(730b) Investigating the Interaction Between Virus Vectors and Adhesive Proteins for Substrate-Mediated Gene Delivery

Complex tissue development requires precise control over the spatial organization of gene expression. We have developed a platform to allow for both viral gene delivery vectors and adhesive proteins to be co-patterned to control both cellular attachment and gene expression. Our approach, based on adeno-associated virus (AAV), should enable tissue engineers to obtain specific, spatially organized expression of genes in a population of cells. Polydimethylsiloxane (PDMS) stamps were first used to micropattern protein-adhesive alkanethiols onto gold-coated substrates. Incubation of the self-assembled monolayers (SAMs) with extracellular matrix (ECM) proteins and AAV resulted in co-patterning of cell-adhesive proteins and gene delivery vectors. We have previously observed a synergistic effect between the patterning of human fibronectin (HFN) and AAV for the delivery of genes to HeLa cells.  Here, we further explore this technology by examining additional adhesive proteins and demonstrate that collagen I, elastin, laminin, and poly-l-lysine are also compatible with our platform. Cell adhesion and gene expression were monitored over three days and while all proteins and surfaces tested were successful, we observe that laminin pre-adsorption yields the highest gene delivery efficiency. BrU incorporation tests indicate this increase in gene expression is not due to increased HeLa cell transcriptional activity when seeded on laminin surfaces.  Quantitative analysis of AAV binding/dissociation kinetics from various ECM surfaces may shed light on why laminin is able to mediate the most effective gene delivery. Therefore, quartz crystal microbalance (QCM) and surface plasmon resonance (SPR) were used to investigate the interaction between AAV and these adhesive proteins.  By combining microcontact printing with viral gene delivery vectors, we have successfully patterned both cell adhesion and gene expression.