Vatine et al. show that human iPSC-based modeling can pinpoint the origin of a neuronal disorder in the brain as a defect in transport of thyroid hormone across the blood-brain barrier, rather than in the neurons themselves.
Lim et al. show that HD iPSCs-derived brain microvascular endothelial cells have impaired angiogenic and barrier properties. Transcriptomic analysis provides mechanistic insights into pathways that underlie dysfunction, and WNT inhibition prevents angiogenic deficits. This system also suggests strategies to reduce disease burden and assess BBB penetration of drugs for HD.
Yesterday, a breaking news in the stem cell field came from a case report published in the New England Journal of Medicine (a respected journal in medical research) (http://www.nejm.org/doi/full/10.1056/NEJMoa1609583?query=featured_home).
What is probably the most intriguing about this case report from a stem cell clinic, that had a clinical trial submitted to the FDA and subsequently withdrawn in 2015 (https://clinicaltrials.gov/ct2/show/NCT02024269?term=NCT02024269&rank=1).
This case report focuses on three patients, elderly patients (70+) and all three suffering from age-related macular degeneration (AMD).
They all three being injected with mesenchymal stem cells. For those not familiar with stem cells, stem cells comes into different flavors depending on their origin and potency abilities. The most pluripotent type of stem cells are the embryonic stem cells (hESCs) that are derived from embryos. Following in their pluripotency comes in the induced pluripotent stem cells (iPSCs). Unlike hESCs, iPSCs are reprogrammed somatic cells (usually skin fibroblasts). Then we have bone marrow stem cells (from bone marrow) that have a narrower pluripotency but proven efficacious for treating patients with leukemia. Finally we have the mesenchymal stem cells (MSCs) obtained from the stream fraction of adipose tissue. Usually these cells are obtained by liposuction and isolated from the fat tissue via defined protocols.
Now this last type of cells has a certain classification that allows to use a loophole. In order to conduct a clinical trial, you have to submit an investigative new drug (IND) application to the Food & Drug Administration to show evidence of safety and efficacy from pre-clinical studies. These are safeguards that ensure patients and medical researchers enrolled in such trials.
Now, when you are dealing with MSCs, these stem cell “clinics” can exploit some loopholes and apply for a non-IND application if your trial follows two criteria: it is an autologous procedure (you are injecting cells from yourself back into your body) and there is no procedures that modify the material used (in that case, the purification steps are not altering the MSCs identity and function). In addition, these trials have to be done without any financial link. In academic institutions, you neither ask the patient to pay for the clinical trial nor provide the patient with a financial compensation (only a possible therapeutic outcome, if the treatment work). In this case reports, all patients paid $5000 to that clinic. it is also important to note a certain level of deception from the stem cell clinic as this registration at the ClinicalTrials.gov website appeared to these patients as a clinical trial were it was not. It is even mentioned by the authors of this case report that none of the consent form signed by these patients displayed “clinical trial”.
There is also report in the consent form that the patient were informed of the risk of blindness and were requesting to have the procedure done in both eyes.
These patients rapidly developed post-operative complication including retinal detachment, increased ocular pressure and hemorrhagic events, such complications were not taken care by the clinic involved in the stem cell procedure and were done in eye clinics in patients domicile.
By coincidence, NEJM also published another case report of the use of stem cells in AMD in a clinical trial in Japan (http://www.nejm.org/doi/full/10.1056/NEJMoa1608368?query=featured_home). This procedure was done using iPSCs from patients and derived into retinal pigmented epithelial cells (RPEs). These cells are lining the outer side of the retina and serve as a barrier for protecting the retinal neurons involved in vision. This is the famous “iPSC clinical trial” from Takahashi and colleagues that had to be halted due to some safety issues that were corrected (https://ipscell.com/2016/06/good-stem-cell-news-as-takahashi-ips-cell-trial-to-resume/).
So far, the encouraging part is the absence of post-operative complication and graft rejection and the patient showed an improvement in her vision.Yet, this is a single report and the authors were also very cautious about to make overstating conclusion.
