Breakthrough in lab-grown blood cells could transform regenerative medicine
A pioneering advance in lab-grown blood cells promises to accelerate regenerative therapies, improve drug screening, and provide new models for studying blood cancers like leukaemia. Researchers from the University of Cambridge have created embryo-like structures called hematoids that mimic early human blood and organ development. Although not embryos, these models reproduce crucial stages of development and begin producing blood cells after about two weeks in the lab.
What are hematoids and why do they matter?
Hematoids are stem-cell-based structures designed to imitate the initial formation of the human blood system and organs. By recapitulating early developmental milestones, the models allow scientists to observe processes that are normally invisible in utero. The Cambridge team emphasizes that while hematoids share developmental features with human embryos, they lack certain tissues, a yolk sac, and a placenta, hence they cannot develop into a fetus. This distinction is important for ethical and safety considerations while enabling rigorous scientific exploration.
Key milestones observed in the lab
From day two in the lab, the hematoids organized into three layers, which play a central role in shaping all organs and tissues. By day eight, researchers noted the appearance of cells that would later form the heart, signaling rapid progression through a human-like embryonic timeline. Around day 13, red patches emerged within the structures, interpreted as early blood formation. By roughly weeks four to five of natural human development, the team found the blood cells reached a developmental stage that is typically unseen in standard biological studies.
Implications for regenerative medicine and research
The capability to generate human blood cells in a controlled lab setting marks a meaningful step toward regenerative therapies. The prospect is particularly exciting because such approaches could use a patient’s own cells to repair damaged tissue, reducing the risk of immune rejection. Beyond therapies, the hematoid model offers a valuable platform for screening new drugs and evaluating how they interact with developing blood and immune cells. In addition, researchers hope to simulate blood disorders, including leukaemia, to better understand disease progression and to test potential treatments in a human-relevant context.
Towards new models of blood development
Co-first author Dr. Geraldine Jowett notes that hematoids capture the second wave of blood development, which can give rise to specialized immune cells such as adaptive lymphoid cells, including T cells. This insight points to possibilities for modeling both healthy and cancerous blood development, as well as for studying how the immune system forms in early life. Dr. Jitesh Neupane adds that the achievement is visible even without magnification, underscoring the tangible progress in understanding human foetal blood development in a lab setting.
Future directions and considerations
The Cambridge team has patented their work, signaling a move toward translating these findings into practical tools for medicine. The study, published in the journal Cell Reports and funded by Wellcome, opens doors to refining stem-cell technologies, improving the fidelity of developmental models, and accelerating the discovery of therapies that leverage a patient’s own cells. As with all cutting-edge biomedical research, ongoing work will focus on enhancing the precision of the models, confirming safety, and exploring how these blood-forming systems interact with other developing tissues.
In sum, the breakthrough in laboratory-grown hematoids represents a promising intersection of developmental biology and translational medicine. By simulating early human blood development, researchers are laying groundwork for regenerative treatments, more accurate disease models, and smarter drug screening pipelines that could ultimately improve patient outcomes.
