Scientists believe they have found a way to get plentiful stem cells from umbilical cord blood to treat people with diseases.
The researchers plan to make tissues for transplant from the cells
Stem cells have the potential to turn into many different types of tissue, but using embryonic stem cells is controversial.
UK and US team believe they have found a way round this using cord blood and space technology borrowed from NASA.
Their microgravity method is described in the journal Cell Proliferation.
Dr Colin McGukin and Dr Nico Forraz from Kingston University in the UK, working with colleagues at the University of Texas Medical Branch at Galveston, have identified cells within human umbilical cord blood that appear to be very similar to embryonic stem cells.
Some of these cells expressed the same proteins or markers as embryonic stem cells, and were able to develop into liver cells.
However, they have not yet demonstrated that these cells do indeed have the potential to become any type of cell - the hallmark of a true stem cell, which is called pluripotency.
Lessons from space
They plan more work to see if they can make liver and pancreatic tissue from the cells to transplant into people with diseases such as diabetes.
From about 40-100 millilitres of cord blood they have been able to multiple the cells to numbers large enough for treatment thanks to space technology involving near-zero gravity.
When cells are cultured in the Earth's normal gravity they tend to grow relatively slow and as a flat layer.
At microgravity they grow much quicker and in three dimensions, mimicking the way organs grow in the embryo in the womb.
Dr McGuckin said their work was very exciting because it offered a way of treating many, many people.
"Cord blood is great because it is normally disposed of. It's ethically very acceptable to most of the world."
He said the supply was plentiful, with one hundred million babies being born every year.
"This means you have 100 million times a chance to find cells that have the same immunology as you and won't be rejected when they are transplanted into you."
He said that because many centres in the UK already banked cord blood, which is routinely screened for viruses like HIV, there was no real risk of any transplant from this source passing on infections.
Also, because the cord cells could be selected to be a good match for the transplant recipient, the likelihood of a tumour developing - one of the safety concerns raised about embryonic stem cell treatments - was also very small.
Dr Stephen Minger, director of the King's College London stem cell biology laboratory, said: "This is interesting work but it is preliminary.
"What they have not yet show is that the cells are pluripotent - that is capable of making cells from all three germ layers."