Gene transfer to tumor-infiltrating lymphocytes and other mammalian somatic cells by microprojectile bombardment.

We demonstrate the application of particle delivery to the transformation of mammalian somatic cells. Two mouse T-lymphocyte cell lines and Chinese hamster ovary (CHO) cells were transformed transiently with the RSV-ADH (alcohol dehydrogenase) gene. Stable gene transfer was also demonstrated in CHO cells at a frequency of 6 x 10(-4) and in T-cells at a frequency of 1 x 10(-4), using beta-Gal/neomycin-resistance gene constructs. The helium gas acceleration mechanism (PDS 1000/He) and particle delivery method allowed better velocity control and particle dispersion than the gunpowder driven instrument. These improvements have increased cell viability, transformation efficiency, and cellular targets.