I'm starting from scratch
The basics in five minutes, without technical terms.
Stem cells, explained clearly.
What they are, what they really treat today and what is still experimental. A guide written for readers starting from scratch, with the official sources and the studies the information comes from.
Informational content. It does not replace medical advice, a clinical protocol or a regulatory assessment. In the stem cell field, the situation can vary by country and indication, and can change as the evidence is updated.
Where to start
Choose your question
Can they treat my disease?
The treatments approved today, disease by disease, and what is still experimental.
I've been offered a stem cell treatment
The warning signs, the questions to ask and where to report a suspicious offer.
I want to donate
How to become a bone marrow donor and what to do with cord blood, in Italy.
Who works on this in Italy
Centers, researchers and national networks, with official sources and no rankings.
How we got here
The discoveries from 1961 to the first iPS cell therapies in 2026.
The difficult words
Pluripotent, autologous, iPSC, advanced therapy: definitions with sources.
Frequently asked questions
Short answers, with sources, to the most common questions.
How we check
The site's method, the sources it uses and how to read scientific evidence.
The basics in five minutes
Stem cells in plain language
- What they are. Almost every cell in the body has a fixed job: a skin cell stays a skin cell. Stem cells, by contrast, can make copies of themselves and turn into specialized cells. Those in the bone marrow, for example, produce red blood cells, white blood cells and platelets throughout life.
- What they treat today. The most solid use, for decades, has been the blood stem cell transplant (often called a “bone marrow transplant”) for leukemias, lymphomas, myeloma and other blood diseases: in Italy, 5,258 transplants in 2025. There are also about twenty stem cell-based medicines authorized around the world, almost all for rare and very specific diseases. See the list.
- What is still experimental. For Parkinson's disease, heart disease, type 1 diabetes or spinal cord injuries there are serious clinical trials, and in Japan the first conditional approvals, but no routine therapies in Europe.
- What is not proven. For autism, ALS, Alzheimer's disease or aging, there are no stem cell medicines approved in Europe or the United States, and controlled trials so far have not shown definite benefits. How to guard against false promises.
- How to help. People aged between 18 and 35 can join the bone marrow donor registry; at childbirth, cord blood can be donated to a public bank. How to do it.
In brief
Six points to get your bearings quickly
They are not a single category
Embryonic, adult or somatic, cord-derived stem cells and iPSCs are not equivalent in origin, biological flexibility and use.
Research serves several purposes
It helps us understand development, disease, drug response, organoids and cell therapies, not just produce treatments.
The clinic and the lab are not the same
A preclinical finding does not count as clinical efficacy. Between the two worlds lie trials, quality controls and strict rules.
Established uses are specific
The main historical benchmark remains hematopoietic stem cell transplantation for defined indications.
Many areas are promising but not standard
Ophthalmology, neurology, cardiology and orthopedics are fields of great interest, but with very different levels of evidence.
Commercial language is confusing
Words such as regenerative, natural, autologous or anti-aging can be used in misleading ways if they are not put in context.
Definition
What stem cells are
A stem cell has two fundamental properties: it can self-renew and, under the right conditions, it can generate more specialized cells. These properties do not always have the same strength and do not automatically imply therapeutic usefulness.
The topic matters for at least four reasons: understanding development, modeling diseases, testing drugs and, in some settings, controlled clinical use.
What it really means
“Stem cell” is a biological term, not a clinical slogan.
- Self-renewal: the cell generates other cells similar to itself.
- Differentiation: it can produce cells with more specific functions.
- Potency: not all stem cells have the same range of possible development.
- Context: the same word changes meaning between the lab, trials and clinical practice.
A short history
Some milestones that changed the field
First experimental evidence
Research on hematopoietic cells helps define the modern concept of the stem cell.
Human embryonic stem cells
The field receives a strong boost from the isolation of human pluripotent cell lines, and from the ethical debate that comes with it.
iPSCs arrive
Reprogramming adult cells into a pluripotent-like state changes research and opens new experimental paths.
More rigorous translation
The question is no longer just “can we do it?” but “when is it safe, reproducible and useful enough to become clinical practice?”
Evidence ladder
How a field moves from promise to standard practice
-
01
Basic research
Understanding fundamental biology and identifying new opportunities.
-
02
Preclinical research
Studies in cells and animals to explore potential and mechanisms.
-
03
Controlled clinical trials
Rigorous testing to assess safety and efficacy.
-
04
Standard clinical use
Interventions become part of routine care and of clinical guidelines.
