A Day in the Life: Tom Houghton, Technician

	Tom Houghton, Research Technician

As a research technician the focus of my job is to carry out the nuts and bolts of research here at the centre. In the past few months we have been concentrating our efforts on developing a new method for the culture of human skin cells. Instead of culturing cells on the base of plastic flasks, we have successfully grown patient cells on the surface of microscopic beads that are constantly stirred in a liquid nutrient medium.

The picture (left) shows one of these beads under a microscope. The bead has been stained so as to make the attached cells on its surface more clearly visible.

In the picture it is possible to distinguish the outline of the transparent bead which is covered by numerous human fibroblast cells. These cells have been chemically stained so that a distinction can be made between living cells (blue) and dead cells (red).

So why grow cells on beads? This research is an evolution of the 'sprayed skin' technology that the centre has pioneered in the past. Previously, patient cells could be grown up in the traditional way in plastic flasks and then harvested and sprayed onto the burnt area to accelerate wound closure. However, the harvesting step is particularly destructive because strong enzymes are used to detach the growing cells from the base of the flask. The effect of this trauma to the cells is that they go into an inactive phase – exactly what you want to avoid if spraying cells onto a patient.

However, the beads may be the answer. With this new technique, the beads themselves (with cells attached) can be sprayed onto the patient. The cells, still in their active phase will migrate off the bead onto the wound bed.

The problem so far is that the type of bead in the picture is unsuitable for clinical use – if it was to be spayed onto a wound in its present form, the patients immune system would recognise it as a foreign body and raise an immune response. What is needed is a bead that can both facilitate the growth of cells and that will biodegrade when on the patient into harmless by-products. The answer may lie with a novel material under development as a potential dressing which can be manufactured into thin sheets. However, we have recently managed to form pure beads (above) of this novel material and tests with patients cells are currently underway.