RETROVIRAL-MEDIATED GENE-TRANSFER INTO HUMAN BONE-MARROW STROMAL CELLS - STUDIES OF EFFICIENCY AND IN-VIVO SURVIVAL IN SCID MICE

Retroviral-mediated gene transfer into bone marrow cells is extensivel y used in gene therapy protocols. Cytokines are needed for stimulation , to achieve a high rate of gene transfer. However, the stromal cell c ompartment of bone marrow is characterized by rapid proliferation even without cytokines. In this study, human bone marrow stromal cells wer e isolated and subsequently infected with recombinant retrovirus in a cell-free supernatant. The LN retroviral vector used in this study car ries the bacterial neomycin phosphotransferase gene (neoR). Transducti on efficiency was significantly enhanced by repeated cycles of infecti on, with a maximum of 98% transduced cells by four rounds of infection . Presence of the neoR-gene was detected by PCR from all stromal cells selected by G418 After culture in vitro for 3 months, cells were stil l positive for PCR amplification of the neoR-gene. Transduced stromal cells were also injected into SCID mice to study their homing and surv ival ability in vivo.