The Coming of Age of Pluripotent Science & Musings on a Sonogram

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One of the most memorable images I can recall on the effect of catalytic dynamics for me during these years of scientific curiosity was the explosive result of sperm enzyme successfully impacting a human egg - almost Big Bang like in all its microscopic potential.

One can now extend that impact phenomena analogy to the very pertinent research and translational effect Induced Pluripotent Stem Cell (iPSC) technology has had on the field of molecular biology and regenerative medicine.

Nature - Andy Potts

It’s been ten years since Shinya Yamanaka and Kazutoshi Takahashi opened the portal to a whole new way of thinking and practicing the Art of Stem Cell Science by announcing that embryonic like properties could be regained in adult cells through molecular reprogramming.

Royal Society

Much has been written about this apex moment of foundational innovation which ushered in the era of mainstream adoption of reverse engineering techniques on human cells but as we celebrate the ten year anniversary of iPSCs the opportunity presents itself to reflect and celebrate the coming age of Pluripotent science, specifically iPSCs.

Signals of Canada, a leading destination for "insiders’ perspectives on the world of regenerative medicine and stem cell research, written by scientists and professionals in the field" is hosting a "Blog Carnival" of which this article is one of a number being written covering the iPSC anniversary topic. Please click here to read what other bloggers think.

Inherently complex the various Pluripotent states and the multitude of their progressively differentiated descendants, as they relate to human biological microsystems, have only begun to be explored and understood. The inherent processes by which these interconnected derivative cells work and communicate are by and large just now being decoded and mapped. Although it’s been only ten years since the discovery of iPSCs and nearly 20 years since the human embryonic stem cells were first isolated the progress made to-date in translating Pluripotent science into real world clinical programs is very much the focus now of countless labs in the field, thanks in large part to the advent of “open source” iPSC technology. 

Prior to iPSCs the use of hESCs and the technology associated with its clinical translation was largely a specialty area limited in scope by funding, rules, regulations and IP. The advent of iPSCs changed that and with it the stem cell industry added a universal layer of potential. Whether it be using Pluripotent derived cells as tools or more notably to develop therapeutic cell candidates for clinical use those researching and developing applications using these cells are pioneering the way forward for the emerging era of next generation stem cell products.

To put not too fine a point on it, we have only scratched the surface and in the next ten years I expect there will be a number of Pluripotent treatments on the market in various countries and many many more still in the clinic moving towards approval with positive results over standard of care or filling-in where there is currently nothing to offer patients in need.

The topic of what can we expect to see on the frontline of the developing therapeutic market using Pluripotent derived cell products is often highlighted as a discussion point and rightly so given the limited public depth of awareness on the subject and the long standing promise by the sector as a potential basis for effective treatments.

Below are some of the targets and iPSC programs representative of the state of play in the field to look out for:

TARGET - COMPANY/INSTITUTION - LEAD SCIENTIST(S) - CELL -  DISEASE - AUTO/ALLO*
EYE
Riken/Healios		Masayo Takahashi		iRPE++	Wet/Dry AMD++	Auto>Allo
Notes: Program will address many disease states of Retina/Eye
Astellas RegMed		Lanza/MacLaren		iRNP++	Dry AMD/RP++	Allo
Notes: Program will address many disease states of Retina/Eye
UWisconsin Waisman		Gamm/Meyer		iRNP/RPE	Stargardt+	Allo
Notes: Representative of next gen concept using eye "organoids"
NEI/CDI-Fuji		Bharti/Miller		iRPE	Dry AMD	Auto
Notes: US Govt backed program
Cedars Sinai/CIRM		Shaomei Wang		iRNP	RP	Allo
Notes: Advanced status w/ IND enabling studies
BRAIN
Kyoto Univ		Jun Takahashi		iNC	Pakinsons	Allo
Notes: Leading iPSC Parkinson program due to start in 2017
Sloan Kettering		Lorenz Studer		eNC/iNC	Pakinsons	Allo
Notes: Top tier US hESC/iPSC lab moving to clinic
Scripps/CIRM		Jeanne Loring		iNC	Pakinsons	Auto
Notes: Bringing it home full circle w/ CIRM onboard
IMMUNE
Cynata		Slukvin/U Wisconsin		iMSC	GvHD++	Allo
Notes: Entering clinic later in 2016 w/ solid pre-clinical data
Astellas RegMed		Robert Lanza		iMSC	Sepsis, Lupus++	Allo
Notes: Multiple targets across board w/ pre-clinical hPSC data
BLOOD
Megakaryon-Kyoto/Tokyo+		Eto/Nakauchi/Daley		iPlatelets	Cancer/Surgery++	Allo
Notes: Leading Japanese program poised to enter clinic in 2017
Novosang-Roslin/SNBTS++		Marc Turner		iRBC	Thalassaemia++	Allo
Notes: Leading UK Consortia looking to clinic in 2017
Inserm/PlatOD		Dominique Baruch		iPlatelets	Cancer/Surgery++	Allo
Notes: Leading French program nearing clinic in 2017
Astellas RegMed		Robert Lanza		iPlatelets	Cancer/Surgery++	Allo
Notes: Had a leading program using research grade iPSC line in 2013
Players in CAR/Immuno Space				iBloodCells	Cancer/Immune	Auto>Allo
Notes: Auto/Allo B, T, NK, DC+ benefits 4 immuno product requirements

