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Celebrating NIH Science, Blogs, and Blog Readers!

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Happy holidays to one and all! As you may have heard, this is my last holiday season as the Director of the National Institutes of Health (NIH)—a post that I’ve held for the past 12 years and four months under three U.S. Presidents. And, wow, it really does seem like only yesterday that I started this blog!

At the blog’s outset, I said my goal was to “highlight new discoveries in biology and medicine that I think are game changers, noteworthy, or just plain cool.” More than 1,100 posts, 10 million unique visitors, and 13.7 million views later, I hope you’ll agree that goal has been achieved. I’ve also found blogging to be a whole lot of fun, as well as a great way to expand my own horizons and share a little of what I’ve learned about biomedical advances with people all across the nation and around the world.

So, as I sign off as NIH Director and return to my lab at NIH’s National Human Genome Research Institute (NHGRI), I want to thank everyone who’s ever visited this Blog—from high school students to people with health concerns, from biomedical researchers to policymakers. I hope that the evidence-based information that I’ve provided has helped and informed my readers in some small way.

In this my final post, I’m sharing a short video (see above) that highlights just a few of the blog’s many spectacular images, many of them produced by NIH-funded scientists during the course of their research. In the video, you’ll see a somewhat quirky collection of entries, but hopefully you will sense my enthusiasm for the potential of biomedical research to fight human disease and improve human health—from innovative immunotherapies for treating cancer to the gift of mRNA vaccines to combat a pandemic.

Over the years, I’ve blogged about many of the bold, new frontiers of biomedicine that are now being explored by research teams supported by NIH. Who would have imagined that, within the span of a dozen years, precision medicine would go from being an interesting idea to a driving force behind the largest-ever NIH cohort seeking to individualize the prevention and treatment of common disease? Or that today we’d be deep into investigations of precisely how the human brain works, as well as how human health may benefit from some of the trillions of microbes that call our bodies home?

My posts also delved into some of the amazing technological advances that are enabling breakthroughs across a wide range of scientific fields. These innovative technologies include powerful new ways of mapping the atomic structures of proteins, editing genetic material, and designing improved gene therapies.

So, what’s next for NIH? Let me assure you that NIH is in very steady hands as it heads into a bright horizon brimming with exceptional opportunities for biomedical research. Like you, I look forward to discoveries that will lead us even closer to the life-saving answers that we all want and need.

While we wait for the President to identify a new NIH director, Lawrence Tabak, who has been NIH’s Principal Deputy Director and my right arm for the last decade, will serve as Acting NIH Director. So, keep an eye out for his first post in early January!

As for me, I’ll probably take a little time to catch up on some much-needed sleep, do some reading and writing, and hopefully get out for a few more rides on my Harley with my wife Diane. But there’s plenty of work to do in my lab, where the focus is on type 2 diabetes and a rare disease of premature aging called Hutchinson-Gilford Progeria Syndrome. I’m excited to pursue those research opportunities and see where they lead.

In closing, I’d like to extend my sincere thanks to each of you for your interest in hearing from the NIH Director—and supporting NIH research—over the past 12 years. It’s been an incredible honor to serve you at the helm of this great agency that’s often called the National Institutes of Hope. And now, for one last time, Diane and I take great pleasure in sending you and your loved ones our most heartfelt wishes for Happy Holidays and a Healthy New Year!


Teaching the Immune System to Attack Cancer with Greater Precision

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Needle in a vial. Cancer cell in the background
Credit: PhotobyTawat/Shutterstock/Tom Deerink, National Institute of General Medical Sciences, NIH

To protect humans from COVID-19, the Pfizer and Moderna mRNA vaccines program human cells to translate the injected synthetic messenger RNA into the coronavirus spike protein, which then primes the immune system to arm itself against future appearances of that protein. It turns out that the immune system can also be trained to spot and attack distinctive proteins on cancer cells, killing them and leaving healthy cells potentially untouched.

