Research using hematopoietic cells and other suspension cells has been limited in part by low efficiency of gene transfer (transduction and transfection) into these cell types. RetroNectin reagent promotes co-localization of lentivirus or retrovirus with target cells to dramatically enhance transduction efficiency. As a consequence, RetroNectin reagent is now the gold standard transduction enhancer for retroviral/lentiviral gene transfer to hematopoietic cells and holds great promise in clinical application, having been used in over 40 clinical trials.
What is RetroNectin?
RetroNectin reagent is a recombinant human fibronectin fragment (rFN-CH-296) that contains three functional domains: the cell-binding domain, the heparin-binding domain, and the CS-1 sequence.
How does RetroNectin work?
RetroNectin enhances lentiviral- and retroviral-mediated gene transduction by aiding the co-localization of target cells and viral particles. Specifically, virus particles bind RetroNectin reagent via interaction with the H-domain, and target cells bind mainly through the interaction of cell surface integrin receptor VLA-5 and VLA-4 with the fibronectin C-domain and CS-1 site, respectively. By facilitating close physical proximity, RetroNectin reagent can enhance viral-mediated gene transfer to target cells expressing integrin receptors VLA-4 and/or VLA-5. VL-4-expressing cells include T cells, B cells, monocytes, NK cells, eosinophils, bone marrow monocytic cells, and lymphoid progenitors. Thymocytes, activated T-cells, and mast cell express VLA-5.
RetroNectin reagent also can be used to enhance T cell expansion in vitro.
T lymphocyte expansion from peripheral blood mononuclear cells (PBMCs) is usually performed in the presence of interleukin-2 (IL-2) and anti-CD3 antibody stimulation. The efficiency of T cell expansion can be significantly increased in the presence of RetroNectin reagent. Moreover, the T cell population after expansion in the presence of RetroNectin reagent contains a high proportion of naive T cells.