*The above listing is representative of the sector and is not at all comprehensive. Apologies to the many great programs that should be there also.

hiPSC science has industry wide support globally and is a mainstream technology acceptable in jurisdictions in which other ES methods face challenges. Translational hurdles for hiPSC are specific to their reprogramming and to the adult to youthful conversion which forms the basis of the applied technology. This presents an additional safety component to the already strict regulatory oversight applied to the clinical translation of Pluripotent programs now and in the future. 

Will they be highly successful and achieve revolutionary paradigm shifting status and establish new standards of care in their go-to-market quests? 

That is a subjective question for each and every program and one which you could speculate on, yet it would be Hype to suggest definitively without established patient data. However, the indicative MOA and technology basis of those programs on the list point to a sound foundation to work from. 

In my opinion, Pluripotent science, specifically hiPSCs as a universal technology, has the very best chance to score across the board wins for the patient in areas of unmet medical needs. 

Why? 

Some of the reasons I have doggedly believed that lie in the very nature of the plasticity of the sources, youthful phenotypes, cell expression and innate modulatory properties. Other reasons specifically relate to the field’s capacity to precisely derive and modify them in-vitro while perfecting their required derivative purities and expandability to consistently replicate them indefinitely in volume under strict quality control for regulated mass market applications. 

This potential, if successfully delivered together, will usher in a new Pluripotent Era in the Stem Cell Story. 

Commentary

Are we at an inflection point?

pavasoni

Certainly the perceived slow pace of translational activities has been a media drag on the sector, irrespective of the actual comparative timelines to move from bench to bedside. In retrospect there are still only a surprisingly small number of clinical programs in trials worldwide using Pluripotent derived cells, due in large part to stricter preclinical and regulatory standards applied to safety issues associated with these cell sources. So one would say we’re definitely due some momentum building inflection points….  

Human embryonic stem cell trials were initiated in the US some 6 years ago on the basis of only research cell lines after lengthy preclinical research and safety checks. Subsequent small studies in Europe and Korea using hESCs added additional safety data. These trials paved the way for iPSCs yet still today the only enrolled clinical trial for iPSC derived therapeutics is in Japan. This pioneering trial had been on hold for over a year as the cell source analysis flagged possible genetic instability issues and was switched out from an autologous approach to a recently approved allogeneic cell line and is due to resume in 2017. The one patient to-date receiving the iPSC based iRPE cell sheet for Wet AMD has been reported to be in good condition with no apparent safety issues associated with her procedure.

The rigorous standards of the need to use an NIH approved clinical grade cell line in the US has delayed the start of US trials on iPSCs and only just recently has one been announced as available. Pre-clinical lab work one would assume would now need to be done using that line for the clinical trial programs wishing to enter the clinic sometime in the future (yrs) or approval sought and granted for proprietary lines already used for clinical prep on existing developmental programs. This safety issue, albeit necessary and prudent, has forestalled the advancement of Western work and raised the bar from where hESCs entered the clinic.

When discussing timelines and where this segment of the sector is headed it’s important to factor in these types of regulatory hurdles one must overcome on the road to a Pluripotent IND, clinical trial approval and human phased testing. Trial design considerations require stringent oversight monitoring of Pluripotent trials and have and will slow down the translational best efforts of those academic and commercial players entering the space.

