International scientists have made a simple cell scaffold from a virus. 

Zhongwei Niu and Qian Wang at the University of South Carolina, and colleagues in the US and China, developed the viral film which can be used to grow oriented arrays of cells.

The team based its scaffold on bacteriophage M13, a virus with an innate ability to organise into liquid crystals. Their aim was to study how well-ordered M13 films would affect cell behaviour. As cell behaviour is controlled by interactions between the cell and its surroundings, explain the researchers, scaffold patterning can influence cell responses. They point out that understanding these interactions is important in designing scaffolds for tissue engineering. 

To generate their scaffold, the researchers placed a suspension of M13 on a silane-coated glass slide. Slowly dragging the meniscus along the slide forced the virus to form a thin film exhibiting highly oriented M13 particles. The team then modified the film surface with tripeptides to enhance cell binding to the virus, and cultured mouse fibroblasts - cells typically found in connective tissue - on the film. They found that the cells were oriented and elongated along a single direction on the film.

'Designing biocompatible surfaces for cells has been a hot topic for many scientists,' says Wang. 'Virus-based substrates confer certain unique advantages. One, the structure of the virus is well-defined, therefore we can determine the position of our chemical or genetic modification, and the distance between each functional group. Two, the viruses can be organised into one- or two-dimensional structures. And lastly, viruses are protein-based materials, just like collagen and many other natural cell matrices. We hope to continue with our virus-based materials and their variations to study many cellular behaviours, such as bone formation, neuron regeneration and blood vessel repair.'

Jeff Capadona of Case Western Reserve University, Cleveland, and the L. Stokes Cleveland VA Medical Center, who currently researches smart biomimetic polymer nanocomposites, looks forward to the results of these further studies. 'The simplicity and elegance of cell orientation through the alignment of bacteriophages into thin films promises to become an important tool in probing cell function and behaviour,' he says.

Vikki Chapman