Recombinant [lambda] Bacteriophage Displaying Nanobody towards Third Domain of HER-2 Epitope Inhibits Proliferation of Breast Carcinoma SKBR-3 Cell Line

Phage display of many nanobodies via filamentous phage in combination with helper phage has been reported by many scientists. The aim of this study was to produce lambda ([lambda]) bacteriophage displaying high-affinity nanobody against HER-2 expressing breast carcinoma cells. Bacteriophage [lambda] is a temperate phage with inherent biological safety in mammalian cells. Here we report the construction of a recombinant [lambda] phage that efficiently expresses specific nanobody towards third domain of HER-2 target on SKBR-3 and MCF-7 cell lines in vitro. We constructed recombinant [lambda] phage particles containing a mammalian expression cassette, C-Myc tagged, encoding VHH gene of camelid anti HER-2 third domain epitope using [lambda] ZAP-cytomegalic virus (CMV) vector. The SKBR-3, MCF-7 and human endometrial stem cells were treated by the nanobody displayed recombinant [lambda] phage. The cell growth inhibition assay was performed by MTT Cell Viability Assay Kit. After the fourth round of biopanning there was a significant enrichment in the phage specifically binding to the antigen. The ratio of targeted phage increased approximately 1,000-fold in the fifth round. The nanobody expressed by [lambda] ZAP-CMV-VHH phagemid cloned in [lambda] bioparticles significantly inhibited the proliferation of HER-2 positive SKBR-3 and MCF-7 cells. Recombinant bacteriophage [lambda] ZAP-CMV-VHH-cDNA could be used efficiently for construction of nanobodies to mortify HER-2 positive breast carcinoma cells as a nanomedical therapeutic.[PUBLICATION ABSTRACT]