While these precision cancer vaccines remain experimental, researchers continue to make basic discoveries that move the field forward. That includes a recent NIH-funded study in mice that helps to refine the selection of protein targets on tumors as a way to boost the immune response [1]. To enable this boost, the researchers first had to discover a possible solution to a longstanding challenge in developing precision cancer vaccines: T cell exhaustion.

The term refers to the immune system’s complement of T cells and their capacity to learn to recognize foreign proteins, also known as neoantigens, and attack them on cancer cells to shrink tumors. But these responding T cells can exhaust themselves attacking tumors, limiting the immune response and making its benefits short-lived.

In this latest study, published in the journal Cell, Tyler Jacks and Megan Burger, Massachusetts Institute of Technology, Cambridge, help to explain this phenomenon of T cell exhaustion. The researchers found in mice with lung tumors that the immune system initially responds as it should. It produces lots of T cells that target many different cancer-specific proteins.

Yet there’s a problem: various subsets of T cells get in each other’s way. They compete until, eventually, one of those subsets becomes the dominant T cell type. Even when those dominant T cells grow exhausted, they still remain in the tumor and keep out other T cells, which might otherwise attack different neoantigens in the cancer.

Building on this basic discovery, the researchers came up with a strategy for developing cancer vaccines that can “awaken” T cells and reinvigorate the body’s natural cancer-fighting abilities. The strategy might seem counterintuitive. The researchers vaccinated mice with neoantigens that provide a weak but encouraging signal to the immune cells responsible for presenting the distinctive cancer protein target, or antigen, to T cells. It’s those T cells that tend to get suppressed in competition with other T cells.

When the researchers vaccinated the mice with one of those neoantigens, the otherwise suppressed T cells grew in numbers and better targeted the tumor. What’s more, the tumors shrank by more than 25 percent on average.

Research on this new strategy remains in its early stages. The researchers hope to learn if this approach to cancer vaccines might work even better when used in combination with immunotherapy drugs, which unleash the immune system against cancer in other ways.

It’s also possible that the recent and revolutionary success of mRNA vaccines for preventing COVID-19 actually could help. An important advantage of mRNA is that it’s easy for researchers to synthesize once they know the specific nucleic acid sequence of a protein target, and they can even combine different mRNA sequences to make a multiplex vaccine that primes the immune system to recognize multiple neoantigens. Now that we’ve seen how well mRNA vaccines work to prompt a desired immune response against COVID-19, this same technology can be used to speed the development and testing of future vaccines, including those designed precisely to fight cancer.

Reference:

[1] Antigen dominance hierarchies shape TCF1+ progenitor CD8 T cell phenotypes in tumors. Burger ML, Cruz AM, Crossland GE, Gaglia G, Ritch CC, Blatt SE, Bhutkar A, Canner D, Kienka T, Tavana SZ, Barandiaran AL, Garmilla A, Schenkel JM, Hillman M, de Los Rios Kobara I, Li A, Jaeger AM, Hwang WL, Westcott PMK, Manos MP, Holovatska MM, Hodi FS, Regev A, Santagata S, Jacks T. Cell. 2021 Sep 16;184(19):4996-5014.e26.

Links:

Cancer Treatment Vaccines (National Cancer Institute/NIH)

The Jacks Lab (Massachusetts Institute of Technology, Cambridge)

NIH Support: National Cancer Institute; National Heart, Lung, and Blood Institute


An Evolutionary Guide to New Immunotherapies

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Credit: Dave Titensor, University of Utah, Salt Lake City

One of the best ways to learn how something works is to understand how it’s built. How it came to be. That’s true not only if you play a guitar or repair motorcycle engines, but also if you study the biological systems that make life possible. Evolutionary studies, comparing the development of these systems across animals and organisms, are now leading to many unexpected biological discoveries and promising possibilities for preventing and treating human disease.

While there are many evolutionary questions to ask, Brenda Bass, a distinguished biochemist at University of Utah, Salt Lake City, has set her sights on a particularly profound one: How has innate immunity evolved through the millennia in all living things, including humans? Innate immunity is the immune system’s frontline defense, the first responders that take control of an emerging infectious situation and, if needed, signal for backup.

