Introduction

The selection of specific groups of cells is a widely used practice in both basic and applied biomedical science. The present invention relates to a process for inducing diphtheria toxin resistance in human cells, allowing their in vitro and in vivo selection.

Technical features

The selection of specific groups of human cells is typically carried out through stable transduction, i.e. permanent integration of exogenous genetic material in the cellular genome, capable of making cells resistant to specific cytotoxic antibiotics. The object of the present invention relates to a new selection method based on the resistance to diphtheria toxin instead of antibiotics. The method is based on the silencing of the DPH2 human gene, which codes for a key enzyme in the process that makes the human cell sensitive to diphtheria toxin, resulting in the conferment of resistance to this toxin and thus preventing cell death. Compared to the systems used today based on lethal drugs even for animal cells, since the diphtheria toxin binds the human but not the murine receptor, it kills human cells but not the murine ones and can therefore be used to select specific human cell populations in the mouse: indeed, it is sufficient to induce resistance to diphtheria toxin in the human cells of interest before transplanting them into the animal. Therefore, unlike traditional systems, the proposed selection method allows human cells to be selected both in vitro and in vivo. The possibility of select human cells in vivo is of particular interest for research on PDX models.

Possible Applications

• In vivo selection of human cells;
• Gene transduction;
• Functional and morphological studies in laboratory animals;
• Cancer studies;
• Preclinical test in PDX models (direct genetic manipulation of human tumor xenografts).

Advantages

• New resistance marker, very efficient and small in size;
• Allows in vivo selection with high performance;
• High-efficiency;
• High-stability;
• No toxicity.