Blog

The 2012 Nobel Prize in Physiology or Medicine has been jointly awarded to Sir John B. Gurdon and Professor Shinya Yamanaka. They received the award ‘for the discovery that mature cells can be reprogrammed to become pluripotent’. What does that mean?

Humans are made of many tissues: bone, skin, muscle and more. Look at the tissues under a microscope and you’ll see they are made of cells. Cells are the building blocks of life.

Clearly a bone doesn’t look like an eyeball. They are made of different combinations of cell types. An adult human is composed of trillions of cells of many types, but all humans start out as a single, fertilised egg cell. After fertilisation, this cell starts to split, forming new cells. There are cells that develop which have the potential to form any type of cell. Some stem cells, which can go on to form most other cells, are said to be ‘pluripotent’.

Eventually, as the foetus grows, these pluripotent cells are said to specialise – that is they mature into specific types of cells. Some will become skin cells while others will form muscles and other body parts. Originally, the theory was that once a cell matured into one cell type, it couldn’t become another cell type – for example, a white blood cell couldn’t become a neuron cell in the brain.

The work of John and Shinya showed this isn’t the case. Both were able to take mature, specialised cells and show that they could be changed, or ‘reprogrammed’, to revert to immature cells. These cells could then mature into another type of cell.

Their discoveries have helped scientists better understand the development of cells and cell specialisation. There are also a number of medical applications, to treat diseases such as cystic fibrosis and Huntington’s disease, made possible by their work.