Generally if it takes longer that the average drug development process to see stem cell based products enter trials and progress through the Phases and a therapeutic emerge from any stem cell specific regulatory approval pathway people will continue to be disappointed. A scaled approach to the sector’s product entry and exit criteria seems reasonable given the variance of risks associated with different stem cell products under some form of adaptive umbrella.

Safety is of the essence and the nascent SC sector requires everyone err on the side of caution. This is the mantra I hear regularly and I can’t really say it’s not appropriate to a great extent. However, it is this writer’s opinion that the priority should not be overly weighted towards the slowest approach to protect the sector at the expense of patients willing to engage in regulated, open and comprehensive phase development programs designed to enroll and prove the science. Sufficient data can only be generated from a participatory system that is adaptive and accommodating not restrictive and burdensome by design or intent.

A Quad Pregnancy demands care & attention.

lifesitenews

Ashley Gardner Quad IVF Reaction cnn

When I recently scanned the Pluripotent sonogram I saw some Art where 4 heads appeared! Unlike our shock horror double take when 2 appeared in my wife’s scan, I was glad to see the 4 represented there, happily squished together and well. One seems to be growing bigger at the expense of a couple of the others but by and large it’s a Bridge Gang willing and able to take on the challenges when alive and kickin. I personally look forward to seeing them all born healthy and grow, in addition to their Olympic caliber Adult cousins. That would give us semi-oldies the best chance when it´s our turn to ask for help from those wise and experienced in the Jedi ways of healing. This is where Advocacy for Cures comes in. 

buzzfeed

Hope is a powerful force and will always be there for patients in need. Unfortunately the reality is that most next generation Pluripotent cell solutions are still a few steps away, if not more, for those that suffer. High science, low science, no science - too many people continue to be excluded, lack alternatives, suffer & die from disease. Stem Cell Science offers potential solutions and requires stakeholders to rally around programs and data that deliver real world results, even marginal benefits over existing options while awaiting more advanced solutions.

To conclude I have reported on the stem cell industry, specifically the Pluripotent segment for many years, and it has been easily influenced by sentiment and competitive currents rather than sharpening its aim on achieving sector growth. What we all care about most are real solutions for the long list of conditions that continue to ail us and for those that we love. Rather than future technology leading, current programs built on the foundation of pioneering efforts in both the Adult and Pluripotent fields need to be clinically accessible and then successfully delivered widely. Supporting and driving all safe and effective stem cell solutions will propel the entire sector forward.

Safety with pace, open and inclusive. Driving patient centric solutions forward as a community, in a modernized regulatory environment, by design and for the people.

Advocacy for Cures. 

Cheers



Refs:

Cell Press Nucleus - "iPSCs: A Decade of Discovery" (comprehensive review issue)

Cell Stem Cell Editorial: "10 Questions: Clinical Outlook for iPSCs" Cell Stem Cell, Vol 18, Issue 2, 170-173, DOI: 10.1016/j.stem.2016.01.023 (included in review issue ref above)

Ilic, D. and Ogilvie, C. (2016), "Human Embryonic Stem Cells — What Have We Done? What Are We Doing? Where Are We Going?". Stem Cells. doi:10.1002/stem.2450

The Niche, P.Knoepfler: "Yamanaka's baby turns 10 so here's a top 10 list of IPS cell hot button bullet points"  

Balancing Paradigms with Mesenchymal Stromal Cells

Steve Gschmeissner/Science Photo Library

Innovation isn't uniquely devoid of commonality of adoption by discipline. Rather the likelihood of acceptance generally tracks evenly to historical norms in parallel with society's openness to progress and the search for solutions. However, the impact of technological change is variable and dependent on societal factors related to income and health. One could argue the greatest benefit comes when change drives both economic prosperity and improved health standards.   

While the average pace of technological innovation slowed some decades ago the recent rapid rise of medical science has taken on the mantle of sustainability for growth. The dramatic impact potential of fundamentally transformative practices in healthcare is being fueled by access to new knowledge and a greater sharing of insight. 

Today, due to the convergence of various technology led disciplines, there are many important catalysts for paradigm shifting change. A key criteria common to all are the Drivers - fundamental products or processes that opens up the gates to new realms of understanding and acceptance. At each juncture a bridge must span the divide and a stake ground into new terrain. 

