In an astonishing breakthrough that could allow doctors in the future to repair diseased tissues with a patient's own cells, scientists have created embryonic-like stem cells by simply bathing ordinary skin or blood cells in a weak acid solution, a report said.

Researchers at the Riken Centre for Developmental Biology in Japan have announced the breakthrough in the journal Nature. It has been welcomed in Britain as an important step towards using stem cells routinely in medicine without the ethical or practical problems of creating human embryos or genetically modified cells, said a report in The Independent.

Although the research was carried out on laboratory mice, scientists believe that the same approach should also work on human cells.

The method radically changes the way "pluripotent" stem cells - which can develop into any of the specialised tissues of the body - can be created from a patient's own cells as part of a "self-repair" kit.

"Once again Japanese scientists have unexpectedly rewritten the rules on making pluripotent cells from adult cells....that requires only transient exposure of adult cells to an acidic solution. How much easier can it possibly get?" said Professor Chris Mason, chair of regenerative medicine at University College London.

The scientists believe that the acidity of the solution created a "shock" that caused the blood cells of adult mice to revert to their original, embryonic-like state. From this pluripotent state, the newly created stem cells were cultured in specially prepared solutions of growth factors to develop into fully mature cells, including an entire foetus.

Professor Robin Lovell-Badge of the Medical Research Council's National Institute for Medical Research, said: "It is going to be a while before the nature of these cells are understood, and whether they might prove to be useful for developing therapies, but the really intriguing thing to discover will be the mechanism underlying how a low pH shock triggers reprogramming. And why it does not happen when we eat lemon or vinegar or drink cola?"