These two cases report should inform into two things: we are making little steps but confident steps in stem cell based therapies but it is also important to raise awareness and vigilance about the methods of some stem cell clinics making unrealistic claims of stem cell therapies or posing as clinical trial center.
My recommendation is if you decide to jump into a clinical trial is to verify the affiliation of the center (avoid any private firms and check the credentials of any institution supporting this trial), ask your doctor to help you read through the consent form and never ever be asked to pay for the procedure. The trial is funded by research grants, if it is requested that you cover the expenses of such procedures run away!
This post is related to a recent testimony of Rhonda, a follower of my Facebook page, that asked me whether stem cells can cross the BBB. As a BBB and stem cell scientist, this was a very good question asked. If I have to tell my thought in a sentence, I would it’s complicated. To support my claim, I will use the recent review from Aylenik and colleagues (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4106911/) and Liu and colleagues (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3753739/)
First, it is important to remember the reader about what is a stem cell and what are the different types of stem cells. A stem cell is a particular type of undifferentiated cells capable of self-renewal and capable to differentiate into any cell type following the right molecular and environmental triggers.
In the scientific research, we have different types of human stem cells: we have firstly the pluripotent stem cells coming from embryos (human embryonic stem cells or hESCs) or from reprogrammed adult cells (induced pluripotent stem cells or iPSCs). These are the most used in basic research because they have the most potency to differentiate into any cell type. However these are also the type of stem cells that have the most important concerns in terms of safety as such undifferentiated cells rapidly develop aggressive tumors.
The second type of stem cells that are more in use in clinical research are stem cells derived from placental cord blood or from bone marrow (hematopoietic stem cells or HSCs) or from the stroll fraction of adipose tissue (mesenchymal stem cells or MSCs). These cells have a much less pluripotency as these cells are already engaged into a defined lineage. However this lineage restriction make these cells much less prone for developing tumors and are considered safe.
Now let’s get into the details. In this post, we will not talk about stem cell delivery that bypass the BBB such as intranasal, intrathecal or intracerebroventricular injections. We are discussing here about intra-arterial or intra-veinous injection of stem cells and their delivery across the BBB, in particular the delivery of MSCs across the BBB.
One interesting aspect of the MSCs delivery is their particular attraction to sites of injury, including inflammation sites as mentioned in Liu’s review. What we know is that MSCs can cross in vitro models of the BBB (cell culture models) but yet we have a very limited number of studies that have demonstrated similar approaches in animal models.
The mechanism by which such MSCs may cross the BBB appears to use similar keys used by leukocytes to infiltrate across the BBB but also may include a localized degradation of the basement membrane (a biological mesh lining blood vessels) to allow their infiltration. However, as mentioned by Liu in his review, early clinical trials have shown mixed if not negative results (see Ankrum J et al., Trends in Molecular Medicine 2009; Karp et al., Cell Stem Cells 2009).
Stem cell-based therapies have a important potential to improve regeneration following injury, but yet claims that such stem cells can cross the BBB remains weak and still needed to be demonstrated. Yet, a recent trend observed in the US and in other countries is the emergence of “stem cell clinics” and the subsequent “stem cell tourism”. Such clinics that operates on protocols not approved by the Food & Drug Administration and not published in peer-reviewed journals (to ensure their efficacy and reproducibility) often laud “miraculous claims”, promising patients to cure their diabetes, knee arthritis if not more serious neurological disorders including stroke, Alzheimer’s disease, autism spectrum disorders, lysosomal storage disorders, cerebral palsy or multiple sclerosis.
The main problem with these clinics is not only their claims are not based on science-based medicine, but also until now stem cell therapies in academic settings (including university hospitals) are still in their infancies (Phase I and IIA clinical trials), mostly focusing on the safety of such therapy before we can consider assessing their efficacy.
Such “therapies” are indeed very costly ($30’000+ price tags) but also the nature of such treatment remains shoddy and unclear. Worse, a recent case report recently published by the New England Journal of Medicine (http://www.nejm.org/doi/full/10.1056/NEJMc1600188) reported the case of the growth of a proliferative lesion on the spinal cord of a patient that underwent such “stem cell therapy” following a stroke injury. Indeed, a recent opinion letters written by Turner and Knoepfler in Cell Stem Cell discuss more deeply more about such recent phenomenon (http://www.cell.com/cell-stem-cell/fulltext/S1934-5909(16)30157-6).