Are MSCs a Driver that can forge a paradigm shift in stem cell healthcare & how did we get here?
         

The investigation of bone marrow (“BM”) stem cells led to the establishment and widespread clinical practice using cells of the mesodermal blood lineage via bone marrow transplantation – known as hematopoietic cells (“HSCs”).

The first use of these BM  stem cells as therapy was pioneered over 50 years ago when transplants were first introduced experimentally to treat leukemia. However, as with most donor tissue the understanding of immune rejection of foreign non-self cells was and still is of major concern for the successful treatment of disease using allogeneic (donor) tissue. This is even the case when immuno-histocompatibility is done via matching of the cells to the host. This complication has stymied the field of cellular therapeutics due to the severe adverse events that can result from the administration of donor derived cellular treatments. In the case of BM transplantation they routinely cause Graft versus Host Disease (“GvHD”) as a result of the treatment, with approximately 50% of all such patients reporting complications. The percentage of mortality as a result of this last resort treatment intervention even today is staggering with up to 17% of all severe liver/gut GvHD cases resulting in death(1).

NIH.gov

As a field the discovery and isolation of Mesenchymal Stromal Cells (“MSCs”), a small subset of BM niches representing less than 0.01% of all HSCs, was a watershed moment. It was a true breakthrough as these cells were found to be able to replicate as multipotent precursors and can be differentiated into fat, bone and cartilage. The isolation and clonal nature of these MSCs opened up a whole new avenue for cellular investigation. Further sources of MSCs were discovered in a range of bodily tissues, including fat, perinatal tissue and dental pulp. The technology for human application of these adult cells gave rise to the stem cell industry we know today. Upwards of 500+ clinical trials using MSCs are registered currently in the US central database clincaltrial.gov for a variety of unmet disease indications (2).

In addition, there is a large growing trend of undocumented cases using MSC products in private medical offices as marketed treatments via autologous (self-to-self) therapies (3). These unlicensed medical practitioners using MSCs products are the subject of considerable debate as to where the line should be drawn between required regulatory oversight and freedom of medical use in private clinics for autologous treatments. The US FDA is currently reviewing draft guidelines (4,5,6,7) for treatment products using MSCs. They are preparing to define what constitutes more than minimal manipulation and cell use parameters. This is with a view to determining clinical trial requirements for MSC biologics, in keeping with current drug development procedures already in place.

Safe and Effective?   

The prospect of MSC utility for therapeutics has been due in large part to the evident immunological privileged nature of MSCs and their potential for universal application without immunosuppressive drugs – unlike HSCs themselves. Although MSCs have an antigen profile they lack major class antigens which makes them relatively immune-privileged to the host system thereby allowing for donor derived cell treatments without treatment rejection in low dose regimes.      

The Scientist - Keith Kasnot

The properties of MSC have been appropriately described as “ambulatory” and “paramedic” – i.e. they’re built to respond to injury in the body and assist in its repair. How they detect, migrate and signal, in addition to what biological manner they act, and what way in different circumstances, is a source of considerable study. It seems clear though now that their “method of action” (“MOA”) is modulatory in nature via complex regulatory mechanisms (8). One such mechanistic attribute is via the excretion of bioactive factors (vesicles, exosomes et al) and work to facilitate cell to cell communication networks (9).

Much has been written about the potential of tissue derived MSCs as a treatment option for a host of acute, immune and degenerative conditions. However, the field is still developing and protocols are being tested and adjusted to maximize possible outcomes. I’ve added an overview video below on the challenges and issues faced by MSCs product developers’ to-date by a leading expert in the field Dr. Jacques Galipeau of Emory University. The presentation highlights a number of findings on research and data in this sector and is well worth watching

Dr. Jacques Galipeau of Emory University

As mentioned, and referred to in the video, numerous clinical studies are underway on the use of MSCs and case reports have been published on both the potential benefits and in certain cases a lack of statistical benefit in patients receiving these cells from a variety of tissue sources.

With regard to the clinical trial results there is clear validation of MSCs safety profile, which is fundamental to their successful translation. Potential treatment efficacy of MSCs is suggestive to-date of positive activity on various outcome measures in a number of reported studies. These positive results are counter-balanced with questions on method of action (“MOA”) and some failed studies. This somewhat mixed picture generally points to issues relating to the development of medicinal products and cellular biologics should be viewed as no different.

