Stable marker gene transfer into human bone marrow stromal cells and theirprogenitors using novel herpesvirus saimiri-based vectors

We have evaluated the ability of new herpesvirus saimiri (HVS)-based vector s to deliver a marker gene green fluorescent protein (GFP) into human bone marrow (BM) stromal cells and their progenitors. Stromal cells expanded fro m adherent layers of long-term BM cultures (LTC) were susceptible to HVS-ba sed infection in a dose-dependent manner, and the efficiency of 94.8 +/- 2. 0% was achieved using single exposure with HVS/EGFP vector at multiplicity of infection (moi) of similar to 50, Colony-forming unit-fibroblast (CFU-F) assay established the ability of HVS-based vectors to infect progenitors f or bone marrow stroma fibroblasts and transfer the marker gene over multipl e cell divisions in the absence of selective pressure. HVS was not toxic fo r stromal cells and progenitors and no viral replication was detected upon growth of modified stroma, On the basis these data, we believe that HVS-bas ed constructs can offer a new opportunity for selective gene delivery into bone marrow stromal cells and progenitors. The ability of HVS to infect nor adividing cells can be considered advantageous in the development of both e x vivo and in vivo strategies.