In conclusion, stem cell therapies have shown interesting potentials in pre-clinical models and early stages of stem cell therapies are providing optimistic news about the use of certain stem cells to assess their clinical efficacy in a rigorous and reproducible experimental paradigm, especially for aiming to treat neurological diseases.
However, the delivery of such cells remains an important challenge with a weak literature to support the claim that such cells can cross the BBB once injected via IV route.
In addition, because stem cells have an important potential, a recent rise in stem cell clinics promoting unproven treatments raises questions of safety and concern for vulnerable patients to what appears to me as a rise of a new generation of “snake-oil sellers”.
One of biggest danger facing the stem cell field is the proliferation of “stem cell clinics” inside and outside the United States promising miracle cures for any neurological diseases. The problem with this “stem cell tourism” is not only the huge financial investment into a medical procedure that has yet to filter through scientific rigor and clinical efficacy (at this time, we are still at the stage to assess if these procedures are safe), it is also the risk of developping post-operative complications with “worst case scenarios” happening often, in particular growth of tumor. This is what happened to a stroke patient that not only did not see his stroke injury recovered but now has to fight off the grow of a tumor inside his brain.
Neurology Today discuss the case of this patient, with the intervention of different experts explaining the current state of stem cell clinical trials and the danger of stem cell tourism.
Waking up this morning with a “stunning” finding about the recent publication of a study by Stanford researchers that noted the improved outcome in stroke patients following injection of stem cells have been positively headlined in the fairly serious “Washington Post” journal.
As a neuroscientist and stroke researcher, this sounds like a very good news because there are not much good news when we discuss stroke clinical trials that show something better than placebos. But also me and others like Pr. Paul Knoepfler as he rightly wrote in his blog post to not fail into overhyping and overselling a pilot study and by the way promising the moon to patients and come back to them with a disappointing news.
I thought it would be a great idea to discuss a bit more about this paper, its observations and outcomes and current limitations.
1. What is the study that was has been cited in the Washington Post and how does it stand in terms of scientific publication?
According to the Washington Post, this study has been published in Stroke journal and authored by Gary Steinberg, MD-PhD (Stanford University) listed as leading author. Based on the information, we are likely referring to the following article. I have attached a screenshot of the abstract page from the journal website:
First thing, is to classify the authorship ranking. Dr. Gary Steinberg is what we refer as the primary author, usually the person that has performed most of the experiments and analyzed the data. On the other hand, we have Dr. Neil E. Schwartz as a senior author. It is usually the one that has the first thought process, planned the experimental design, wrote and finalized the manuscript and usually the one that have put the money on the table (the funding awardee) to run this study. Here, I would argue that we have a difference in what we consider as the lead author of the paper. I would consider Dr.Schwartz as the lead author due to the ranking, but thats some science bickering.
The paper got published in Stroke, that is the flagship journal of the American Stroke Association (a subdivision of the American Heart Association). Being published in a society journal is a good step but in case not enough to justify the overhyping. Why? Impact factor. Impact factor matters. Stroke, according to the American Heart Association, has an impact factor of 5.76. Thats good but a clinical paper can get better rating. For instance, Circulation (the highest-ranked AHA journal) is listed with an IF~15, whereas Nature Medicine (a mastodon for high-impact translational studies) has an IF of 27.
The paper is surely good, but does it qualify for the “stunning” adjective? Certainly not and the overselling of it is not justified by the publication metric.
Also note the title, this is a Phase I, IIa. So it means it is very a early stage of the clinical trial. Phase I in the first stage of clinical trial in which we test the safety of a novel treatment, Phase IIa is to try if there is any efficacy in a very small subset of patients (less than 50). Again, at this stage, it is a dangerous step to oversell something that yet to show efficacy with hundreds of patients.
2. What does the paper says?
The paper is behind paywall so I cannot publish any figures and text. The paper got one round of revision, as it was received in February 9, revised in April 1 and accepted in April 26. If we consider a 4-6 weeks turnover between the time you submit your draft and the editor respond to you with reviewer comments, we can speculate that the revision was minimal and quickly addressed by the author.
