Scientists have successfully grown human embryo-like structures in the lab that produced blood cells — a major step toward developing regenerative therapies using patients’ own cells.
The research, led by Dr Jitesh Neupane and Prof Azim Surani at the University of Cambridge’s Gurdon Institute, used stem cells to mimic natural embryonic development without the need for eggs or sperm. “It was an exciting moment when the blood-red colour appeared in the dish – it was visible even to the naked eye,” said Neupane.
The model replicates the key stages of early human development, forming three germ layers within two days and producing beating heart cells by day eight. By day 13, red patches of blood appeared, and the lab-grown blood stem cells were shown to mature into both red and white blood cells.
Unlike previous techniques, this approach does not rely on added growth factors but instead mirrors how tissues form naturally in the embryo. The work could one day allow doctors to create fully compatible blood for transplants or treat disorders such as leukaemia using a patient’s own cells.
The team emphasised that the structures cannot develop into a foetus, as they lack the tissues required for a placenta, yolk sac or brain. “Although it is still early days, this is a significant step toward future regenerative therapies,” said Surani.

