Three-dimensional spheroid culture of human umbilical cord mesenchymal stem cells promotes cell yield and stemness maintenance

Abstract

Mesenchymal stem cell (MSC) transplantation is a promising treatment of many diseases. However, conventional techniques with cells being cultured as a monolayer result in slow cell proliferation and insufficient yield to meet clinical demands. Three-dimensional (3D) culture systems are gaining attention with regard to recreating a complex microenvironment and to understanding the conditions experienced by cells. Our aim is to establish a novel 3D system for the culture of human umbilical cord MSCs (hUC-MSCs) within a real 3D microenvironment but with no digestion or passaging. Primary hUC-MSCs were isolated and grown in serum-free medium (SFM) on a suspension Rocker system. Cell characteristics including proliferation, phenotype and multipotency were recorded. The therapeutic effects of 3D-cultured hUC-MSCs on carbon tetrachloride (CCl4)-induced acute liver failure in mouse models were examined. In the 3D Rocker system, hUC-MSCs formed spheroids in SFM and maintained high viability and active proliferation. Compared with monolayer culture, the 3D-culture system yielded more hUC-MSCs cells within the same volume. The spheroids expressed higher levels of stem cell markers and displayed stronger multipotency. After transplantation into mouse, 3D hUC-MSCs significantly promoted the secretion of interferon-γ and interleukin-6 but inhibited that of tumor necrosis factor-α, thereby alleviating liver necrosis and promoting regeneration following CCl4 injury. The 3D culture of hUC-MSCs thus promotes cell yield and stemness maintenance and represents a promising strategy for hUC-MSCs expansion on an industrial scale with great potential for cell therapy and biotechnology.