psiCRIP-MFG-S-TK1-67

**Semantic type:** Pharmacologic Substance

**Definition:** A gene transfer agent comprised of murine packaging cell lines, psiCRIP, and an engineered retroviral vector MFG-S containing the coding region of amino acid residues from 1-67 of HSV Thymidine Kinase which allows gene transfer to occur without viral replication in transduced cells and has been used as a selection marker with ganciclovir treatment.