Improved Recombinant Retroviral Titers Utilizing Trichostatin A
Recombinant retroviruses are a common vehicle to deliver an exogenous gene to a target cell, which makes them a useful tool in the field of gene therapy. A major drawback to using recombinant retroviruses is the low titer achieved, resulting in a limited number of target cells infected and subsequently poor expression of a transgene. In this study, we created an ecotropic producer cell line that contained recombinant mouse nerve growth factor (NGF) and the reporter gene LacZ . This cell line,
... . This cell line, termed y 2 /LIG/ NGF, was treated with the drug trichostatin A, an inhibitor of histone deacetylase. At a concentration of 3 mM trichostatin A, the retroviral titer of this producer cell line was increased 34-fold relative to untreated control cells and 3.4-fold compared to the commonly used hyperacetylating compound sodium butyrate. Producer cells treated with trichostatin A also increased the number of primary rat marrow stromal cells infected 5.8-fold compared to untreated producer cells. These results offer a simple and effective solution for converting low titer producer cell clones to higher titer clones, which can be easily tested and applied. Figure 5. Photomicrographs of representative b-gal staining of NIH 3T3 cells after trichostatin A, sodium butyrate or control treatments under 100 magnification. Note the largest increase in b-gal-positive cells with 3 mM trichostatin A.