Abstract

Real-time monitoring of specific oxygen uptake rates of embryonic stem cells in a microfluidic cell culture device

Nicolas Szita, Professor, University College London

The cellular microenvironment determines the survival, proliferation and phenotype of the cells. Factors that influence the microenvironment include physicochemical (pH, dissolved oxygen concentration, hydrodynamic shear stress and temperature), and biochemical parameters (concentration of nutrients, metabolites and growth factors). Among these factors, dissolved oxygen (DO) is of specific interest in stem cell biology; it is not only sustaining cell metabolism, but crucially it acts as a signaling molecule to determine cell fate and potential differentiation to different lineages. Under low levels of oxygen, spontaneous differentiation, inhibition of self-renewal, differentiation into cardiomyocytes, hematopoietic cells, photoreceptors, and even increasing neural commitment of mouse embryonic stem cells (mESCs) has been reported. Precise and robust monitoring and control strategies of the DO in the culture medium is required to further clarify the exact impact of oxygen concentration levels on cellular fate. In this contribution we present a microfluidic device capable of finely controlling the microenvironment and monitoring the oxygen tension levels. Also, we demonstrate for the first time the real-time measurement of specific oxygen uptake rate without disrupting the stem cell culture.