Abstract

Engineered Bacteria to Control Stem Cell Behaviour

Manuel Salmeron-Sanchez, Professor of Biomedical Engineering, University Of Glasgow

The extracellular matrix (ECM) provides mechanical and biochemical support to cells, and plays a critical role in cell behaviour. Our aim is to engineer novel interfaces that mimic the dynamic behavior of the extracellular matrix, in particular in terms of integrin/receptor interactions as well as the presentation of growth factors. To do that, we have engineered biointerfaces between synthetic materials and cells that consist of genetically modified non-pathogenic Lactococcus lactis. This layer of bacteria constitutes a functional and dynamic interface that can be tuned to express adhesion proteins and growth factors, which constitutes an advanced and revolutionary way to control cell behavior in general and stem cell differentiation in particular. Bacteria were successfully modified and characterized to assess both the expression of FNIII1-10 as a membrane bound protein as well as the expression and secretion of BMP-2. Then, stem cell adhesion was studied on the engineered biointerfaces, and the formation of focal adhesions was quantified on the living interfaces. We show that the presence of BMP-2 induces stem cell differentiation towards osteogenic lineages on a layer of engineered L. lactis.