Research advances from the National Institutes of Health (NIH) Intramural Research Program (IRP) often make headlines. Read the news releases that describe our most recent findings:
For the first time, scientists have used gene therapy to correct defective structures in the inner ears of newborn mice, according to results of a new study by researchers from the National Institute on Deafness and Other Communication Disorders (NIDCD), part of the National Institutes of Health. The mice had a type of hereditary deafness also found in humans.
Hair cells are small sensory cells of the inner ear that transform sound vibrations into nerve impulses. After sound waves enter the inner ear’s cochlea, they produce waves in a fluid layer. The waves lift the overlying hair cells, and bend tiny hair-like structures on the hair cell surfaces—called stereocilia—by driving them into an overlying membrane. Bending the stereocilia triggers an electrical signal that is sent to the brain and interpreted as sound.
An international team of scientists co-led by researchers from the National Heart, Lung, and Blood Institute (NHLBI) is reporting the discovery of nearly 1,500 age-related genes, most of which have not been previously identified. The study, one of the largest of its kind to explore genes associated with aging, could spark new insights into the aging process and age-related chronic diseases, including heart disease, cancer, and stroke. The findings could, for example, provide new targets for developing drugs to delay or prevent age-related diseases. The study, which is partly funded by the NHLBI, appears in the online issue of Nature Communications.
New Cas enzymes shed light on evolution of CRISPR-Cas systems
An international team of CRISPR-Cas researchers has identified three new naturally-occurring systems that show potential for genome editing. The discovery and characterization of these systems is expected to further expand the genome editing toolbox, opening new avenues for biomedical research. The research, published today in the journal Molecular Cell, was supported in part by the National Institutes of Health.
“This work shows a path to discovery of novel CRISPR-Cas systems with diverse properties, which are demonstrated here in direct experiments,” said Eugene Koonin, Ph.D., senior investigator at the National Center for Biotechnology Information (NCBI), National Library of Medicine (NLM), part of the NIH. “The most remarkable aspect of the story is how evolution has achieved a broad repertoire of biological activities, a feat we can take advantage of for new genome manipulation tools.”
Recent research has yielded new information about immune responses associated with—and potentially responsible for—protection from HIV infection, providing leads for new strategies to develop an HIV vaccine. Results from the RV144 trial, reported in 2009, provided the first signal of HIV vaccine efficacy: a 31 percent reduction in HIV infection among vaccinees. Since then, an international research consortium has been searching for molecular clues to explain why the vaccine showed this modest protective effect.
A new review outlines findings that hint at the types of immune responses a preventive HIV vaccine may need to induce. The article was co-authored by leaders in HIV vaccinology, including Anthony S. Fauci, M.D., director of the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health, and lead author Lawrence Corey, M.D., of the Fred Hutchinson Cancer Research Center.
Surveys show 9.5 percent of Americans use marijuana; 30 percent of users meet criteria for a disorder
The percentage of Americans who reported using marijuana in the past year more than doubled between 2001-2002 and 2012-2013, and the increase in marijuana use disorder during that time was nearly as large. Past year marijuana use rose from 4.1 percent to 9.5 percent of the U.S. adult population, while the prevalence of marijuana use disorder rose from 1.5 percent to 2.9 percent, according to national surveys conducted by the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of the National Institutes of Health.
“Based on the results of our surveys, marijuana use in the United States has risen rapidly over the past decade, with about 3 in 10 people who use marijuana meeting the criteria for addiction. Given these increases, it is important that the scientific community convey information to the public about the potential harms,” said George Koob, Ph.D., director of NIAAA.
Scientists at the National Institutes of Health (NIH) have created a protein that awakens resting immune cells infected with HIV and facilitates their destruction in laboratory studies. The protein potentially could contribute to a cure for HIV infection by helping deplete the reservoir of long-lived, latently HIV-infected cells that can start making the virus when a person stops taking anti-HIV drugs. Further studies in animals and people are needed to determine the viability of this approach.
Illustration of how the engineered protein facilitates destruction of latently HIV-infected immune cells. 1) Protein and cells, from left to right: engineered protein with yellow-and-black CD3-binding end and thick black HIV-binding end; latently HIV-infected helper T cell (blue); inactivated killer T cell (red). 2) Protein binds to CD3 receptor on helper T cell, activating it so the helper T cell starts making HIV and displaying pieces of virus (red) on its surface. 3) Protein binds to HIV fragment on helper T cell and CD3 receptor on killer T cell, activating the killer T cell and bringing the two cells close together. 4) Activated killer T cell destroys HIV-infected helper T cell.
Drug-resistant forms of Plasmodium falciparum, the deadliest species among malaria parasites, are able to infect the type of mosquito that is the main transmitter of malaria in Africa, according to findings from scientists at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, and global partners. The discovery suggests Africa—where malaria will cause an estimated 400,000 deaths in 2015—is more at risk for drug-resistant malaria infections than previously thought, which could further compromise efforts to prevent and eliminate the disease.
A Cambodian Anopheles mosquito taking a blood meal. Credit: NIAID
Many types of modern biomedical microscopes use pulses of light aimed at chemical probes to image proteins, membranes, and cell structures. New understanding of biological processes within living tissues, such as metabolism and DNA repair, rely on the work researchers have done to bring miniscule features into focus. Their techniques include mastery of sophisticated instruments and software, as well as the development of genetically encoded fluorescent proteins, called fluorophores.
“As great as some of the current instrumentation is, much is limited by the physics of light and fluorophores,” explained George Patterson, Ph.D., investigator in the Section on Biophotonics at the National Institute of Biomedical Imaging and Bioengineering (NIBIB), part of the National Institutes of Health. “We are always bumping up against resolution limits.”
Two studies in mice use new technique to provide insight into cell development critical for hearing, balance
Using a sensitive new technology called single-cell RNA-seq on cells from mice, scientists have created the first high-resolution gene expression map of the newborn mouse inner ear. The findings provide new insight into how epithelial cells in the inner ear develop and differentiate into specialized cells that serve critical functions for hearing and maintaining balance. Understanding how these important cells form may provide a foundation for the potential development of cell-based therapies for treating hearing loss and balance disorders. The research was conducted by scientists at the National Institute on Deafness and Other Communication Disorders (NIDCD), part of the National Institutes of Health.
Favipiravir, an investigational antiviral drug currently being tested in West Africa as a treatment for Ebola virus disease, effectively treated Lassa virus infection in guinea pigs, according to a new study from National Institutes of Health (NIH) scientists and colleagues.