This study rely on using mesenchymal stem cells (MSCs) in a small cohortof patient. The study uses a particular type of MSC, the SB623 bone marrow MSC cell line.
MSCs are a particular type of stem cells. They have the least pluripotency because they have already been engaged inside a differentiation (to make it simple, they are programmed to give rise to blood cells such as white blood cells, red blood cells or platelets) and therefore have little opportunity to be re-wired to form neurons or cardiac cells. However, because they are already into a certain differentiation stage, these cells are considered as the safest for implantation. Other stem cells (such as embryonic or induced pluripotent stem cells) are nefariously known to wreck havoc if injected as undifferentiated (they cause what we call teratomas), safety of differentiated precursor cells (such as neural precursor cells) remains to be addressed. Thats also alleviate the issue encountered with previous stem cell therapy based studies that consisted as injecting a mixture of bone-marrow stem cells without knowing exactly which sub-population is carrying the protective effect. Interestingly, these MSCs carry a plasmid allowing the overexertion of a protein called Notch-1 intracellular domain (ICD). Notch-1 ICD is a fragment of the full Notch-1, that is cleaved by certain enzymes. Such ICD can therefore act as a messenger inside the cell and exert some biological activity.
The study used three doses of cells and were directly injected around the site of infarct (peri-infarct area). In stroke injury, we have the core or infarct area that is considered as the ground zero. We consider it as the necrotic area or the wasteland zone. Everything inside is dead and highly hostile for repopulation. However, the peri-infarct surrounding this zone is battling for days and weeks, torn between signals telling neurons to survive the injury from signals telling neurons to die. This fine balance is one target for therapies as we consider finding factors that can title neurons in favor of survival can help them recover and minimize the loss done by the stroke injury.
What is interesting is that these MSCs have been shown to only survive for one month. Thats a good point for the safety issue. In this cohort of patients (18 in total), very few side effects were noted suggesting a fairly safe method for up to 12 months. However, one caveat of this study is the lack of proper control or placebo.
3. Why this study has been overhyped and oversold by the WaPo?
All patients improved over the 12 months period compared to their initial timepoint (the day after stroke injury). Furthermore, all three doses have been pooled together, so we cannot tell if there is a better recovery with a higher number of cells. This is a serious concern that has to be mentioned: we cannot tell if these patient recovered by their own or due to the treatment.
If we had a placebo group, we could have been able to compare and contrast the gain due to the stem cell treatment. We also cannot see how each individual and each group have been recovering. It would be interesting to see how age and sex (male/female) played a role in the recovery.
This is the sin of mainstream news media: they have again sinned in overselling a study that is interesting but still lacking solid evidence to sell that case. The study and approach is interesting but the version sold in the news is a far-stretched version of where the study actual said. Selling it as “stunning” is not only wrong and inappropriate, it is also a dangerous move that will serve some for-profit stem cell clinics to make profits on patients that have been experiencing stroke and despairingly looking for a “miracle cure”.
I am sure that everyone heard about that clickbait headlines that run over on social media, with viral posts and videos proposed by a company named “Bioquark” (US) in association with another company named “Revita Life Sciences” (India). Among some websites that have reported that information, I decided to share the article posted by Futurism earlier this week:
Of course, my first reaction was surprise and shock. Surprised because no one came as far to make a claim on resurrecting dead people. Oh well, not surprised if you look at fictions they only time I heard people resurrecting dead were with various methods including electrical energy (Frankenstein’s Monster), trioxin 245 (Return of the living dead), cybernetic implants (Robocop) or some classified scientific methods codenamed “Lazarus project” (Mass Effect 2).
Because with extraordinary claims comes extraordinary proof and evidence. Usually this does not end up very well and usually ends up flat like an underbaked souffle. Just see the epilogue of Theranos and remind yourself to never sell the bears hide before killing it.
What is being “brain dead”?
