A cost-effective method to enhance adenoviral transduction of primary murine osteoblasts and bone marrow stromal cells

Abstract

We report here a method for the use of poly-l-lysine (PLL) to markedly improve the adenoviral transduction efficiency of primary murine osteoblasts and bone marrow stromal cells (BMSCs) in culture and in situ, which are typically difficult to transduce. We show by fluorescence microscopy and flow cytometry that the addition of PLL to the viral-containing medium significantly increases the number of green fluorescence protein (GFP)-positive osteoblasts and BMSCs transduced with an enhanced GFP-expressing adenovirus. We also demonstrate that PLL can greatly enhance the adenoviral transduction of osteoblasts and osteocytes in situ in ex vivo tibia and calvaria, as well as in long bone fragments. In addition, we validate that PLL can improve routine adenoviral transduction studies by permitting the use of low multiplicities of infection to obtain the desired biologic effect. Ultimately, the use of PLL to facilitate adenoviral gene transfer in osteogenic cells can provide a cost-effective means of performing efficient gene transfer studies in the context of bone research.

Genetics: Improved gene delivery boosts bone research

Gene delivery to bone cells has been improved by use of a common compound, potentially making bone research cheaper and more efficient. Delivery of genes to cultured bone and bone marrow cells can be used to study the effects of specific genes in bone development and disease, but the standard technique of delivering genes using adenovirus is inefficient. Joseph Stains from the University of Maryland School of Medicine and colleagues have shown that the technique can be improved by adding poly-L-lysine with the adenovirus. Poly-L-lysine increased the percentage of cells that genes were delivered to, and increased the efficiency of delivery to each cell. The technique provides a simple way to increase the efficiency of genetic experiments in bone cells and consequently reduce their cost.

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