Posted on by Dr. Francis Collins
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) . 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 . 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 .
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.
 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]
 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.
 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.
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
Posted on by Dr. Francis Collins
Developing faster, more convenient ways of testing for coronavirus disease 2019 (COVID-19) will be essential to our efforts to end this deadly pandemic. Despite the tremendous strides that have been made in diagnostics over the past seven months, we still need more innovation.
We need reliable, affordable tests for the presence SARS-CoV-2—the novel coronavirus that causes COVID-19—that do not take hours or days to deliver results. We need tests that are more user friendly, and that don’t rely on samples collected by swabs that have to be inserted deep into the nose by someone wearing PPE. We need tests that can be performed at the point-of-care, whether a doctor’s office, urgent care clinic, long-term care facility, or even a home. Ideally, such tests should also be able to integrate with mobile devices to convey results and transmit data seamlessly. Above all, we need tests that are accessible to everyone.
Most current diagnostic tests for SARS-CoV-2 involve detecting viral genetic material using a decades-old technology called the polymerase chain reaction (PCR). If there’s even a tiny bit of viral genetic material in a patient’s sample, PCR can amplify the material millions of times so that it can be readily detected. The problem is that this amplification process is time-consuming and requires a thermal cycling machine that’s generally operated by trained personnel in sophisticated lab settings.
To spur the creation of new approaches that can rapidly expand access to testing, NIH launched the Rapid Acceleration of Diagnostics (RADx) program in late April 2020. This fast-paced, innovative effort, conducted in partnership with the Office of the Assistant Secretary of Health, the Biomedical Advanced Research and Development Authority (BARDA), and the Department of Defense, is supported by $1.5 billion in federal stimulus funding. The goal? To expand diagnostic testing capacity for COVID-19 in the United States to about 6 million tests per day by December. That’s quite a leap forward because our nation’s current testing capacity is currently about 1 million tests per day.
Just yesterday, I joined other NIH leaders in authoring a special report in the New England Journal of Medicine that describes RADx’s main activities, and provides an update on the remarkable progress that’s been made in just three short months . In a nutshell, RADx consists of four components: RADx-tech, RADx Advanced Technology Platforms (RADx-ATP). RADx Radical (RADx-rad), and RADx Underserved Populations (RADx-UP).
Though all parts of RADx are operating on a fast-track, RADx-tech has embraced its rapid timelines in a can-do manner unlike anything that I’ve encountered in my 27 years in government. Here’s how the process, which has been likened to a scientific “shark tank,” works.
Once an applicant submits a test idea to RADx-tech, it’s reviewed within a day by a panel of 30 experts. If approved, the application moves to a highly competitive “shark-tank” in which a team of experts spend about 150 to 200 person-hours with the applicant evaluating the technical, clinical, and commercial strengths and weaknesses of the proposed test.
From there, a detailed proposal is presented to a steering committee, and then sent to NIH. If we at NIH think it’s a great idea, promising early-stage technologies enter what’s called “phase one” development, with considerable financial support and the expectation that the applicant will hit its validation milestones within a month. Technologies that succeed can then go to “phase two”, where support is provided for scale-up of tests for meeting regulatory requirements and supporting manufacture, scale-up, and distribution.
The major focus of RADx-tech is to simplify and speed diagnostic testing for COVID-19. Tests now under development include a variety of mobile devices that can be used at a doctor’s office or other point-of-care settings, and give results in less than an hour. In addition, about half of the tests now under development use saliva or another alternative to samples gathered via nasal swabs.
As Americans think about how to move back safely into schools, workspaces, and other public areas in the era of COVID-19, it is clear that we need to figure out ways to make it easier for everyone to get tested. To attain that goal, RADx has three other components that build on different aspects of this social imperative:
• RADx Advanced Technology Platforms (RADx-ATP). This program offers a rapid-response application process for firms with existing point-of-care technologies authorized by the Food and Drug Administration (FDA) for detecting SARS-CoV-2. These technologies are already advanced enough that they don’t need the shark tank. The RADx-ATP program provides support for scaling up production to between 20,000 and 100,000 tests per day by the fall. Another component of this program provides support for expanding automated “mega-labs” to increase testing capacity across the country by another 100,000 to 250,000 tests per day.