Recent recognition
Real milestones, not promises: the latest approvals
Japan, March 6, 2026
The world's first iPSC-derived therapies
Japan's Ministry of Health grants conditional and time-limited approval to AMCHEPRY (raguneprocel), dopaminergic neural progenitors for Parkinson's disease, and RiHEART, cardiomyocyte sheets for severe heart failure: both derived from iPS cells. Efficacy must be confirmed within 7 years.
FDA, December 9, 2025 · EU, January 9, 2026A blood stem cell gene therapy born in Italy
Waskyra (etuvetidigene autotemcel) uses a lentiviral vector to add a working copy of the WAS gene to the hematopoietic stem cells of patients with Wiskott-Aldrich syndrome. It grew out of research at SR-Tiget in Milan: according to Fondazione Telethon, it is the first ex vivo gene therapy brought to approval by a nonprofit organization.
FDA, December 18, 2024First mesenchymal cell-based therapy approved in the US
The FDA approves Ryoncil (remestemcel-L), a therapy based on mesenchymal stromal cells from bone marrow, for steroid-resistant graft-versus-host disease in children. It is the first MSC product to obtain FDA approval.
FDA, December 8, 2023First gene therapy using CRISPR editing of blood stem cells
The FDA approves Casgevy (exagamglogene autotemcel) for sickle cell disease: the patient's hematopoietic stem cells are modified with CRISPR/Cas9 to increase fetal hemoglobin. It is the first gene therapy based on genome editing to be approved in the United States.
Scientific timeline
A more detailed sequence of the major discoveries
Original papers
Entries with a PMID or DOI link to peer-reviewed scientific papers or to primary bibliographic references.
Historical or institutional sources
Some historical and regulatory milestones are anchored to ASH, the Nobel Prize, EMA or FDA, when the relevant point is the recognition or the regulatory status.
Interpretive limit
A historical milestone is not the same as general clinical proof. That is why each card keeps impact, limit and level separate.
1961
Discovery: McCulloch and Till provide classic experimental evidence that hematopoietic stem cells exist in the bone marrow.
Impact: they lay an experimental foundation for the modern idea of stem cells in adult tissues.
Limitation: the context is still confined to hematopoietic biology, not general pluripotency.
Level: basic1962
Discovery: John B. Gurdon shows that the nucleus of a differentiated cell can be reprogrammed.
Impact: it opens the conceptual framework that will make cell reprogramming plausible decades later.
Limitation: this is not yet a clinical technology or modern iPS cells.
Level: basic1968-1969
Discovery: the first successful allogeneic hematopoietic cell transplants, mainly in severe immunodeficiencies.
Impact: the field enters modern clinical medicine and shows that cell transplantation can become a life-saving therapy.
Limitation: very specific indications, high procedural complexity, toxicity and compatibility remain central.
Level: clinical1981
Discovery: isolation of mouse embryonic stem cells by Evans and Kaufman.
Impact: it changes developmental biology and makes pluripotency testable in the laboratory.
Limitation: this is a mouse system, not yet human pluripotent cells.
Level: basic1987-1989
Discovery: isolation of mouse and human hematopoietic stem cells, with a better experimental definition of HSCs.
Impact: it strengthens the bridge between biological definition, transplantation and the development of more refined protocols.
Limitation: the characterization remains limited to the hematopoietic compartment.
Level: translational1990
Discovery/recognition: Nobel Prize to E. Donnall Thomas for his contribution to the development of hematopoietic transplantation.
Impact: it confirms the value of hematopoietic cell transplantation as a major chapter of modern medicine.
Limitation: the recognition concerns a specific field, not all stem cell applications.
Level: clinical1998
Discovery: James Thomson and colleagues describe human embryonic stem cell lines derived from blastocysts.
Impact: it opens a new phase of research on human pluripotent cells and on controlled differentiation.
Limitation: ethical questions and problems of clinical translation are central from the start.
Level: basic2006
Discovery: Takahashi and Yamanaka report generating iPS cells from mouse fibroblasts using defined factors.
Impact: it changes the field of cell reprogramming and redraws the relationship between adult cells and pluripotency.
Limitation: it is still a mouse system, and the biological safety of reprogramming remains an open question.
Level: basic2007
Discovery: human iPS cells arrive: the work of Takahashi and colleagues extends reprogramming to adult human fibroblasts.
Impact: the technology becomes central to disease models, pharmacology and the biology of human pluripotency.
Limitation: challenges remain in genomic stability, quality and clinical transferability.
Level: basic2009
Discovery: organoids from a single Lgr5+ stem cell: the work of Sato and Clevers shows that single intestinal cells can build crypt-villus structures in vitro.
Impact: it speeds up disease modeling, tissue physiology research and experimental testing on organoids.