A few of the better known company examples of MSC sector developments in the sector are briefly summarized below with links to the company for further details on the data.

• TiGenix (adipose/fat) – has moved on from the 1st EU approved and marketed autologous (“auto”) MSC cell therapy called ChrondroCelect for cartilage repair to an allogeneic (“allo”) product strategy with solid Phase III results in hand for Cx601 in Crohn’s Disease. This will mark their first allo indication nearing approval with other adipose stem cell products in the pipeline. 

• Mesoblast (BM) – bought the first approved western auto cell therapy Prochymal for GvHD from Osiris which had mixed results and was never released. They are developing a full in-house line-up of allo product candidates with good support data and are partnered with a Teva Pharma. Notable pipeline news include marketing approval of TemCell in Japan for GvHD with local partner JCR Pharma (repackaged Osiris product) and solid data in late stage trials (MSC-100-IV for GvHD also, MPC-150-IM for heart and MPC-06-ID for back pain, amongst others).

• Athersys (BM) – lost Pfizer as a program partner for MultiStem after releasing mediocre data in ulcerative colitis. A second Phase II read-out, this time in stroke, also failed to meet endpoints. However, newly released interim data in its ongoing stroke study is now suggestive of positive results from the homing-in strategy on potential earlier treatment window benefit. Also of note are the additional clinical programs in development for cardiovascular and inflammatory/immune indications. In addition there’s a solid validation deal with Healios of Japan for MultiStem in that market and use of the product for Healios’ ongoing development programs.

• Pluristem (placenta) – “PLX” product line for vascular, muscular and immune indications in early stage clinical trials (PI & PII) with solid data in muscle and critical limb ischemia. Promising preclinical results for bone marrow repair with government sponsorship for rapid route to market in acute radiation syndrome.

• 
  Vericel (BM for heart program) – previously known as Aastrom with a long history of development of auto MSCs for heart and CLI indications with poor accumulated data continues to develop the heart product in clinical studies with recent positive data after previous endpoint failure, indicative of statistical benefit. In 2014 they secured additional auto cell therapy products from Sanofi (Carticel & MACI – cartilage and Epicel – skin) which had previously received certain market authorizations and are generating revenue with patient benefit.

Indicative data sets for comparative analysis and ratio breakout are yet to be tabulated with regard to which conditions and methodologies the cells work well for and in which cases they don’t help all that much or at all. However, one must be cautious when assessing the efficacy value of cellular products as they are biologics and there are many issues relating to their degree of effectiveness, such as: their source; derivation method; inherent donor variability; passage potency; culture conditions & scale-up manufacturing; cold chain methodology; target indication; patient population; disease states and application methods, amongst others. As a result not all cellular products will perform well in human studies. These issues play a significant role in whether they achieve benefit in tests on patients, and to what extent in relation to standard of care. Although the jury is still out there is a general agreement based on empirical data that these cells are on the whole safe, when developed and used appropriately. Where they have been shown to have positive outcome and biological activity there is acknowledged room for improvement with regard to enhancing efficiency, potency and cell mechanistic action, which is encouraging.

One aspect of the development of industrial scale cellular therapies speaks to the need for increased replicative capacity, lower passaged products and standardization via use of optimization technologies and shifting to pluripotent cell sources instead of donor derived batch processing of multipotent cells.

Octane Bioreactors

As a result of this progressive development culture method adjustments gleaned from the early pioneering work of MSC development are giving rise to efficiencies of process and improved manufacturing protocols for next generation methods in both multipotent and pluripotent products. The above mentioned early leaders in MSC product offerings are beginning to line up their treatments for entry to the market, while the sector looks to prepare and trial the more advanced cell factories of the future.

UC Davis MSC Investigators

This momentum is also being driven by the rise of synthetic constructs using MSCs - the personalized tailoring of targeted medicines for improved performance. MSCs possess inherent homing and immunomodulatory properties and therefore are ideal for use in combination with gene and nano technologies. In addition, the extraction of the inherent cell properties of MSCs for standalone biologic products adds to the overall picture and excitement in the field.

MSC products are representative of the wider cell therapeutic field and are the standard bearers in the effort to bridge the shifting paradigms of new treatment modalities for patients in need.