Brain death is defined according to the Merck Manual by “a loss of function of the entire cerebrum and brain stem, resulting in coma, no spontaneous respiration, and loss of all brain stem reflexes. Spinal reflexes, including deep tendon, plantar flexion, and withdrawal reflexes, may remain. Recovery does not occur.” (source: http://www.merckmanuals.com/professional/neurologic-disorders/coma-and-impaired-consciousness/brain-death).
This definition is very important as it is inclusive of both absence of cortical function as well as vegetative functions emanating from the brain stem. Brain stem is an important nervous structure that controls all the vegetative functions including control of the respiration, bowel movements, blood pressure, pH and smooth muscles activity. When a patient in such condition, this is a point of no-return. There is virtually no chances patient recover. The patient seems alive because the patient is on respiratory aid and still has the heart beating. The heart will keep pumping as long it is properly perfused with oxygen and nutrient.
One test to assess the brain status of a patient in comatose stage is to assess its ability to breath by its own. This is what we refer the apnea test. The human body is designed that it will by survival reflex induces breathing even when we force apnea. In these patients, the loss of brain stem viability will fail to induce this respiratory reflex.
In the case of this news, we will have to look at the application packet submitted to the NIH clinicaltrials.gov portal that can be consulted here.
According to the application, the companies have in their inclusion criteria:
Individuals declared Brain dead from a traumatic brain injury having diffuse axonal injury on MRI Not willing for organ donation
Written informed consent from the legally acceptable representative of the patient
This is an important criteria for ethical standpoint, because these volunteers fall into the uniform anatomical gift act (http://www.uniformlaws.org/shared/docs/anatomical_gift/uaga_final_aug09.pdf).
Because they can considered as anatomical gift, there is little or no of the ethical issues commonly raised with living and healthy patients, that require absolutely an institutional review board (IRB).
In the press release, the company or companies as it involves Bioquark and Revita Life Sciences claim they receive approvals from the Institutional Review Boards and by the National Institute of Health to perform their experiments on volunteers that donated their bodies to science and that refused to sign as potential organ donors.
It is also important to note this trial will be performed outside the United States, especially held into the Anupam Hospital, Rudrapur City, Uttrakarand State in India (based on the email address of the collaborator listed on the trial).
This is an important issue to raise, as we have these trials performed in India. India has currently a fairly laziest policy in terms of ethics in biomedical research as raised recently by an article in the World Health Organization (WHO) referenced here: http://www.who.int/bulletin/volumes/86/8/08-010808/en/.
Although running experiment on clinical dead persons is by itself not an ethical violation as long as the body is utilized and treated following medical and ethical consideration, we cannot however fully guarantee that these donors and their relatives have provided their consent into a fully informed and without any financial incentives.
What is the science behind the trial?
The second issue that I have with this study is the science behind it. In their application, the authors listed the outcomes as the following:
Primary Outcome Measures:
- Reversal of brain death as noted in clinical examination or EEG [ Time Frame: 15 days ] [ Designated as safety issue: No ]
Secondary Outcome Measures:
- Cerebrospinal fluid (CSF) analysis of color consistency, cell counts, and microbial evaluation [ Time Frame: 15 days ] [ Designated as safety issue: Yes ]
To signify any signs of aseptic or bacterial meningitis
- MRI analysis to analyze any changes in meninges [ Time Frame: 15 days ] [ Designated as safety issue: Yes ]
To signify any signs of aseptic or bacterial meningitis
- Pulse [ Time Frame: 15 days ] [ Designated as safety issue: No ]
- O2 saturation [ Time Frame: 15 days ] [ Designated as safety issue: No ]
- Blood Pressure [ Time Frame: 15 days ] [ Designated as safety issue: No ]
- Respiration changes [ Time Frame: 15 days ] [ Designated as safety issue: No ]
The idea of resurrection the clinical dead and the reality of the experiment is way different and definitely less eye-catching and sensationalized. The paradigm consist of implementing stem cells inside the brain and assess the presence of a re-establishemnt of an electrical activity as measured by an EEG.
Several studies has documented protocols to differentiate human pluripotent stem cells (including embryonic and induced pluripotent stem cells) into neurons capable of physiological activity, in other terms of capable to general an action potential or in other words electrical activity.
The first issue I have in this case, where, when and what of stem cells will be used are never mentioned, either on the press release or on Bioquark Inc. presentation slide.
