Skip to main content

Africa

Celebrating 2019 Biomedical Breakthroughs

Posted on by

Science 2019 Biomedical Breakthroughs and a Breakdown

Happy New Year! As we say goodbye to the Teens, let’s take a look back at 2019 and some of the groundbreaking scientific discoveries that closed out this remarkable decade.

Each December, the reporters and editors at the journal Science select their breakthrough of the year, and the choice for 2019 is nothing less than spectacular: An international network of radio astronomers published the first image of a black hole, the long-theorized cosmic singularity where gravity is so strong that even light cannot escape [1]. This one resides in a galaxy 53 million light-years from Earth! (A light-year equals about 6 trillion miles.)

Though the competition was certainly stiff in 2019, the biomedical sciences were well represented among Science’s “runner-up” breakthroughs. They include three breakthroughs that have received NIH support. Let’s take a look at them:

In a first, drug treats most cases of cystic fibrosis: Last October, two international research teams reported the results from phase 3 clinical trials of the triple drug therapy Trikafta to treat cystic fibrosis (CF). Their data showed Trikafta effectively compensates for the effects of a mutation carried by about 90 percent of people born with CF. Upon reviewing these impressive data, the Food and Drug Administration (FDA) approved Trikafta, developed by Vertex Pharmaceuticals.

The approval of Trikafta was a wonderful day for me personally, having co-led the team that isolated the CF gene 30 years ago. A few years later, I wrote a song called “Dare to Dream” imagining that wonderful day when “the story of CF is history.” Though we’ve still got more work to do, we’re getting a lot closer to making that dream come true. Indeed, with the approval of Trikafta, most people with CF have for the first time ever a real chance at managing this genetic disease as a chronic condition over the course of their lives. That’s a tremendous accomplishment considering that few with CF lived beyond their teens as recently as the 1980s.

Such progress has been made possible by decades of work involving a vast number of researchers, many funded by NIH, as well as by more than two decades of visionary and collaborative efforts between the Cystic Fibrosis Foundation and Aurora Biosciences (now, Vertex) that built upon that fundamental knowledge of the responsible gene and its protein product. Not only did this innovative approach serve to accelerate the development of therapies for CF, it established a model that may inform efforts to develop therapies for other rare genetic diseases.

Hope for Ebola patients, at last: It was just six years ago that news of a major Ebola outbreak in West Africa sounded a global health emergency of the highest order. Ebola virus disease was then recognized as an untreatable, rapidly fatal illness for the majority of those who contracted it. Though international control efforts ultimately contained the spread of the virus in West Africa within about two years, over 28,600 cases had been confirmed leading to more than 11,000 deaths—marking the largest known Ebola outbreak in human history. Most recently, another major outbreak continues to wreak havoc in northeastern Democratic Republic of Congo (DRC), where violent civil unrest is greatly challenging public health control efforts.

As troubling as this news remains, 2019 brought a needed breakthrough for the millions of people living in areas susceptible to Ebola outbreaks. A randomized clinical trial in the DRC evaluated four different drugs for treating acutely infected individuals, including an antibody against the virus called mAb114, and a cocktail of anti-Ebola antibodies referred to as REGN-EB3. The trial’s preliminary data showed that about 70 percent of the patients who received either mAb114 or the REGN-EB3 antibody cocktail survived, compared with about half of those given either of the other two medicines.

So compelling were these preliminary results that the trial, co-sponsored by NIH’s National Institute of Allergy and Infectious Diseases (NIAID) and the DRC’s National Institute for Biomedical Research, was halted last August. The results were also promptly made public to help save lives and stem the latest outbreak. All Ebola patients in the DRC treatment centers now are treated with one or the other of these two options. The trial results were recently published.

The NIH-developed mAb114 antibody and the REGN-EB3 cocktail are the first therapeutics to be shown in a scientifically rigorous study to be effective at treating Ebola. This work also demonstrates that ethically sound clinical research can be conducted under difficult conditions in the midst of a disease outbreak. In fact, the halted study was named Pamoja Tulinde Maisha (PALM), which means “together save lives” in Kiswahili.

