Stem cell marketing is full of technical terms. This plain-language glossary explains the words you will meet in clinic brochures, consent forms and research papers — so you can ask better questions.
A · B · C · E · F · G · H · I · M · N · P · R · S · T · W
A
Adult stem cells
Unspecialised cells found in many tissues of the body (such as bone marrow or fat) that can renew themselves and make some of the specialised cells of their tissue. Also called somatic stem cells.
Allogeneic
Cells or tissue from a donor, rather than from the patient. Donor cells carry a risk of immune reactions and must be screened for infections.
Autologous
Cells taken from your own body and given back to you. Autologous treatments avoid rejection but still carry risks from harvesting and processing.
B
Bone marrow aspirate concentrate (BMAC)
Bone marrow drawn from the hip and spun to concentrate its cells. Stem cells make up only a tiny fraction of the cells in BMAC. Read more.
C
CD34+ cells
A marker used to identify blood-forming (haematopoietic) stem and progenitor cells — the cells used in bone marrow and cord blood transplants.
Clinical trial
A research study in people that tests whether a treatment is safe and effective. Legitimate trials are registered, ethically reviewed and rarely charge participants. Find trials.
Cord blood
Blood left in the umbilical cord and placenta after birth. It is rich in blood-forming stem cells and is an approved source for transplants for certain blood disorders. Cord blood guide.
E
Embryonic stem cells
Pluripotent stem cells derived from early-stage embryos. They can form any cell type and are used in research and a small number of clinical trials.
Exosomes
Tiny particles released by cells that carry proteins and genetic material. No exosome product is FDA-approved to treat any disease. Read more.
F
FDA “351” product
A cell or tissue product regulated as a drug or biologic, which needs clinical trials and FDA approval before it can be marketed. Most stem cell products sold by clinics fall into this group.
FDA “361” product
A cell or tissue product that is minimally manipulated and used for its normal (homologous) function, so it does not need FDA premarket approval. Clinics sometimes claim this status wrongly.
G
GMP (Good Manufacturing Practice)
Quality standards for producing medicines and cell products in controlled, inspected laboratories. Ask any clinic whether its cells are made in a GMP-certified facility.
Graft-versus-host disease (GvHD)
A complication of donor transplants in which the donor’s immune cells attack the patient’s body.
H
Haematopoietic stem cells (HSCs)
Blood-forming stem cells found in bone marrow, blood and cord blood. HSC transplants are the main established, approved form of stem cell therapy.
HSCT
Haematopoietic stem cell transplantation — a bone marrow, peripheral blood or cord blood transplant, used for blood cancers, some blood disorders and, in specialist centres, severe multiple sclerosis.
Homologous use
Using a tissue for the same basic function it performs in the body. It is one of the conditions for the FDA’s lighter “361” pathway.
I
IND (Investigational New Drug)
FDA permission to test an unapproved drug or biologic in people. Legitimate US stem cell trials of “351” products run under an IND.
Induced pluripotent stem cells (iPSCs)
Adult cells reprogrammed in the lab to behave like embryonic stem cells. Discovered in 2006, they are being tested for eye, heart and Parkinson’s disease. Read more.
Informed consent
Your written agreement to a treatment after being told its purpose, risks, alternatives and costs. It should never be rushed.
Intra-articular injection
An injection directly into a joint, such as the knee — the most common way clinics give orthopaedic stem cell treatments.
IV infusion
Giving cells through a vein. Most intravenously infused cells are trapped in the lungs within minutes. Read more.
M
Mesenchymal stem/stromal cells (MSCs)
Cells from bone marrow, fat, umbilical cord and other tissues that can form bone, cartilage and fat cells in the lab and release signalling molecules. Read more.
Minimal manipulation
Processing that does not change the original relevant characteristics of the cells or tissue. Culturing (growing) cells usually counts as more than minimal.
Multipotent
Able to become several, but not all, cell types — for example, blood-forming stem cells can make all blood cells but not nerve cells.
N
NCT number
The unique ID (e.g. NCT01234567) of a study registered on ClinicalTrials.gov. Use it to check any “trial” a clinic mentions.
P
Photobiomodulation
The use of red or near-infrared light to influence cell activity. It is the scientific basis claimed for red light therapy and light-based activation patches. Read more.
Placebo
An inactive treatment used in trials for comparison. Placebo-controlled trials are the best way to tell whether a treatment really works.
Platelet-rich plasma (PRP)
A concentrate of your own blood platelets, injected to deliver growth factors. PRP contains no stem cells. PRP vs stem cells.
Pluripotent
Able to become almost any cell type in the body, like embryonic stem cells and iPSCs.
Progenitor cells
Cells that are more specialised than stem cells and can make a limited number of cell types.
R
Regenerative medicine
A field of medicine aiming to repair or replace damaged cells, tissues or organs, using cells, biomaterials, genes or the body’s own healing processes.
Right to Try
US federal and state laws letting terminally ill patients request investigational drugs that have passed Phase 1 trials. Laws by state.
S
Stem cell activation
Approaches said to stimulate the body’s own stem cells rather than adding new cells — from exercise and fasting to light-based patches. Natural support guides.
Stromal vascular fraction (SVF)
A mix of cells taken from liposuctioned fat and processed with enzymes. US courts have treated SVF products as drugs needing FDA approval. Read more.
T
Totipotent
Able to form an entire organism, including the placenta. Only the fertilised egg and the very first cells after it are totipotent.
W
Wharton’s jelly
The gel-like tissue inside the umbilical cord, a common source of donor mesenchymal cells sold by clinics. Read more.
Before You Pay: The Stem Cell Clinic Checklist
- 20 questions every legitimate clinic should answer in writing
- A red-flag scorecard to spot unregulated marketing
- Realistic 2026 cost ranges: US, Mexico, Panama & Europe
- How to find a registered clinical trial
Last reviewed October 2026. For general information only — not medical advice. We do not endorse any clinic or product. Always consult a qualified, licensed healthcare professional. See our medical disclaimer and editorial policy.