• RADx Radical (RADx-rad). The program seeks to fuel the development of truly futuristic testing technologies. For example, it supports projects that use biomarkers to detect an infection or predict the severity of disease, including the likelihood of developing COVID-related multisystem inflammatory syndrome in children (MIS-C). Other areas of interest include the use of biosensors to detect the presence of the virus in a person’s breath and the analysis of wastewater to conduct community-based surveillance.
• RADx Underserved Populations (RADx-UP). Data collected over the past several months make it clear that Blacks, Latinxs, and American Indians/Alaska Natives are hospitalized and die of COVID-19 at disproportionately higher rates than other groups. RADx-UP aims to engage underserved communities to improve access to testing. Such actions will include closely examining the factors that have led to the disproportionate burden of the pandemic on underserved populations, as well as building infrastructure that can be leveraged to provide optimal access and uptake of SARS-CoV-2 testing in such communities.
At NIH, we have great hopes for what RADx-supported research will do to help bring to an end the greatest public health crisis of our generation. Yet the benefits may not end there. The diagnostic testing technologies developed here will have many other applications moving forward. Long after the COVID-19 pandemic becomes a chapter in history books, I’m convinced the RADx model of rapid innovation will be inspiring future generations of researchers as they look for creative new ways to address other diseases and conditions.
 Rapid scaling up of COVID-19 diagnostic testing in the United States—The NIH RADx Initiative. Tromberg BJ, Schwetz TA, Perez-Stable E, Hodes RJ. Woychick RP, Bright RA, Fleurence RL, Collins FS. NEJM; 2020 July 16. [Online publication ahead of print]
Coronavirus (COVID-19) (NIH)
“NIH mobilizes national innovation initiative for COVID-19 diagnostics,” NIH news release, April 29, 2020.
Posted on by Dr. Francis Collins
When injury strikes a limb or an organ, our bodies usually heal quickly and correctly. But for some people, the healing process doesn’t shut down properly, leading to excess fibrous tissue, scarring, and potentially life-threatening organ damage.
This permanent scarring, known as fibrosis, can occur in almost every tissue of the body, including the heart and lungs. With support from a 2019 NIH Director’s New Innovator Award, April Kloxin is applying her expertise in materials science and bioengineering to build sophisticated fibrosis-in-a-dish models for unraveling this complex process in her lab at the University of Delaware, Newark.
Though Kloxin is interested in all forms of fibrosis, she’s focusing first on the incurable and often-fatal lung condition called idiopathic pulmonary fibrosis (IPF). This condition, characterized by largely unexplained thickening and stiffening of lung tissue, is diagnosed in about 50,000 people each year in the United States.
IPF remains poorly understood, in part because it often is diagnosed when the disease is already well advanced. Kloxin hopes to turn back the clock and start to understand the disease at an earlier stage, when interventions might be more successful. The key is to develop a model that better recapitulates the complexity and irreversibility of the disease process in people.
Building that better model starts with simulating the meshwork of collagen and other proteins in the extracellular matrix (ECM) that undergird every tissue and organ in the body. The ECM’s interactions with our cells are essential in wound healing and, when things go wrong, also in causing fibrosis.
Kloxin will build three-dimensional hydrogels, crosslinked sponge-like networks of polymers, peptides, and proteins, with structures that more accurately capture the biological complexities of human tissues, including the ECMs within fibrous collagen-rich microenvironments. Her synthetic matrices can be triggered with light to lock in place and stiffen. The matrices also will make it possible to culture the lung’s epithelium, or outermost layer of cells, and connective tissue that surrounds it, to study cellular responses as the model shifts from a healthy and flexible to a stiffened, disease-like state.
Kloxin and her team will also integrate into their model system lung cells that have been engineered to fluoresce or light up under a microscope when the wound-healing program activates. Such fluorescent reporters will allow her team to watch for the first time how different cells and their nearby microenvironment respond as the composition of the ECM changes and stiffens. With this system, she’ll also be able to search for small molecules with the ability to turn off excessive wound healing.
The hope is that what’s learned with her New Innovator Award will lead to fresh insights and ultimately new treatments for this mysterious, hard-to-treat condition. But the benefits could be even more wide-ranging. Kloxin thinks that her findings will have implications for the prevention and treatment of other fibrotic diseases as well.
Idiopathic Pulmonary Fibrosis (National Heart, Lung, and Blood Institute/NIH)
April Kloxin Group (University of Delaware, Newark)
Kloxin Project Information (NIH RePORTER)
NIH Director’s New Innovator Award (Common Fund)
NIH Support: Common Fund; National Heart, Lung, and Blood Institute