Exploring the millennia for clues about innate immunity takes a special team, and Bass has assembled a talented one. It includes her Utah colleague Nels Elde, a geneticist; immunologist Dan Stetson, University of Washington, Seattle; and biochemist Jane Jackman, Ohio State University, Columbus.

With a 2020 NIH Director’s Transformative Research Award, this hard-working team will embark on studies looking back at 450 million years of evolution: the point in time when animals diverged to develop very distinct methods of innate immune defense [1]. The team members hope to uncover new possibilities encoded in the innate immune system, especially those that might be latent but still workable. The researchers will then explore whether their finds can be repurposed not only to boost our body’s natural response to external threats but also to internal threats like cancer.

Bass brings a unique perspective to the project. As a postdoc in the 1980s, she stumbled upon a whole new class of enzymes, called ADARs, that edit RNA [2]. Their function was mysterious at the time. It turns out that ADARs specifically edit a molecule called double-stranded RNA (dsRNA). When viruses infect cells in animals, including humans, they make dsRNA, which the innate immune system detects as a sign that a cell has been invaded.

It also turns out that animal cells make their own dsRNA. Over the years, Bass and her lab have identified thousands of dsRNAs made in animal cells—in fact, a significant number of human genes produce dsRNA [3]. Also interesting, ADARs are crucial to marking our own dsRNA as “self” to avoid triggering an immune response when we don’t need it [4].

Bass and others have found that evolution has produced dramatic differences in the biochemical pathways powering the innate immune system. In vertebrate animals, dsRNA leads to release of the immune chemical interferon, a signaling pathway that invertebrate species don’t have. Instead, in response to detecting dsRNA from an invader, and repelling it, worms and other invertebrates trigger a gene-silencing pathway known as RNA interference, or RNAi.

With the new funding, Bass and team plan to mix and match immune strategies from simple and advanced species, across evolutionary time, to craft an entirely new set of immune tools to fight disease. The team will also build new types of targeted immunotherapies based on the principles of innate immunity. Current immunotherapies, which harness a person’s own immune system to fight disease, target infections, autoimmune disorders, and cancer. But they work through our second-line adaptive immune response, which is a biological system unique to vertebrates.

Bass and her team will first hunt for more molecules like ADARs: innate immune checkpoints, as they refer to them. The name comes from a functional resemblance to the better-known adaptive immune checkpoints PD-1 and CTLA-4, which sparked a revolution in cancer immunotherapy. The team will run several screens that sort molecules successful at activating innate immune responses—both in invertebrates and in mammals—hoping to identify a range of durable new immune switches that evolution skipped over but that might be repurposed today.

Another intriguing direction for this research stems from the observation that decreasing normal levels of ADARs in tumors kickstarts innate immune responses that kill cancer cells [5]. Along these lines, the scientists plan to test newly identified immune switches to look for novel ways to fight cancer where existing approaches have not worked.

Evolution is the founding principle for all of biology—organisms learn from what works to improve their ability to survive. In this case, research to re-examine such lessons and apply them for new uses may help transform bygone evolution into a therapeutic revolution!

References:

[1] Evolution of adaptive immunity from transposable elements combined with innate immune systems. Koonin EV, Krupovic M. Nat Rev Genet. 2015 Mar;16(3):184-192.

[2] A developmentally regulated activity that unwinds RNA duplexes. Bass BL, Weintraub H. Cell. 1987 Feb 27;48(4):607-613.

[3] Mapping the dsRNA World. Reich DP, Bass BL. Cold Spring Harb Perspect Biol. 2019 Mar 1;11(3):a035352.

[4] To protect and modify double-stranded RNA – the critical roles of ADARs in development, immunity and oncogenesis. Erdmann EA, Mahapatra A, Mukherjee P, Yang B, Hundley HA. Crit Rev Biochem Mol Biol. 2021 Feb;56(1):54-87.

