Scientists Grew Dog Blood Cells in the Lab. They Are Not Ready for Transfusions Yet

When a dog needs an emergency transfusion, there is no universal bag of blood waiting on every veterinary shelf. Dogs have blood groups, compatible donors can be difficult to find, and veterinary blood-bank networks are far less developed than their human equivalents. In many clinics, a lifesaving transfusion still depends on recruiting a healthy donor dog at the right time.

A research team at Osaka Metropolitan University has taken an early step toward a different source. The scientists generated red-blood-cell-like cells from canine induced pluripotent stem cells, or iPS cells, and used genome editing to watch a key stage of their development in real time. The peer-reviewed study appeared online in Stem Cells Translational Medicine on 20 July 2026.

Turning an adult cell back into raw material

Induced pluripotent stem cells begin as ordinary adult cells that have been reprogrammed into a flexible state. In principle, they can then be guided toward many specialized cell types. Their ability to multiply for long periods makes them attractive as a possible starting material for manufactured blood.

The researchers cultured canine iPS cells in small clusters and changed their growth conditions in stages to mimic the body's blood-development process. Blood progenitor cells emerged, followed by reddish cells containing hemoglobin, the protein that carries oxygen in natural red blood cells.

That result alone did not tell the team precisely when the cells were committing to the red-cell pathway. A major practical obstacle was the lack of widely available antibodies that reliably detect the canine version of glycophorin A, or GYPA, a protein used as a marker of red blood cell development.

CRISPR turned development into a green signal

To solve the tracking problem, the researchers used CRISPR-Cas9 genome editing. They inserted instructions for a green fluorescent protein alongside the canine GYPA gene. When a developing cell switched on GYPA, it also produced a green signal that researchers could see and measure.

Under the team's optimized culture conditions, more than 96% of the analyzed cells expressed GYPA. The reporter system therefore did more than produce a striking laboratory image. It created a tool for comparing recipes, timing and cell lines as scientists search for conditions that yield more mature cells.

This combination of reprogrammed cells and real-time genetic reporting is the technological heart of the study. Instead of inspecting only the end product, researchers can follow differentiation as it happens and identify where the process succeeds or stalls.

Why veterinary medicine needs another supply route

Red blood cell transfusions are used after major blood loss, during surgery and in severe anemia. Dogs, like humans, have different blood types, so compatibility matters. Maintaining a large pool of screened donor animals and collecting, testing and storing blood is costly, which helps explain why supplies are uneven.

If scientists could one day make mature canine red blood cells reliably and at scale, banks might be able to prepare more standardized products from carefully selected cell lines. That could reduce dependence on donor dogs and make rare compatible blood easier to obtain. It could also give researchers a controlled system for studying inherited blood disorders and testing treatments.

The work may have a second audience. Dogs naturally develop several diseases that resemble human conditions and share our environment. A robust canine platform could therefore help researchers evaluate the production and behavior of iPS-derived blood products before related approaches advance in human medicine.

This is not artificial blood ready for a clinic

The numbers also reveal the central limitation. A mature mammalian red blood cell normally ejects its nucleus, creating more space for hemoglobin and helping it bend through tiny blood vessels. In this experiment, only about 3% of the generated cells became enucleated.

The researchers also detected immature forms of hemoglobin. They have not yet demonstrated that the cells transport oxygen adequately, deform safely through narrow vessels, survive for a useful period inside an animal or avoid harmful immune reactions. None of the reported cells was transfused into a dog.

Producing a high percentage of cells with GYPA is therefore not the same as producing a high percentage of functional red blood cells. The study establishes a differentiation and measurement platform, not a replacement for donated blood.

The difficult engineering begins now

The next task is to discover which biological signals push far more cells through the final stages of maturation. Researchers will also need to determine why some iPS cell lines perform better than others, design scalable and contamination-controlled manufacturing, and test safety and function in animals before clinical trials could be considered.

Cost will matter too. A laboratory process can be scientifically impressive yet remain impractical if each unit requires expensive growth factors, lengthy culture or complex quality testing. Any future product would also face veterinary regulation and blood-group matching.

For now, the achievement is best understood as a new way to study the problem. The team has made canine red-cell development visible and repeatable enough to optimize. It is not a bag of synthetic blood, but it may be the platform on which one is eventually built.