Limitation: an organoid is not a complete organ and is not the same as a clinical therapy.
Level: translational2012
Discovery/recognition: Nobel Prize to Gurdon and Yamanaka for showing that mature cells can be reprogrammed to a pluripotent state.
Impact: it consolidates reprogramming as a major biological paradigm in the field.
Limitation: scientific recognition does not remove the barriers to safe, standardized clinical applications.
Level: institutional2015
Discovery/approval: Holoclar becomes the first stem cell-based product recommended/approved in the EU for a specific ophthalmological indication.
Impact: it marks an important step in the regulated clinical translation of advanced cell therapies.
Limitation: this is a very specific indication and product, not a general validation of the field.
Level: regulatory2019-2021
Regulatory event: regulatory agencies focus on unapproved products: the FDA and other bodies step up public communication against unvalidated regenerative medicine offers.
Impact: they make clear to patients and clinicians that many offers on the market are not approved or adequately tested treatments.
Limitation: regulatory communication alone does not solve the problem of aggressive marketing or medical tourism.
Level: regulatory2024
Approval: Ryoncil is approved by the FDA as the first mesenchymal stromal cell therapy for steroid-refractory acute GVHD in pediatric patients.
Impact: it shows that the field keeps advancing, but for extremely specific indications and under strict regulation.
Limitation: it does not justify generalizations about the value of all commercial mesenchymal or regenerative therapies.
Level: regulatory2025
Approval: the EU grants conditional marketing authorization to Zemcelpro (dorocubicel), cord blood stem cells partly multiplied in the laboratory, for adults with blood cancers who need an allogeneic transplant and have no other suitable donor cells available.
Impact: it widens the options for hematopoietic transplantation for people who cannot find a compatible donor.
Limitation: conditional marketing authorization, granted on less complete data than usual because of an unmet medical need; narrow indication.
Level: regulatory2025-2026
Approval: the FDA (December 9, 2025) and then the EU (January 9, 2026) approve Waskyra (etuvetidigene autotemcel): in the laboratory, a working copy of the WAS gene is added to the patient's hematopoietic stem cells using a lentiviral vector. The authorization holder is Fondazione Telethon; the therapy grew out of decades of research at SR-Tiget in Milan.
Impact: it brings blood stem cell gene therapy to a rare inherited immunodeficiency; according to Telethon, it is the first ex vivo gene therapy taken from research to approval by a nonprofit organization.
Limitation: narrow indication (WAS gene mutation, transplant appropriate but no suitable HLA-matched donor); it is gene addition, not genome editing like Casgevy.
Level: regulatory2026
Approval: on March 6, 2026, Japan's Ministry of Health authorizes the world's first two products derived from iPS cells: AMCHEPRY (raguneprocel), allogeneic dopaminergic neural progenitors for motor symptoms of Parkinson's disease that do not respond adequately to medication, including levodopa; and RiHEART, allogeneic cardiomyocyte sheets applied to the surface of the heart in severe ischemic heart failure.
Impact: twenty years after Takahashi and Yamanaka's first iPS cells (2006), cell reprogramming reaches products authorized for clinical use.
Limitation: conditional and time-limited approval, granted with safety confirmed and efficacy considered plausible: efficacy must be demonstrated within 7 years. It applies only in Japan and is not the same as routine use.
Level: regulatory| Year | Discovery | Level | Impact | Limit | ID | Primary source |
|---|
Map of types
Three main families that should not be confused
Embryonic
ResearchThey have high pluripotency and great value for biological understanding, but they raise ethical questions and challenges in controlling differentiation.
- Origin
- Early stages of embryonic development
- Capacity
- Pluripotent
- Value
- Basic research, models, development
- Limits
- Ethics, safety, biological control
Adult or somatic
Selective useThey live in tissues that are already formed. They are often multipotent and include the cells used in the most established clinical uses.
- Origin
- Bone marrow, blood, adult tissues
- Capacity
- Often multipotent
- Value
- Research and some clinical applications
- Limits
- More limited plasticity
iPSCs
Advanced researchAdult cells reprogrammed into a pluripotent-like state. They are crucial for modeling diseases, creating testing platforms and studying differentiation. In 2026 Japan granted conditional approval to the first two iPSC-derived products, for Parkinson's disease and heart failure.
- Origin
- Reprogrammed mature cells
- Capacity
- Induced pluripotency
- Value
- Disease models, research into new drugs, experimentation
- Limits
- Stability, quality, clinical transfer
Origin and sourcing
How they are obtained and why they are not equivalent
The most discussed sources include embryos, adult tissues, mobilized peripheral blood, bone marrow, cord blood and reprogrammed cells.
