Construction of a bacteriophage-derived vector with potential applications in targeted drug delivery and cell imaging

Abstract

There is a strong relation between dysregulation of epidermal growth factor receptor (EGFR) and the development of epithelial-derived cancers. Therefore, EGFR has usually been considered the desired target for gene therapy. Here, we propose an approach for targeting EGFR expressing cells by phage particles capable of displaying EGF and GFP as the tumor-targeting and reporting elements, respectively.For this, the superfolder GFP-EGF (sfGFP-EGF) coding sequence was inserted at the N-terminus of the pIII gene in pIT 2 phagemid. The capability of constructed phage to recognize EGFR overexpressing cells was monitored by uorescence microscopy, uorescence-activated cell sorting (FACS), and cell-based ELISA experiments. The FACS analysis showed a signi cant shift in the mean uorescence intensity (MFI) of the cells treated with phage displaying sfGFP-EGF compared to phage displaying only sfGFP. The binding of phage displaying sfGFP-EGF to A-431 cells, monitored by uorescence microscopy, indicated formation of sfGFP-EGF-EGFR complex on the surface of the treated cells. Cell-based ELISA experiments showed that the phages displaying either EGF or sfGFP-EGF can speci cally bind EGFR expressing cells.The vector constructed in the current study has the potential to be engineered for gene delivery purposes as well as cell-based imaging for tumor detection.