Scientists have grown embryo-like structures in the laboratory that produced human blood cells, marking a significant advance for regenerative medicine. The research, led by the University of Cambridge's Gurdon Institute, could one day enable patients in need of bone marrow transplants to be treated using their own cells.
The embryo models were created from human stem cells without the need for eggs or sperm, mimicking the earliest stages of human development. Dr Jitesh Neupane, first author of the study, described the moment blood appeared: 'It was an exciting moment when the blood-red colour appeared in the dish – it was visible even to the naked eye.'
By day two, the structures had self-organised into three germ layers – the foundations of the human body plan. By day eight, beating heart cells had formed, and by day 13, red patches of blood appeared. Blood stem cells from the model differentiated into various blood cell types, including red blood cells and immune white blood cells.
Unlike other methods, this approach mimics natural developmental processes without requiring extra proteins. Professor Azim Surani, senior author, said: 'Although it is still in the early stages, the ability to produce human blood cells in the lab marks a significant step towards future regenerative therapies.'
The model was designed to lack tissues that form the placenta and yolk sac, meaning it could not develop into a foetus. The findings offer potential for drug screening, studying early blood and immune development, and modelling blood disorders such as leukaemia.
