The human body contains a few hundred different cell types, from muscle and fat cells to liver and brain cells. These are called differentiated cells and their different shapes, sizes and function is influenced by the fact that these different cell types have different gene expression. Some genes (called housekeeping genes) are expressed in all cells, while some other genes are more highly expressed in some cell types than others. It is not all about genes, however, since cells are also influenced by other cells close to them and other external factors.
Before these cells became differentiated, they were stem cells. These cells are undifferentiated cells that can grow rapidly and become any of a large number of different cell types. There are different kinds of stem cells, typically divided into different classes based on their potential for differentiation. For instance, some stem cells can become a moderate number of different cell types (multipotent), whereas others can become any of a large array of cell types (pluripotent) or even any cell type in the body (totipotent). Other types of stem cells include adult stem cells and induced pluripotent stem cells (iPSCs). Read more about cell differentiation here and more about stem cells here.
Because stem cells can differentiate into different cell types, the general idea is that they might be used to replace things that do not work in the human body, from cell populations to tissues and even organs. The most common legitimate stem cell therapy in medicine involves using bone marrow stem cells (and chemotherapy) to treat leukemia and lymphoma. A small number of other legitimate therapeutic stem cell therapies have been shown to be effective in medical research and approved by regulators.
Yet, there are also fake stem cell treatments that are pushed by quacks that scam people for money and even causes serious harm.
What are fake stem cell treatments?
Like many high-tech science and medical areas, stem cells and stem cell therapies have been abused by quacks in a number of ways. They typically do not use stem cells to differentiate into mature cell types. Instead, some quacks push fake treatments that involve injecting stem cells directly into the blood. One problem with using embryonic stem cells in this extreme way is that they may run amok and create teratomas. These are uncontrolled growths that resemble cancer, but often feature differentiated cells, including bone, teeth, parts of the brain or even limbs. These fake treatments are not approved by the FDA. Some quacks claim that they are running clinical trials, but they are hardly ever approved by institutional review boards (IRBs). Needless to say, these fake stem cell therapies do not work and you cannot really rely on quacks to get the biomedical procedures right, so it might not even be stem cells that patients are getting injected with and it might be contaminated by harmful substances.
A group of quacks ran an alleged “clinical trial” (NCT02024269) testing stem cell therapy for age-related macular degeneration (AMD) that was registered on clinicaltrials.gov and approved by an IRB. This “clinical trial” was later withdrawn under unclear circumstances before patient enrollment had even begun.
In the future, it might be possible to make differentiated cells of the right type from pluripotent stem cells and use it to treat AMD, and there are currently over a dozen clinical trials all over the world registered at clinicaltrials.gov with FDA registration and IRB approval. Four of them are run in the U. S. (three if you do exclude this one). However, the medical research is not there just yet, and so there are no approved evidence-based stem cell treatments available for AMD.
Despite being withdrawn, the people behind the “clinical trial” manage to recruit a number of patients with AMD into their deceptive den. Using pseudoscientific methodologies, they concocted a mix between alleged “stem cells” derived from fat cells and blood plasma and injected it directly into the eyes of three elderly women who ended up more or less blind after the procedure. In a brief report published in the New England Journal of Medicine by Kuriyan and colleagues (2017), the patients were found to have gotten “severe visual loss”, which included too high pressure in the eye (ocular hypertension), bleeding retina (hemorrhagic retinopathy), bleeding into the eyeball (vitreous hemorrhage), retina detachment or lens dislocation. In other words, pretty severe damage to the eyes.
What was the details of the quack protocol?
The authors of the brief report in NEJM managed to get access to documents describing the procedure used to make the stuff that they injected into the three women. The reading is as chilling as it is bizarre.
Basically, they started by performed liposuction of the area around the navel under local anesthesia. Blood was also drawn from the patients and blood plasma rich in platelets was isolated. The material taken from the liposuction was subjected to a protocol that involved washing, enzyme treatment, shaking and centrifugation. After the final centrifugation, the material was resuspended in a few milliliters of plasma and then directly injected straight into both eyes of each patient. The brief report states that the adipose tissue was “processed to isolate the putative stem cells”, but it is unclear if there was anything done in addition to the above description.
This procedure does not do what the quacks claim that it does. There is no reason to suppose that this is an efficient method for isolating stem cells (and only stem cells) and there is nothing to suggest that this is safe to inject into the eyeballs of people. This is pseudoscientific quackery and dangerous bullshit.
The three patients found the “clinical trial” on clinicaltrials.gov, sincerely believed that it was an approved clinical trial and paid 5000 USD for it. However, the consent forms that were signed did not mention anything about a registered clinical trial or approval.
What did the authors conclude?
The authors suggest that the “stem cells” (if it really was stem cells) might have differentiated into myofibroblasts and caused the retinal detachment and proliferative vitreoretinopathy. At least one other symptom might be able to be explained by trypsin contamination of the injected material. This would mean that the quacks did not even perform their fake method correctly.
The authors concluded that “The patients paid for a procedure that had never been studied in a clinical trial, lacked sufficient safety data, and was performed in both eyes on the same day. Experimental bilateral intravitreal injections are
both atypical and unsafe.” Astonishingly, they even explain that some stem cell clinics claim that this kinds of injections cannot be regulated by the FDA.