To top off the life-saving progress in 2019, the FDA just approved the first vaccine for Ebola. Called Ervebo (earlier rVSV-ZEBOV), this single-dose injectable vaccine is a non-infectious version of an animal virus that has been genetically engineered to carry a segment of a gene from the Zaire species of the Ebola virus—the virus responsible for the current DRC outbreak and the West Africa outbreak. Because the vaccine does not contain the whole Zaire virus, it can’t cause Ebola. Results from a large study in Guinea conducted by the WHO indicated that the vaccine offered substantial protection against Ebola virus disease. Ervebo, produced by Merck, has already been given to over 259,000 individuals as part of the response to the DRC outbreak. The NIH has supported numerous clinical trials of the vaccine, including an ongoing study in West Africa.

Microbes combat malnourishment: Researchers discovered a few years ago that abnormal microbial communities, or microbiomes, in the intestine appear to contribute to childhood malnutrition. An NIH-supported research team followed up on this lead with a study of kids in Bangladesh, and it published last July its groundbreaking finding: that foods formulated to repair the “gut microbiome” helped malnourished kids rebuild their health. The researchers were able to identify a network of 15 bacterial species that consistently interact in the gut microbiomes of Bangladeshi children. In this month-long study, this bacterial network helped the researchers characterize a child’s microbiome and/or its relative state of repair.

But a month isn’t long enough to determine how the new foods would help children grow and recover. The researchers are conducting a similar study that is much longer and larger. Globally, malnutrition affects an estimated 238 million children under the age 5, stunting their normal growth, compromising their health, and limiting their mental development. The hope is that these new foods and others adapted for use around the world soon will help many more kids grow up to be healthy adults.

Measles Resurgent: The staff at Science also listed their less-encouraging 2019 Breakdowns of the Year, and unfortunately the biomedical sciences made the cut with the return of measles in the U.S. Prior to 1963, when the measles vaccine was developed, 3 to 4 million Americans were sickened by measles each year. Each year about 500 children would die from measles, and many more would suffer lifelong complications. As more people were vaccinated, the incidence of measles plummeted. By the year 2000, the disease was even declared eliminated from the U.S.

But, as more parents have chosen not to vaccinate their children, driven by the now debunked claim that vaccines are connected to autism, measles has made a very preventable comeback. Last October, the Centers for Disease Control and Prevention (CDC) reported an estimated 1,250 measles cases in the United States at that point in 2019, surpassing the total number of cases reported annually in each of the past 25 years.

The good news is those numbers can be reduced if more people get the vaccine, which has been shown repeatedly in many large and rigorous studies to be safe and effective. The CDC recommends that children should receive their first dose by 12 to 15 months of age and a second dose between the ages of 4 and 6. Older people who’ve been vaccinated or have had the measles previously should consider being re-vaccinated, especially if they live in places with low vaccination rates or will be traveling to countries where measles are endemic.

Despite this public health breakdown, 2019 closed out a memorable decade of scientific discovery. The Twenties will build on discoveries made during the Teens and bring us even closer to an era of precision medicine to improve the lives of millions of Americans. So, onward to 2020—and happy New Year!

Reference:

[1] 2019 Breakthrough of the Year. Science, December 19, 2019.

NIH Support: These breakthroughs represent the culmination of years of research involving many investigators and the support of multiple NIH institutes.