[5] Loss of ADAR1 in tumours overcomes resistance to immune checkpoint blockade. Ishizuka JJ, Manguso RT, Cheruiyot CK, Bi K, Panda A, et al. Nature. 2019 Jan;565(7737):43-48.

Links:

Bass Lab (University of Utah, Salt Lake City)

Elde Lab (University of Utah)

Jackman Lab (Ohio State University, Columbus)

Stetson Lab (University of Washington, Seattle)

Bass/Elde/Jackman/Stetson Project Information (NIH RePORTER)

NIH Director’s Transformative Research Award Program (Common Fund)

NIH Support: Common Fund; National Cancer Institute


The People’s Picks for Best Posts

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It’s 2021—Happy New Year! Time sure flies in the blogosphere. It seems like just yesterday that I started the NIH Director’s Blog to highlight recent advances in biology and medicine, many supported by NIH. Yet it turns out that more than eight years have passed since this blog got rolling and we are fast approaching my 1,000th post!

I’m pleased that millions of you have clicked on these posts to check out some very cool science and learn more about NIH and its mission. Thanks to the wonders of social media software, we’ve been able to tally up those views to determine each year’s most-popular post. So, I thought it would be fun to ring in the New Year by looking back at a few of your favorites, sort of a geeky version of a top 10 countdown or the People’s Choice Awards. It was interesting to see what topics generated the greatest interest. Spoiler alert: diet and exercise seemed to matter a lot! So, without further ado, I present the winners:

2013: Fighting Obesity: New Hopes from Brown Fat. Brown fat, one of several types of fat made by our bodies, was long thought to produce body heat rather than store energy. But Shingo Kajimura and his team at the University of California, San Francisco, showed in a study published in the journal Nature, that brown fat does more than that. They discovered a gene that acts as a molecular switch to produce brown fat, then linked mutations in this gene to obesity in humans.

What was also nice about this blog post is that it appeared just after Kajimura had started his own lab. In fact, this was one of the lab’s first publications. One of my goals when starting the blog was to feature young researchers, and this work certainly deserved the attention it got from blog readers. Since highlighting this work, research on brown fat has continued to progress, with new evidence in humans suggesting that brown fat is an effective target to improve glucose homeostasis.

2014: In Memory of Sam Berns. I wrote this blog post as a tribute to someone who will always be very near and dear to me. Sam Berns was born with Hutchinson-Gilford progeria syndrome, one of the rarest of rare diseases. After receiving the sad news that this brave young man had passed away, I wrote: “Sam may have only lived 17 years, but in his short life he taught the rest of us a lot about how to live.”

Affecting approximately 400 people worldwide, progeria causes premature aging. Without treatment, children with progeria, who have completely normal intellectual development, die of atherosclerotic cardiovascular disease, on average in their early teens.

From interactions with Sam and his parents in the early 2000s, I started to study progeria in my NIH lab, eventually identifying the gene responsible for the disorder. My group and others have learned a lot since then. So, it was heartening last November when the Food and Drug Administration approved the first treatment for progeria. It’s an oral medication called Zokinvy (lonafarnib) that helps prevent the buildup of defective protein that has deadly consequences. In clinical trials, the drug increased the average survival time of those with progeria by more than two years. It’s a good beginning, but we have much more work to do in the memory of Sam and to help others with progeria. Watch for more about new developments in applying gene editing to progeria in the next few days.

2015: Cytotoxic T Cells on Patrol. Readers absolutely loved this post. When the American Society of Cell Biology held its first annual video competition, called CellDance, my blog featured some of the winners. Among them was this captivating video from Alex Ritter, then working with cell biologist Jennifer Lippincott-Schwartz of NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development. The video stars a roving, specialized component of our immune system called cytotoxic T cells. Their job is to seek out and destroy any foreign or detrimental cells. Here, these T cells literally convince a problem cell to commit suicide, a process that takes about 10 minutes from detection to death.

