XStamp cloning and expression lentivector MSCV-Leader-MCS-C1C2-EF1-Puro

Product Description

Engineer tissue-specific exosomes—clone-in your own targeting ligand for customized specificity using the XStamp cloning and expression lentivector

XStamp is based upon a C-terminal fusion of the C1C2 domain from the protein MFG-E8, which is targeted to the exosome surface. Protein sequences that are fused to the XStamp tag will efficiently display the protein ligand fusion on the surfaces of secreted exosomes.

To target your protein ligand to the exosome surface, simply clone the gene encoding your protein ligand-of-interest into the MCS site of the XStamp Cloning and Expression Vector. Your ligand will have a 5’ secretion signal sequence and a C-term XStamp. The XStamp Lentivector also features a downstream EF1-Puromycin cassette for positive selection and, when packaged into virus, the XStamp Lentivector can be used to create stable cell lines that secrete your engineered exosomes.

In addition to the XStamp Cloning and Expression Lentivector, SBI also offers a selection of pre-built targeting XStamp Lentivectors, see table Related Products below.

XStamp Targeting in Action

Figure 1. XStamp with motilin specifically targets exosomes to GI cells. Motilin is a 22-amino acid polypeptide hormone that binds to the motilin receptor, which is exclusively expressed in the intestine. XStamp with motilin can be used to target exosomes to GI cells. METHODS: The XStamp-Motilin construct (Cat.# XSTP720PA-1) was transfected into HEK293 cells and after 48 hours, the exosomes were isoalted using ExoQuick-TC. The next day, the XStamp-Motilin exosomes were Exo-Fected with a Texas-Red-labeled siRNA to monitor exosome docking and delivery. The transfected XStamp-Motilin exosomes were then added to MDA-MB-231 Breast Cancer Cells (motilin receptor negative) and to HT-29 Colon Cancer Cells (motilin receptor positive). The cells were imaged after 24 hours for uptake of the Texas-Red-labeled siRNA delivery from the XStamped exosomes. The HT-29 colon cancer cells that are motilin receptor positive took up the XStamp-Motilin exosomes at a much higher rate than the MDA-MB-231 Breast Cancer (motilin receptor negative) cells.