2019 Grand Challenges Annual Meeting

Posted on by

Global Challenges
Greetings from Africa. I am participating in the 2019 Grand Challenges Annual Meeting at the United Nations Conference Centre, Addis Ababa, Ethiopia. The Grand Challenges is a family of global initiatives supported by various funders around the world to address critical problems of health and development. Here, I took part in a panel discussion on October 28 during the meeting’s opening plenary session. The panel included (from left to right) Haitham El-noush, senior adviser, Innovation in Health and Development, Norwegian Agency for Development Cooperation, Oslo; Matshidiso Moeti, director, World Health Organization’s Regional Office for Africa, Brazzaville, Congo; Felix Dakora, president, African Academy of Sciences (AAS), Nairobi, Kenya; Francis Collins; Jennifer Blanke, vice president, Agriculture, Human and Social Development, African Development Bank Group, Abidjan, Ivory Coast; and Tom Kariuki, AAS’s director of programs. Among the topics raised during this stimulating conversation were the need for cooperation among the world’s scientific and political leaders and current efforts to prioritize African initiatives that will most immediately benefit human health. Credit: AAS

Study in Africa Yields New Diabetes Gene

Posted on by

Francis Collins Volunteering in Nigeria
Caption: Volunteering my medical services in Nigeria three decades ago inspired me to learn more about type 2 diabetes in Africa and beyond. Credit: Margaret Collins

When I volunteered to serve as a physician at a hospital in rural Nigeria more than 25 years ago, I expected to treat a lot of folks with infectious diseases, such as malaria and tuberculosis. And that certainly happened. What I didn’t expect was how many people needed care for type 2 diabetes (T2D) and the health problems it causes. Surprisingly, these individuals were generally not overweight, and the course of their illness seemed different than in the West.

The experience inspired me to join with other colleagues at Howard University, Washington, DC, to help found the Africa America Diabetes Mellitus (AADM) study. It aims to uncover genomic risk factors for T2D in Africa and, using that information, improve understanding of the condition around the world.

So, I’m pleased to report that, using genomic data from more than 5,000 volunteers, our AADM team recently discovered a new gene, called ZRANB3, that harbors a variant associated with T2D in sub-Saharan Africa [1]. Using sophisticated laboratory models, the team showed that a malfunctioning ZRANB3 gene impairs insulin production to control glucose levels in the bloodstream.

Since my first trip to Nigeria, the number of people with T2D has continued to rise. It’s now estimated that about 8 to 10 percent of Nigerians have some form of diabetes [2]. In Africa, diabetes affects more than 7 percent of the population, more than twice the incidence in 1980 [3].

The causes of T2D involve a complex interplay of genetic, environmental, and lifestyle factors. I was particularly interested in finding out whether the genetic factors for T2D might be different in sub-Saharan Africa than in the West. But at the time, there was a dearth of genomic information about T2D in Africa, the cradle of humanity. To understand complex diseases like T2D fully, we need all peoples and continents represented in the research.

To begin to fill this research gap, the AADM team got underway and hasn’t looked back. In the latest study, led by Charles Rotimi at NIH’s National Human Genome Research Institute, in partnership with multiple African diabetes experts, the AADM team enlisted 5,231 volunteers from Nigeria, Ghana, and Kenya. About half of the study’s participants had T2D and half did not.

As reported in Nature Communications, their genome-wide search for T2D gene variants turned up three interesting finds. Two were in genes previously linked to T2D risk in other human populations. The third involved a gene that codes for ZRANB3, an enzyme associated with DNA replication and repair that had never been reported in association with T2D.

To understand how ZRANB3 might influence a person’s risk for developing T2D, the researchers turned to zebrafish (Danio rerio), an excellent vertebrate model for its rapid development. The researchers found that the ZRANB3 gene is active in insulin-producing beta cells of the pancreas. That was important to know because people with T2D frequently have reduced numbers of beta cells, which compromises their ability to produce enough insulin.

The team next used CRISPR/Cas9 gene-editing tools either to “knock out” or reduce the expression of ZRANB3 in young zebrafish. In both cases, it led to increased loss of beta cells.

Additional study in the beta cells of mice provided more details. While normal beta cells released insulin in response to high levels of glucose, those with suppressed ZRANB3 activity couldn’t. Together, the findings show that ZRANB3 is important for beta cells to survive and function normally. It stands to reason, then, that people with a lower functioning variant of ZRANB3 would be more susceptible to T2D.