These cytotoxic T cells are critical players in cancer immunotherapy, in which a patient’s own immune system is enlisted to control and, in some cases, even cure the cancer. Cancer immunotherapy remains a promising area of research that continues to progress, with a lot of attention now being focused on developing immunotherapies for common, solid tumors like breast cancer. Ritter is currently completing a postdoctoral fellowship in the laboratory of Ira Mellman, Genentech, South San Francisco. His focus has shifted to how cancer cells protect themselves from T cells. And video buffs—get this—Ritter says he’s now created even cooler videos that than the one in this post.

2016: Exercise Releases Brain-Healthy Protein. The research literature is pretty clear: exercise is good for the brain. In this very popular post, researchers led by Hyo Youl Moon and Henriette van Praag of NIH’s National Institute on Aging identified a protein secreted by skeletal muscle cells to help explore the muscle-brain connection. In a study in Cell Metabolism, Moon and his team showed that this protein called cathepsin B makes its way into the brain and after a good workout influences the development of new neural connections. This post is also memorable to me for the photo collage that accompanied the original post. Why? If you look closely at the bottom right, you’ll see me exercising—part of my regular morning routine!

2017: Muscle Enzyme Explains Weight Gain in Middle Age. The struggle to maintain a healthy weight is a lifelong challenge for many of us. While several risk factors for weight gain, such as counting calories, are within our control, there’s a major one that isn’t: age. Jay Chung, a researcher with NIH’s National Heart, Lung, and Blood Institute, and his team discovered that the normal aging process causes levels of an enzyme called DNA-PK to rise in animals as they approach middle age. While the enzyme is known for its role in DNA repair, their studies showed it also slows down metabolism, making it more difficult to burn fat.

Since publishing this paper in Cell Metabolism, Chung has been busy trying to understand how aging increases the activity of DNA-PK and its ability to suppress renewal of the cell’s energy-producing mitochondria. Without renewal of damaged mitochondria, excess oxidants accumulate in cells that then activate DNA-PK, which contributed to the damage in the first place. Chung calls it a “vicious cycle” of aging and one that we’ll be learning more about in the future.

2018: Has an Alternative to Table Sugar Contributed to the C. Diff. Epidemic? This impressive bit of microbial detective work had blog readers clicking and commenting for several weeks. So, it’s no surprise that it was the runaway People’s Choice of 2018.

Clostridium difficile (C. diff) is a common bacterium that lives harmlessly in the gut of most people. But taking antibiotics can upset the normal balance of healthy gut microbes, allowing C. diff. to multiply and produce toxins that cause inflammation and diarrhea.

In the 2000s, C. diff. infections became far more serious and common in American hospitals, and Robert Britton, a researcher at Baylor College of Medicine, Houston, wanted to know why. He and his team discovered that two subtypes of C. diff have adapted to feed on the sugar trehalose, which was approved as a food additive in the United States during the early 2000s. The team’s findings, published in the journal Nature, suggested that hospitals and nursing homes battling C. diff. outbreaks may want to take a closer look at the effect of trehalose in the diet of their patients.

2019: Study Finds No Benefit for Dietary Supplements. This post that was another one that sparked a firestorm of comments from readers. A team of NIH-supported researchers, led by Fang Fang Zhang, Tufts University, Boston, found that people who reported taking dietary supplements had about the same risk of dying as those who got their nutrients through food. What’s more, the mortality benefits associated with adequate intake of vitamin A, vitamin K, magnesium, zinc, and copper were limited to amounts that are available from food consumption. The researchers based their conclusion on an analysis of the well-known National Health and Nutrition Examination Survey (NHANES) between 1999-2000 and 2009-2010 survey data. The team, which reported its data in the Annals of Internal Medicine, also uncovered some evidence suggesting that certain supplements might even be harmful to health when taken in excess.

2020: Genes, Blood Type Tied to Risk of Severe COVID-19. Typically, my blog focuses on research involving many different diseases. That changed in 2020 due to the emergence of a formidable public health challenge: the coronavirus disease 2019 (COVID-19) pandemic. Since last March, the blog has featured 85 posts on COVID-19, covering all aspects of the research response and attracting more visitors than ever. And which post got the most views? It was one that highlighted a study, published last June in the New England Journal of Medicine, that suggested the clues to people’s variable responses to COVID-19 may be found in our genes and our blood types.

