Patent ID: 9133263
Filing Date: 2015-09-15
Classification: C07K,C12N

Abstract:
1. A cultured mammalian cell containing a gene encoding a conditionally expressed transgenic extracellular surface marker that is detectable on the surface of the cell and exhibits one or both of resistance to digestion with trypsin and non-internalization by the cell upon binding of an antibody, wherein the gene encoding a conditionally expressed transgenic surface marker comprises: (i) a promoter for driving the transcription of a first transcription sequence, operably linked to (ii) a said first transcription sequence for preventing transcription of a second transcription sequence, thereby avoiding an immune response against the cell, wherein the first transcription sequence is conditionally removable by a CRE recombinase or a FLP recombinase, and (iii) a said second transcription sequence encoding the extracellular surface marker, comprising whereby the first transcription sequence is conditionally removable such that the second transcription sequence is transcribable, and whereby the surface marker renders the cell sortable through the detection of the conditionally expressed transgenic surface marker on the extracellular surface of the cell.