commercial xeno-free and serum-free media

Abstract

Background & Aim Cell-based therapies are becoming widely accepted in regenerative medicine and their demand and potential is increasing. Human multipotent Mesenchymal Stromal Cells (MSC) derived from the Wharton's jelly (WJ) of the umbilical cords can be obtained from samples typically discarded from public cord blood banking programmes. However, current cell culture bioprocesses for the derivation, scale up expansion, and GMP-compliant product manufacturing for early phase clinical trials use serum and xenogeneic proteins in medium formulation. Therefore, the use of xeno-free and serum-free media (XSFM) formulations is required to ensure more homogenous cell populations. The aim of this study was to compare four commercially available XSFM as an alternative to human serum-containing media in WJ-MSC culture. Methods, Results & Conclusion Cryopreserved MSC derived from WJ in serum-conditions were cultured in four commercial XSFM, namely PRIME-XV MSC Expansion XSFM, MSC Nutristem® XF, MesenCult™-ACF Plus Medium, and MSC-Brew GMP Medium and were further compared with conventional expansion medium Dulbecco's modified Eagle's medium (DMEM) containing 2 mM glutamine and supplemented with 10% of human serum B (hSerB). Cells were successfully expanded in culture in all XSFM conditions. Cumulative population doublings and harvest cell densities were higher in early passages for 3 out of 4 XSFM than serum-containing expansion medium. WJ-MSC proliferation was higher than 1 × 105 cells/cm2 in early culture (passage 2) while it decreased under 1 × 105 cells/cm2 in late culture (passage 8) in XSFM conditions. Spindle shaped morphology was kept upon passages in XSFM conditions. In all cases, cells were highly positive for CD73, CD90 and CD105 and negative for CD31, CD45 and HLA-DR expression in passage 1 and 6 and multilineage capacity to osteogenic, adipogenic and chondrogenic lineages was confirmed after in vitro induction. These data demonstrate that WJ-MSC can be successfully cultured and expanded in commercially available xeno-free and serum-free media and retain all necessary characteristics attributed to MSC for potential therapeutic use.