The researchers found that gene variants in two regions of the human genome are associated with severe COVID-19 and correspondingly carry a greater risk of COVID-19-related death. The two stretches of DNA implicated as harboring risks for severe COVID-19 are known to carry some intriguing genes, including one that determines blood type and others that play various roles in the immune system.

In fact, the findings suggest that people with blood type A face a 50 percent greater risk of needing oxygen support or a ventilator should they become infected with the novel coronavirus. In contrast, people with blood type O appear to have about a 50 percent reduced risk of severe COVID-19.

That’s it for the blog’s year-by-year Top Hits. But wait! I’d also like to give shout outs to the People’s Choice winners in two other important categories—history and cool science images.

Top History Post: HeLa Cells: A New Chapter in An Enduring Story. Published in August 2013, this post remains one of the blog’s greatest hits with readers. The post highlights science’s use of cancer cells taken in the 1950s from a young Black woman named Henrietta Lacks. These “HeLa” cells had an amazing property not seen before: they could be grown continuously in laboratory conditions. The “new chapter” featured in this post is an agreement with the Lacks family that gives researchers access to the HeLa genome data, while still protecting the family’s privacy and recognizing their enormous contribution to medical research. And the acknowledgments rightfully keep coming from those who know this remarkable story, which has been chronicled in both book and film. Recently, the U.S. Senate and House of Representatives passed the Henrietta Lacks Enhancing Cancer Research Act to honor her extraordinary life and examine access to government-funded cancer clinical trials for traditionally underrepresented groups.

Top Snapshots of Life: A Close-up of COVID-19 in Lung Cells. My blog posts come in several categories. One that you may have noticed is “Snapshots of Life,” which provides a showcase for cool images that appear in scientific journals and often dominate Science as Art contests. My blog has published dozens of these eye-catching images, representing a broad spectrum of the biomedical sciences. But the blog People’s Choice goes to a very recent addition that reveals exactly what happens to cells in the human airway when they are infected with the coronavirus responsible for COVID-19. This vivid image, published in the New England Journal of Medicine, comes from the lab of pediatric pulmonologist Camille Ehre, University of North Carolina at Chapel Hill. This image squeezed in just ahead of another highly popular post from Steve Ramirez, Boston University, in 2019 that showed “What a Memory Looks Like.”

As we look ahead to 2021, I want to thank each of my blog’s readers for your views and comments over the last eight years. I love to hear from you, so keep on clicking! I’m confident that 2021 will generate a lot more amazing and bloggable science, including even more progress toward ending the COVID-19 pandemic that made our past year so very challenging.


Insulin-Producing Organoids Offer Hope for Treating Type 1 Diabetes

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Insulin-producing organoid
Caption: Human islet-like organoids express insulin (green). Credit: Salk Institute

For the 1 to 3 million Americans with type 1 diabetes, the immune system destroys insulin-producing beta cells of the pancreas that control the amount of glucose in the bloodstream. As a result, these individuals must monitor their blood glucose often and take replacement doses of insulin to keep it under control. Such constant attention, combined with a strict diet to control sugar intake, is challenging—especially for children.

For some people with type 1 diabetes, there is another option. They can be treated—maybe even cured—with a pancreatic islet cell transplant from an organ donor. These transplanted islet cells, which harbor the needed beta cells, can increase insulin production. But there’s a big catch: there aren’t nearly enough organs to go around, and people who receive a transplant must take lifelong medications to keep their immune system from rejecting the donated organ.

Now, NIH-funded scientists, led by Ronald Evans of the Salk Institute, La Jolla, CA, have devised a possible workaround: human islet-like organoids (HILOs) [1]. These tiny replicas of pancreatic tissue are created in the laboratory, and you can see them above secreting insulin (green) in a lab dish. Remarkably, some of these HILOs have been outfitted with a Harry Potter-esque invisibility cloak to enable them to evade immune attack when transplanted into mice.

