Polymer scaffolds let plant cells twist and weave

Miniscule artificial scaffolding units made from nano-fiber polymers and built to house plant cells have enabled scientists to see for the first time how individual plant cells behave and interact with each other in a three-dimensional (3D) environment.

These ‘hotels for cells’ mimic the extracellular matrix that cells secrete before they grow and divide to create plant tissue. In this environment, scientists can observe and image individual plant cells developing in a more natural, multi-dimensional environment than previous 'flat' cell cultures. The research, conducted by a team of scientists from Cambridge University's Sainsbury Laboratory and Department of Materials Science & Metallurgy, is published in the open access journal BMC Plant Biology.

While similar 'nano-scaffold' technology has long been used for mammalian cells, resulting in advances in tissue engineering research, this is the first time such technology has been used for plant cells. "Until now, nobody had tried to put plant cells in an artificial fiber scaffold that replicates their natural environment and tried to observe their interactions with one or two other cells, or fiber itself," said plant scientist and co-author Raymond Wightman.

Co-author and material scientist Stoyan Smoukov suggests that a possible reason why artificial scaffolding on plant cells had never been done before was the expense of 3D nano-fiber matrices (the high costs have previously been justified in mammalian cell research due to its human medical potential).

However, Smoukov has co-discovered and recently helped commercialize a new method for producing polymer fibers for 3-D scaffolds inexpensively and in bulk. 'Shear-spinning' produces masses of fiber, in a technique similar to creating candy-floss but at the nanoscale. The researchers were able to adapt such scaffolds for use with plant cells.

This approach was combined with electron microscopy imaging technology. In fact, using time-lapse photography, the researchers have even managed to capture 4-D footage of these previously unseen cellular structures. "Such high-resolution moving images allowed us to follow internal processes in the cells as they develop into tissues," said Smoukov, who is also using the methods in this plant study to research mammalian cancer cells.

The scientists were able to see individual plant cells clinging to and winding around their fibrous supports; reaching past neighbouring cells to wrap themselves to the artificial scaffolding in a manner reminiscent of the way vines grow. They also observed plants cells taking on growth and structure of far greater complexity than has ever been seen before with plant cells, either in living tissue or cell culture.

"Previously, plant cells in culture had only been seen in round or oblong forms. Now, we have seen 3D cultured cells twisting and weaving around their new supports in truly remarkable ways, creating shapes we never thought possible and never seen before in any plant," said Wightman. "We can use this tool to explore how a whole plant is formed and at the same time to create new materials."

This ability for single plant cells to attach themselves by growing and spiralling around the scaffolding suggests that cells of land plants have retained the ability of their evolutionary ancestors – aquatic single-celled organisms such as Charophyta algae – to stick themselves to inert structures.

The scientists say the research "defines a new suite of techniques" for exploring cell-environment interactions, allowing greater understating of fundamental plant biology that could lead to new types of biomaterials and help provide solutions to sustainable biomass growth.

This story is adapted from material from Cambridge University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.