Types of stem cells, explained
What makes a cell a stem cell? Two abilities: it can copy itself (self-renewal), and it can give rise to more specialized cells (differentiation). Scientists group stem cells by how many cell types they can become, a property called potency.
This guide walks through each group, then explains umbilical cord mesenchymal stem cells (UC-MSCs) and exosomes, the two biologics our medical team works with at OmniStem.
Stem cells by potency
| Potency | What the cells can become | Examples |
|---|---|---|
| Totipotent | Every cell type, including the placenta | The fertilized egg, or zygote, and the first cells after it divides |
| Pluripotent | Nearly every cell type in the body, but not a whole organism | Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) |
| Multipotent | Several cell types within one family | Mesenchymal stem cells (MSCs), hematopoietic or blood-forming stem cells, and neural stem cells |
| Oligopotent | A few closely related cell types | Lymphoid progenitors, which produce lymphocytes |
| Unipotent | One cell type | Muscle satellite cells |
ESCs come from the inner cell mass of an early embryo (blastocyst), which is why their use is debated. iPSCs are adult cells, often from skin, reprogrammed in a laboratory to behave like ESCs; they offer a similar range without using embryos. Both remain mostly in research and early clinical trials.
Multipotent cells are the ones used in most current treatments. Hematopoietic stem cells are the basis of bone marrow transplants. MSCs are found in bone marrow, fat, and umbilical cord tissue, and in the laboratory they can form bone, cartilage, and fat cells.
What UC-MSCs are
UC-MSCs come from Wharton’s jelly, the soft connective tissue inside the umbilical cord. The cord is donated with consent after birth, tissue that would otherwise be discarded, and collection involves no procedure on mother or baby.
In laboratory comparisons with bone marrow MSCs, UC-MSCs divide faster and keep their properties through more rounds of expansion (Arutyunyan et al., 2016). They also carry low levels of the surface markers that trigger immune rejection. That allows allogeneic use: cells from one screened donor given to a different patient.
How MSCs act in the body
Early research assumed MSCs repaired tissue by turning into new cells. Later work showed that few infused cells stay in the body for long, and that most of their effect comes from the molecules they release. For this reason Arnold Caplan, the scientist who named mesenchymal stem cells, proposed in 2017 renaming them “medicinal signaling cells” (Caplan, 2017).
In laboratory and animal studies, those molecules adjust immune cell activity and lower inflammatory signals. They also support the growth of new blood vessels and limit scar tissue. Human studies are now testing which of these effects carry over to specific conditions.
What exosomes are
Exosomes are vesicles about 30 to 150 nanometers across that cells release to send signals to other cells (Kalluri and LeBleu, 2020). They carry proteins, lipids, and RNA. MSC-derived exosomes carry much of the signaling described above, which led researchers to study them as a therapy on their own (Phinney and Pittenger, 2017).
Exosomes contain no living cells, so they cannot divide or grow in the body. In animal studies, some exosomes have crossed the blood-brain barrier; whether that holds in people is still under study. No exosome product has FDA approval in the United States.
Areas of clinical focus at OmniStem
Our medical team evaluates UC-MSC and exosome protocols for joint pain and sports injuries, back pain and spine disorders, autoimmune conditions, neurological and cognitive support, pulmonary health, healthy aging and longevity, hair loss, and sexual health. Eligibility, protocol, and expected outcome are decided case by case after a medical review.
How treatment is given
OmniStem protocols use two main routes. Intravenous infusion delivers cells or exosomes through the bloodstream and takes about an hour. Targeted injections place the biologic in a joint, the spine, or the scalp. Some plans combine both, and your physician chooses the route, dose, and number of sessions after reviewing your records.
What a treatment plan involves
Treatment begins with a medical consultation, where our medical team reviews your history, current medications, and goals. Before treatment, you may receive guidance on medications and hydration. On treatment day, staff monitor you during and after administration.
Follow-up assessments track how you respond. Your physician adjusts recommendations from there.
What the evidence shows
Most of what is known about UC-MSCs and exosomes comes from laboratory and animal research, which has shown effects on inflammation and tissue repair. Human trials are smaller, and their results differ by condition; for many conditions the evidence comes from early-phase studies.
On safety, a 2021 meta-analysis of 62 randomized trials of MSC therapy linked treatment to transient fever, administration-site reactions, constipation, fatigue, and sleeplessness. Our physicians weigh this evidence for each case before recommending a protocol.
Start with a medical review
References
Arutyunyan I, Elchaninov A, Makarov A, Fatkhudinov T. Umbilical cord as prospective source for mesenchymal stem cell-based therapy. Stem Cells International. 2016;2016:6901286.
Caplan AI. Mesenchymal stem cells: time to change the name! Stem Cells Translational Medicine. 2017;6(6):1445-1451.
Kalluri R, LeBleu VS. The biology, function, and biomedical applications of exosomes. Science. 2020;367(6478):eaau6977.
Phinney DG, Pittenger MF. Concise review: MSC-derived exosomes for cell-free therapy. Stem Cells. 2017;35(4):851-858.
Wang Y, Yi H, Song Y. The safety of MSC therapy over the past 15 years: a meta-analysis. Stem Cell Research & Therapy. 2021;12:545.