Each source changes availability, biological flexibility, immunological compatibility, manufacturing complexity and ethical profile.
From adult tissues
They are often the practical reference for established clinical use in hematology.
From the umbilical cord
They can be relevant for transplantation and storage, but they are not a universal therapy.
From reprogramming
iPSCs are a huge methodological leap, but their clinical use requires rigorous processes and controls.
From research to the clinic
The steps that separate a promise from a standard of care
Basic research
Biological mechanisms, development, differentiation, tissue maintenance and cell stability.
Preclinical research
Cell and animal models for biological plausibility, initial safety and product behavior.
Clinical trials
Safety, dose, patient selection, efficacy and structured monitoring of adverse events.
Authorization and practice
Manufacturing quality, regulatory oversight, standardization, traceability and use in well-defined indications.
Applications
Where they are used, where they are studied, where caution is needed
Hematology and immunology
Established useBlood stem cell transplants have been used for decades for leukemias, lymphomas, myeloma and some diseases of the blood and immune system. In recent years, gene therapies on the patient's stem cells have been added, such as Casgevy (sickle cell disease and thalassemia) and Waskyra (Wiskott-Aldrich syndrome).
Ophthalmology
Approved for specific casesHoloclar, authorized in the EU since 2015, rebuilds the surface of the eye with the patient's limbal stem cells after severe burns. For macular degeneration and other retinal diseases there are only early-stage studies.
Dermatology and epithelial tissues
Targeted applicationsSkin grown from the patient's cells has been used for decades in people with severe burns. For epidermolysis bullosa, genetically corrected skin has given important results in individual cases; in the US, a therapy of this kind has been approved since 2025.
Neurology
Research and trialsFor Parkinson's disease, spinal cord injuries and stroke there are clinical trials; in Japan, since 2026, an iPSC-derived product for Parkinson's has had conditional approval. In highly active multiple sclerosis, autologous blood stem cell transplantation, which acts on the immune system, is used in selected cases. For ALS, Alzheimer's disease and autism there is no proven therapy.
Cardiology
Research and trialsTwenty years of studies with cells injected into the heart have produced mostly disappointing results. In Japan, since 2026, iPSC-derived heart cell sheets have had conditional approval for severe ischemic heart failure.
Orthopedics and regenerative medicine
Highly heterogeneousThis is one of the fields where commercial language creates the most confusion. Procedures, evidence and regulation must be told apart case by case.
The full table, disease by disease and with sources, is on the What stem cells really treat page.
A qualitative representation, not a numerical metric: it summarizes the cards above and adds no further data.
Where it is used today
The most solid ground remains very specific
When we talk about “stem cell therapies” in a truly standardized sense, the clearest case remains that of hematopoietic stem cells in defined settings.
This does not diminish the importance of the rest of the field. Rather, it helps bring order to biology, research, trials and authorized clinical practice.
What not to oversimplify
The words that change the meaning
Autologous does not automatically mean safe. Regenerative does not mean proven. Experimental does not mean already available. Natural does not mean risk-free.
These nuances are not semantic details: they are the heart of critical judgment on the topic.
Regulation
Why regulation matters as much as biology
A cell product is not judged only on its scientific rationale. Process, traceability, purity, stability, reproducibility, documentation and surveillance of adverse events all count.
The FDA, the ISSCR and national and European authorities insist on this point: many commercial offers fall outside approved or adequately controlled pathways.
Minimum checklist
- Clinical trial: does it really exist, and can it be traced?
- Indication: for which specific condition?
- Product: how is it obtained and controlled?
- Authorization: what is its regulatory status in the country?
- Risks: are they described clearly, not hidden?
Ethics
It is not just a technical question
Origin of the biological material
Embryonic cells raise ethical questions that differ from those raised by adult, cord blood or reprogrammed cells.
Consent and communication
How goals, limits and risks are explained is an essential part of clinical ethics and of science communication.
Access and cost
Cell therapies can be complex and expensive. Equitable access is a concrete issue, not a theoretical one.
The boundary with marketing
When the commercial promise goes beyond the available data, the problem is not only scientific but also ethical and regulatory.
Risks, limits and hype
The points this site must not hide
Promise
“This therapy can regenerate many organs.”
Critical check
A very broad promise is a reason for caution. Established clinical applications are specific, not generic.
Promise
“If the cells come from the patient, then they are safe.”
Critical check
What counts is the whole process: collection, manipulation, purity, dose, clinical indication, follow-up.
Promise
“There is already a study, so it can be done right away.”