In many cases, T2D can be managed with some combination of diet, exercise, and oral medications. But some people require insulin to manage the disease. The new findings suggest, particularly for people of African ancestry, that the variant of the ZRANB3 gene that one inherits might help to explain those differences. People carrying particular variants of this gene also may benefit from beginning insulin treatment earlier, before their beta cells have been depleted.

So why wasn’t ZRANB3 discovered in the many studies on T2D carried out in the United States, Europe, and Asia? It turns out that the variant that predisposes Africans to this disease is extremely rare in these other populations. Only by studying Africans could this insight be uncovered.

More than 20 years ago, I helped to start the AADM project to learn more about the genetic factors driving T2D in sub-Saharan Africa. Other dedicated AADM leaders have continued to build the research project, taking advantage of new technologies as they came along. It’s profoundly gratifying that this project has uncovered such an impressive new lead, revealing important aspects of human biology that otherwise would have been missed. The AADM team continues to enroll volunteers, and the coming years should bring even more discoveries about the genetic factors that contribute to T2D.

References:

[1] ZRANB3 is an African-specific type 2 diabetes locus associated with beta-cell mass and insulin response. Adeyemo AA, Zaghloul NA, Chen G, Doumatey AP, Leitch CC, Hostelley TL, Nesmith JE, Zhou J, Bentley AR, Shriner D, Fasanmade O, Okafor G, Eghan B Jr, Agyenim-Boateng K, Chandrasekharappa S, Adeleye J, Balogun W, Owusu S, Amoah A, Acheampong J, Johnson T, Oli J, Adebamowo C; South Africa Zulu Type 2 Diabetes Case-Control Study, Collins F, Dunston G, Rotimi CN. Nat Commun. 2019 Jul 19;10(1):3195.

[2] Diabetes mellitus in Nigeria: The past, present and future. Ogbera AO, Ekpebegh C. World J Diabetes. 2014 Dec 15;5(6):905-911.

[3] Global report on diabetes. Geneva: World Health Organization, 2016. World Health Organization.

Links:

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

Diabetes and African Americans (Department of Health and Human Services)

Why Use Zebrafish to Study Human Diseases (Intramural Research Program/NIH)

Charles Rotimi (National Human Genome Research Institute/NIH)

NIH Support: National Human Genome Research Institute; National Institute of Diabetes and Digestive and Kidney Diseases; National Institute on Minority Health and Health Disparities


A Warm Welcome to African Fellows

Posted on by

I took part in the orientation session for the new African Postdoctoral Training Initiative (APTI) on February 28, 2019. The session was held at the Fogarty Stone House on the NIH campus, and afterwards I joined this inaugural group of APTI fellows and event organizers for a group photo. The orientation, which provided an overview of APTI and its vision to help early-career researchers from Africa excel, was hosted by NIH and its partners in this initiative, the Bill and Melinda Gates Foundation and the African Academy of Sciences. The fellows hail from six African countries, and they will work over the next few years in 10 NIH labs in Maryland, North Carolina, and Montana. Credit: Marleen Van den Neste.

A Scientist and Conservation Photographer

Posted on by

These stunning images of animals were taken by Susan McConnell, whose photographs have appeared in Smithsonian Magazine, National Geographic, Nature’s Best Photography, Africa Geographic, and a number of other publications. But photography is just part of her professional life. McConnell is best known as a developmental neurobiologist at Stanford University, Palo Alto, CA, and an elected member of the U.S. National Academy of Sciences.

How did McConnell find the time while tracing the development of the brain’s biocircuitry to launch a second career as a nature photographer? Her answer: Every research career has its seasons. When McConnell launched her lab in 1989 at the age of 31, she was up to her eyeballs recruiting staff, writing research grants, and pursuing many different leads in her quest to understand how neurons in the brain’s cerebral cortex are produced, differentiated, and then wired together into functional circuits.


Next Page