Over several years, Doug Melton’s lab at Harvard University, Cambridge, MA, has worked steadily to coax induced pluripotent stem (iPS) cells, which are made from adult skin or blood cells, to form miniature islet-like cells in a lab dish [2]. My own lab at NIH has also been seeing steady progress in this effort, working with collaborators at the New York Stem Cell Foundation.

Although several years ago researchers could get beta cells to make insulin, they wouldn’t secrete the hormone efficiently when transplanted into a living mouse. About four years ago, the Evans lab found a possible solution by uncovering a genetic switch called ERR-gamma that when flipped, powered up the engineered beta cells to respond continuously to glucose and release insulin [3].

In the latest study, Evans and his team developed a method to program HILOs in the lab to resemble actual islets. They did it by growing the insulin-producing cells alongside each other in a gelatinous, three-dimensional chamber. There, the cells combined to form organoid structures resembling the shape and contour of the islet cells seen in an actual 3D human pancreas. After they are switched on with a special recipe of growth factors and hormones, these activated HILOs secrete insulin when exposed to glucose. When transplanted into a living mouse, this process appears to operate just like human beta cells work inside a human pancreas.

Another major advance was the invisibility cloak. The Salk team borrowed the idea from cancer immunotherapy and a type of drug called a checkpoint inhibitor. These drugs harness the body’s own immune T cells to attack cancer. They start with the recognition that T cells display a protein on their surface called PD-1. When T cells interact with other cells in the body, PD-1 binds to a protein on the surface of those cells called PD-L1. This protein tells the T cells not to attack. Checkpoint inhibitors work by blocking the interaction of PD-1 and PD-L1, freeing up immune cells to fight cancer.

Reversing this logic for the pancreas, the Salk team engineered HILOs to express PD-L1 on their surface as a sign to the immune system not to attack. The researchers then transplanted these HILOs into diabetic mice that received no immunosuppressive drugs, as would normally be the case to prevent rejection of these human cells. Not only did the transplanted HILOs produce insulin in response to glucose spikes, they spurred no immune response.

So far, HILOs transplants have been used to treat diabetes for more than 50 days in diabetic mice. More research will be needed to see whether the organoids can function for even longer periods of time.

Still, this is exciting news, and provides an excellent example of how advances in one area of science can provide new possibilities for others. In this case, these insights provide fresh hope for a day when children and adults with type 1 diabetes can live long, healthy lives without the need for frequent insulin injections.

References:

[1] Immune-evasive human islet-like organoids ameliorate diabetes. [published online ahead of print, 2020 Aug 19]. Yoshihara E, O’Connor C, Gasser E, Wei Z, Oh TG, Tseng TW, Wang D, Cayabyab F, Dai Y, Yu RT, Liddle C, Atkins AR, Downes M, Evans RM. Nature. 2020 Aug 19. [Epub ahead of publication]

[2] Generation of Functional Human Pancreatic β Cells In Vitro. Pagliuca FW, Millman JR, Gürtler M, Segel M, Van Dervort A, Ryu JH, Peterson QP, Greiner D, Melton DA. Cell. 2014 Oct 9;159(2):428-39.

[3] ERRγ is required for the metabolic maturation of therapeutically functional glucose-responsive β cells. Yoshihara E, Wei Z, Lin CS, Fang S, Ahmadian M, Kida Y, Tseng T, Dai Y, Yu RT, Liddle C, Atkins AR, Downes M, Evans RM. Cell Metab. 2016 Apr 12; 23(4):622-634.

Links:

Type 1 Diabetes (National Institute of Diabetes and Digestive and Kidney Diseases/NIH)

Pancreatic Islet Transplantation (National Institute of Diabetes and Digestive and Kidney Diseases)

The Nobel Prize in Physiology or Medicine 2012” for Induced Pluripotent Stem Cells, The Nobel Prize news release, October 8, 2012.

Evans Lab (Salk Institute, La Jolla, CA)

NIH Support: National Institute of Diabetes and Digestive and Kidney Diseases; National Cancer Institute


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