Critical check
An early study may investigate only safety or feasibility, not definitive efficacy.
Promise
“Regenerative” automatically means advanced and useful.
Critical check
The word regenerative is used in very different contexts. Without a precise definition it can create false expectations.
Technical risks
Incomplete differentiation, genetic instability, unwanted growth, contamination, manufacturing quality problems.
Clinical risks
Rejection, immunogenicity, complications of the procedure, unpredictable response, long and demanding follow-up.
Information risks
Anecdotal testimonials, anti-aging claims, vague use of “miracle” or “natural cure”, websites with no clear regulatory status.
Key figures
Some people who have shaped the field
This is not a ranking. These are useful names for finding your way, grouped by role: international research, Italian research that has reached patients, clinical practice and outreach in Italy.
Shinya Yamanaka
International researchIn 2006 (in mice) and 2007 (in humans) he showed how to reprogram adult cells into cells similar to embryonic ones: iPS cells. Nobel Prize 2012 with John Gurdon.
George Daley
International researchHematologist and researcher, a prominent figure in stem cell biology and translational medicine.
Widely cited for bridging basic research, iPSCs and biomedical applications.
Michele De Luca and Graziella Pellegrini
Italian researchAt the Centro di Medicina Rigenerativa “Stefano Ferrari” (Center for Regenerative Medicine) in Modena, they study epithelial stem cells. Their research led to Holoclar, the first advanced therapy medicinal product containing stem cells to be authorized in the EU (2015), used to rebuild the surface of the eye after severe burns.
Fernando Colao
Clinical practice and outreachOrthopedic surgeon and adjunct lecturer at the Università Europea di Roma (European University of Rome). He takes part in Italian public initiatives on stem cells and regenerative medicine in orthopedics.
Centers and societies to follow
Profile: NIH Stem Cell Information, ISSCR, FDA, EuroStemCell, Harvard Stem Cell Institute, Fondazione Telethon and SR-Tiget, Centro di Medicina Rigenerativa “Stefano Ferrari” (Unimore).
For such a fast-moving topic, official centers and societies are often more useful than individual names for staying up to date.
Extended FAQ
Questions that help you read the topic better
Are stem cells and regenerative medicine synonyms?
No. Regenerative medicine can include cells, tissues, biomaterials, tissue engineering and combined approaches. Stem cells are only one part of the picture.
Is autologous always better than allogeneic?
No. It depends on the indication, the product, feasibility, the time available and the immunological profile. There is no single answer that holds for every situation.
Why are iPSCs so important even though they are not yet a routine therapy?
Because they make it possible to create disease models, test drugs, study differentiation and personalize many lines of research.
How can you recognize an unreliable claim?
If it promises very broad results, does not make clear the indication and regulatory status, relies only on testimonials or uses the term “stem cells” without defining the product, caution is needed.
Does the fact that a center is private automatically make the treatment suspect?
No. The point is not public versus private, but transparency, protocol, quality, evidence, approvals and follow-up.
Glossary
Essential terms so you don't get lost
Self-renewal
The ability to produce new cells similar to itself.
Differentiation
The transition toward more specialized cell states.
Pluripotent
Able to generate many of the body's cell types.
Multipotent
Able to generate several cell types within a narrower range.
iPSC
Somatic cells reprogrammed into a pluripotent-like state.
Autologous
Biological material obtained from the same patient.
Allogeneic
Biological material obtained from another person.
Clinical trial
A structured study to assess safety and efficacy in people.
Organoid
A three-dimensional model that reproduces some aspects of a tissue or organ.
Sources and verification
References:
Institutional and official sources
- NIH Stem Cell Information
- NIH Common Fund: Stem Cells
- MedlinePlus: Stem Cells
- FDA: Important Patient and Consumer Information About Regenerative Medicine Therapies
- FDA Consumer Alert on Regenerative Medicine Products
- ISSCR Guidelines for Stem Cell Research and Clinical Translation
- EuroStemCell: Regulation of unproven stem cell therapies
- Università Europea di Roma: Fernando Colao (in Italian)
- GVM: Dr. Fernando Colao (in Italian)
- Versiliana Festival: stem cell event with Fernando Colao (in Italian)
- Unimore, Centro di Medicina Rigenerativa “Stefano Ferrari”: Michele De Luca and Graziella Pellegrini (in Italian)
- JST Science Japan: first approvals of iPSC-derived products (2026)
- Fondazione Telethon: approval of Waskyra
- EMA: Zemcelpro
- Harvard Stem Cell Institute: George Daley and research on iPS cells
- Gladstone: Shinya Yamanaka
Last editorial update: October 2, 2026.