The second issue I have is about the credentials of the investigators, Dr. Himanshu Bansal. By submitting a query on Pubmed with the keyword “Bansal H Stem“, we have only four results listed with two directly relevant studies published in the Journal of Stem Cells. Such journal is published by Nova Science Publishers, a predatory publisher as reported by Scholarly Open Access. Add to it there is no Thomson-Reuters ISI impact factor listed raise the question is this journal is legitimate or will publish anything as long as you give them a valid credit card number. Remember the adage “garbage in, garbage out”
Things are even more murky when you visit Dr. Himanshu Bansal webpage and the tab about his stem cell results. For information, this is a screenshot of the page:
This is fairly impressive yet highly questionable when someone boast such claims without linking to the literature, considering that until now there is NO FDA approval for stem cell treatment.
If it looks like a quack and sounds like a quack
Now things are getting suddenly sour and fishy. The more we dive in and the more things are looking. Now one criteria I consider important for assessing a reliability of a startup biotech is its portfolio and if not the quality of the data presented. This is not looking good either.
Unfortunately, Bioquark has little to show and have rather laconic statements, no published studies, no data demonstrating the activity of their drug candidates nothing. For my standpoint, I am always skeptical when I see a biotech company making a living on cosmetic and beauty products, as seen on their page:
This is raising already some issues about the company credential, I am not even talking about Revita Life Sciences. Both company have such a horrible web design but also looks a lot like websites I commonly label as “quackery”, especially the second website. Having on the frontage treatment like “Naturopathy, Bioactive Molecules, Laser Stimulation, Ayurveda….”. If it sounds like a quack and looks like a quack…..
Now, if you pay attention to the Slideshare, the quality of the data is simply horrible and just look like a botched data. One thing that particularly caught my eye was this slide:
The gold standard in cancer research using mouse models is the xenograft model in which you inject sub-cutaneously human cancer cell line and follow the growth of the tumor like in this study.
In their study, rationale of injection of tumor in the paw is never mentioned, not even mentioning the questionable quality of the pictures, with the identification number changing over time in terms of quality. Indeed the paw seems to display an edema as shown in an another study. Edema is a swelling of connective tissue due to various reasons. In that case, I question whether the authors injected some vital dye (Trypan blue or Evan’s blue) into the paw with a volume enough to induce an edema and allow it to resorb over time, as seen in a study found online.
If I was an investor at this point, I would run away from this project.
To conclude on this breaking news that has its weight of clickbait, I sincerely raise questions and skepticism on that study that boast to revigorate patients that are clinically dead. There are a lots of smoke screen, an outcome that is very limited with very or little significance in terms of science. Here are my major concerns about that experiment:
1. There are no data from preclinical studies done in animal models to support the information proposed for the clinical studies. This is contradicting the common scientific process in which we transition from the bench to the bedsides.
2. The outcome measured as proposed in the NIH application package is much less extraordinary that the claim posted on mainstream media. That is fine but really raises the relevance of this study. Stem cells may be able to survive and differentiate in the brain parenchyma to an extent they can generate electrical activity measurable by EEG. However, there is virtually no chances these cells will provide an axon rewiring capable to result in functional activity. So no zombies.
3. There is a lot of smoke screen in terms of the experimental paradigms. We don’t know which stem cells will be used, where such stem cells will be implanted and how they will address the outcomes beyond the EEG. It sounds impressive in terms of science but once we think on how this advance our current knowledge, we are dropping short. We are ending up with a similar outcome than Dr. Frankenstein monster: it sounds very impressive and defying but the relevance of the monster was virtually none.
4. Finally, the public data and the lack of credentials of both companies and the investigators in terms of experimental data, peer-reviewed studies quality and records and the tendency of both companies to rely on healthcare products if not on alternative medicine as a source of revenue is sincerely raising questions on the ability of these companies to deliver. In particular, some claims of therapeutical success of Dr. Bansal on treating neurological diseases using stem cells are highly questionable as there is until now no evidence or approval by the FDA for any stem cell treatment beyond bone marrow stem cell transplants for patients suffering from leukemia.