Cheers

Ref: Sector Update on Asian Market for MSCs > "Cell Therapy in Asia Erupts with Partnerships and Joint Ventures"

Progress and the Circle of Scientific Medical Innovation

Designing an adaptable system without the known variables is often an exercise in caution, unless of course you have been down a similar road before and can rely on established templates for creating repurposed guidelines. In some cases however old parameters simply don't fit any longer and the opportunity to engage in the development of more flexible rules with the benefit of hindsight becomes a net positive in the never ending cycle of innovation driven progress.

A series of high profile developments along this path have taken place of late on the topic of genetics and the advent of gene editing technologies that have the potential to alter the fate of human disease and the burden it represents to society. These policy reviews and the resulting position statements have been brought on by concerns that human gene editing presents a challenge to the perceived boundaries by which scientific discovery and possible therapeutic interventions are applied. 

However, as we have seen knowledge trumps and is critical to all human endeavors, given information is paramount to decision making. Accumulating scientific data in the unknown cause and effect realm of biological systems provides the fundamental opportunity to address the task of solving real world problems. This is the tenant by which translational science has always operated and without which we wouldn't have made profound human advances to our condition.     

Existing legislation in Western countries has provided a basis for clarification on the scope of scientific and translational activities, as reviewed here. Europe expressly prohibits at present germ line editing for reproduction. The UK has always had a pro-knowledge framework for discovery using early stage fertilized pre-embryos up to 14 days. The US presently restricts Federal Funding on embryo creation for research and when destructive practices are employed in the lab. 

What is apparent now is the scientific community's consensus on the inherent value of lab study of early embryonic state development using genetic tools to advance knowledge through research while adhering to the principals of caution in progressing any attempts to implement the alteration of the germ line for reproductive purposes. This was the Middle Way path.

The US National Academies summation of their International Summit on Gene Editing affirmed the above in early December last year and called for an ongoing forum to further the dialogue on the topic as the science develops with a view to establishing new recommended guidelines if and when appropriate. The fluid nature of the science requires such and was therefore prudent to set this investigative precedent for all respective regulatory bodies to consider, including the US. 

Previously the UK reaffirmed its position as a leading member of the international scientific community by being the first country to consider Mitochondrial DNA replacement therapy for families with genetic disorders wishing to have a baby free of the diseases associated with such inherited problems. Most recently the UK has agreed to allow genetic research on fertilized pre-embryos for infertility studies without intent to implant for reproductive purposes and always adhering to the prior 14 day limit on embryo development. A modification to the UK law was required for the Mitochondrial DNA therapy to proceed to review stage, while the research on early pre-embryos was already allowable under existing legislative framework which required prior approval and strict oversight.

Following on from the UK's position on Mitochondrial DNA therapy the US National Academies earlier this week announced its recommendation on this genetic intervention procedure for germ-line modification application. The result being an additional affirmation of the scientific potential to alleviate disease through continued research and potential use of the technology in the US. Notable was the necessary recommended investigational support for early pre-embryo studies. Current congressional restrictions inhibit actual Federal support for such studies on viable early stage pre-embryos. This may change in the fiscal year 2017 appropriations Bill as the restriction is not permanent. Support for non-viable pre-embryo research was expressly noted in the US National Academies recommendation paper.           

Both the ISSCR and CIRM have previously stated that they support research on early stage pre-embryos for scientific purposes and have reiterated that position also this week while calling for renewed study of the societal implication of gene therapy and germ line editing.

Commercially the recent change in the position of the European Patent Office on the acceptable use of non-viable pre-embryos methods via germ-line modification brings the alignment closer together and bodes well for the application of various stalled avenues of translational science for the benefit of patients in need. 

Coming around full circle, there would be little progress without the support for all forms of scientific innovation.

Advocacy for Cures.

Cheers

Refs:

1. International Summit on Human Gene Editing Washington DC - "On Human Gene Editing: International Summit Statement" (Dec. 3rd 2016)
2. UK "Scientists get 'gene editing' go-ahead" (BBC Feb. 1st 2016)
3. The National Academies "Clinical Investigations of Mitochondrial Replacement Techniques Are ‘Ethically Permissible’ If Significant Conditions Are Met, Says New Report" (Feb. 3rd 2016)
4. California Stem Cell Report items by David Jensen re: CIRM (1,2) & ISSCR (3) (Feb. 5th 2016)
5. Related blog posts: 1, 2, 3, 4