In the field of exploring the mysteries of life, stem cell research has achieved remarkable results. Since the emergence of stem cell related research in 1932, after nearly a century of development, the safety and potential of stem cells in tissue regeneration have also undergone extensive research and testing.

According to experts' statistics, as of the end of last year, more than 100 clinical trials had been approved or completed, as reported by the UK's Nature website. These trials aim to explore the potential of stem cells in the treatment of cancer, diabetes, epilepsy, heart failure and various eye diseases. Researchers predict that stem cell therapy may be about to turn a new page. It is expected that stem cell therapy can be used to treat diabetes, Parkinson's disease, eye diseases and even cancer within 5 to 10 years.

From concept proposal to application in treatment

In 1932, Soviet scientists first proposed the concept of stem cells and conducted related research, marking the beginning of the dominance of stem cells in the medical field. Subsequently, scientists isolated embryonic stem cells from mouse embryos, providing technical support for embryonic stem cell research and sparking a craze for human embryonic stem cell research.

In 1998, James Thomson, a scientist at the University of Wisconsin, isolated embryonic stem cells from human embryos and cultured them in vitro. Embryonic stem cells have pluripotency and can differentiate into different types of cells. This progress enables humans to use embryonic stem cells for regenerative medicine research (such as cell transplantation to regenerate body tissues and functions), and explore new ways to treat various difficult diseases.

However, embryonic stem cell research faces ethical challenges. In 2006, Japanese scientist Shinya Yamanaka introduced four transcription factors into adult cells and "reprogrammed" them back to a pluripotent state, creating induced pluripotent stem cells (iPS cells). The function of iPS cells is similar to that of embryonic stem cells, and they can differentiate into various tissues and organs. The birth of iPS cells not only solves the problem of embryonic stem cells, but also provides a new platform for personalized medicine and disease model research.

With the continuous advancement of technology, scientists have obtained a large number of specialized cells for brain, heart, lung tissue, etc. using human embryonic stem cells and iPS cells. The quality and purity of these specialized cells are sufficient for clinical use, opening a new chapter in stem cell therapy.

From Parkinson's disease to various cancers

Among the more than 100 clinical trials counted by experts, 12 are dedicated to using stem cells to treat Parkinson's disease, and 29 are aimed at eye diseases, especially age-related macular degeneration.

According to media reports in January this year, China's first iPSC derived cell therapy has made breakthrough progress in treating Parkinson's disease. The test results of the subjects 12 months after participating in the clinical trial showed significant improvements in their exercise ability and quality of life compared to before treatment. This clinical study was jointly conducted by Professor Liu Zhongmin's team from Shanghai Oriental Hospital and Shize Biotechnology.

Research on epilepsy is also worth paying attention to. In a clinical trial conducted by a neuron therapy company in the United States, surgeons integrated stem cells into the neural circuits of 15 epilepsy patients using stem cell therapy. After one year of transplantation, the frequency of severe epileptic seizures in two of the participants almost dropped to zero, and the effect had persisted for two years. The seizure frequency of most other participants also significantly decreased. The company reported that this therapy had no significant side effects and did not cause cognitive impairment. Based on the above effects, the "effective stem cell therapy" developed by teams including neuron therapy companies has also been named one of the "Top 10 Breakthrough Technologies" of 2025 by MIT Technology Review.

In 2014, Japanese scientists launched the first clinical trial using iPS cells to treat macular degeneration. Despite numerous difficulties, this attempt has brought new hope for the treatment of related eye diseases. In addition, in November last year, scientists from institutions such as Osaka University in Japan published a paper in The Lancet stating that they had restored vision in patients with corneal limbal stem cell deficiency for the first time by transplanting corneal tissue cultured from iPS cells. They also plan to launch a larger clinical trial in March this year to further evaluate the effectiveness of the therapy.

Stem cell therapy has also brought light to the treatment of diabetes. In 2014, Douglas Melton, a stem cell expert at Harvard University, and his colleagues cultivated the first functional pancreatic islet cells from a human embryonic stem cell line. Now, Melton and others are carrying out a trial for severe patients with diabetes in the United States Fortex Biological Pharmaceutical Company, using islet cells obtained by similar methods. The company stated that among the 12 patients who received full dose injections, 9 did not need to receive insulin injections again, and two could reduce the injection dose.

Chuck Murray, a stem cell biologist at the Keck School of Medicine at the University of Southern California, hopes to initiate a clinical trial to inject immature cardiomyocytes produced by iPS cells into the hearts of patients with moderate heart failure, testing their safety and feasibility.

In addition, scientists are using pluripotent stem cells to generate immune cells (T cells or natural killer cells) and testing their potential for treating a range of cancers. The midterm report shows that these treatments are not only safe, but also have significant effects in some cases: some participants have met the criteria for clinical cure.

Ethical and safety issues still need to be addressed

However, stem cell therapy still faces some obstacles on its development path.

Firstly, the superiority or inferiority of human embryonic stem cells and iPS cells as two types of cell therapy materials is still uncertain.

Despite ethical controversies surrounding the use of human embryos, many scientists still prefer to use human embryonic stem cells because they are the least interfered with pluripotent cell types. In theory, reprogramming adult cells may introduce oncogenic mutations into the genome. Some scientists believe that once choosing iPS cells, it is equivalent to adding additional risks to patients. However, some scientists believe that cancer risk is more of a hypothesis than a real threat.

In addition, how to prevent rejection reactions in transplanted cells has not been properly addressed. Although cell lines generated from iPS cells or human embryonic stem cells are convenient to use, patients typically require immunosuppressive therapy. Using cells obtained by reprogramming the patient's own skin or blood cells can avoid this need, but producing such cells is costly and takes several weeks to prepare.