Astronomers developed a “guide star” adaptive optics technique to obtain the most crystal-clear and precise telescopic images of distant galaxies, stars and planets. Now a team of scientists, led by Nobel laureate Eric Betzig, PhD, are borrowing the very same trick. They’ve combined it with lattice light-sheet to create a new microscope that’s able to capture real-time, incredibly detailed and accurate images, along with three-dimensional videos of biology on the cellular and sub-cellular level.
The work — a collaboration between researchers at Howard Hughes Medical Institute, Boston Children’s Hospital and Harvard Medical School — is detailed in a new paper just published in Science.
“Every time we’ve done an experiment with this microscope, we’ve observed something novel — and generated new ideas and hypotheses to test,” Kirchhausen said in a news story by HMS. “It can be used to study almost any problem in a biological system or organism I can think of.” …
Ribonucleic acid, or RNA, has long been underappreciated for its role in gene expression. Until recent years, RNA has been thought of merely as a messenger, shuttling DNA’s instructions to the genetic machinery that synthesizes proteins.
But new discoveries of RNA functions, modifications and its ability to transcribe sections of the genome that were previously considered “junk DNA” has led to the discovery of a huge number of new druggable targets.
These new insights into RNA’s complex purposes have largely been uncovered through ever-increasingly sensitive and affordable sequencing methods. As a result, RNA-based drugs now stand to greatly extend our ability to treat diseases beyond the scope of what’s possible with small molecules and biologics.
Lieberman, who has helped pioneer the RNA-based drug revolution herself, was the first scientist to show in an animal disease model that small, double-stranded RNAs could be used as drugs and leveraged to knock down genes in cells.
Cells throughout the human body are constantly being damaged as a part of natural life, normal cellular processes, UV and chemical exposure and environmental factors — resulting in what are called DNA double-strand breaks. Thankfully, to prevent the accumulation of DNA damage that could eventually lead to cell dysfunction, cancer or death, the healthy human body has developed ways of locating and repairing the damage.
Unfortunately, these DNA repair mechanisms themselves are not impervious to genetic errors. Genetic mutations that disrupt DNA repair can contribute to devastating disease.
Across the early-stage progenitor cells that give rise to the human brain’s 80 billion neuronal cells, genomic alterations impacting DNA repair processes have been linked to neuropsychiatric disorders and the childhood brain cancer medulloblastoma. But until now, it was not known exactly which disruptions in DNA repair were involved.
The human body’s innate immune system employs a variety of “sensors” for identifying foreign invaders such as viruses. One such viral sensor is a receptor called MDA5, found in every cell of the body.
Inside each cell, MDA5 constantly scans genetic material, checking if it’s native to the body or not. As soon as MDA5 identifies the genetic signature of a viral invader, it trips a system-wide alarm, triggering a cascade of immune activity to neutralize the threat.
But if a genetic mutation to MDA5 causes it to confuse some of the body’s own genetic material for being foreign, “false alarms” can lead to unchecked inflammation and disease. Scientists from Boston Children’s Hospital have discovered a new link between MDA5’s ability to discriminate between “self” and “non-self” genetic material — called RNA duplexes — and a spectrum of autoimmune disorders. …
To fight HIV, the development of immunization strategies must keep up with how quickly the virus modifies itself. Now, Boston Children’s Hospital researchers are developing models to test HIV vaccines on a faster and broader scale than ever before with the support of the Bill & Melinda Gates Foundation.
The researchers are racing against HIV’s sophisticated attack on the human immune system. HIV, the human immunodeficiency virus, mutates much faster than other pathogens. Within each infected patient, one virus can multiply by the billions. …
Immune cells called “killer cells” target bacteria invading the body’s cells, but how do they do this so effectively? Bacteria can quickly evolve resistance against antibiotics, yet it seems they have not so readily been able to evade killer cells. This has caused researchers to become interested in finding out the exact mechanism that killer cells use to destroy bacterial invaders.
Although one way that killer cells can trigger bacterial death is by inflicting oxidative damage, it has not yet been at all understood how killer cells destroy bacteria in environments without oxygen.
Now, for the first time, researchers have caught killer cells red-handed in the act of microbial murder …
WATCH: DNA nanoswitches change shape in the presence of biomarkers. The shape change is revealed in a process called gel electrophoresis. Credit: Wyss Institute at Harvard University
“Nanoswitches” — engineered, shape-changing strands of DNA — could shake up the way we monitor our health, according to new research. Faster, easier, cheaper and more sensitive tests based on these tools — used in the lab or at point of care — could indicate the presence of disease, infection and even genetic variabilities as subtle as a single-gene mutation.
“One critical application in both basic research and clinical practice is the detection of biomarkers in our bodies, which convey vital information about our current health,” says lead researcher Wesley Wong, PhD, of Boston Children’s Hospital Program in Cellular and Molecular Medicine (PCMM). “However, current methods tend to be either cheap and easy or highly sensitive, but generally not both.”
A newly-unveiled discovery, four years in the making, could change the way we look at autoimmune diseases and our understanding of how and why immune cells begin to attack different tissues in the body.
“Once your body’s tolerance for its own tissues is lost, the chain reaction is like a runaway train,” says Michael Carroll, PhD, of Boston Children’s Hospital and Harvard Medical School (HMS). “The immune response against your own body’s proteins, or antigens, looks exactly like it’s responding to a foreign pathogen.”
A team led by Carroll has spent years investigating mouse models of lupus to better understand the ins and outs of autoimmune diseases. Its latest findings, published in Cell, reveal that rogue B cells — immune cells that produce antibodies and program the immune system to attack certain antigens — can trigger an “override” that launches the body into an autoimmune attack. Adding insult to injury, B cells’ immune targeting instructions can rapidly expand to order an attack on additional tissue types within the body. …
We are normally born with a highly sophisticated array of molecules that act as “sentries,” constantly scanning our bodies for injuries such as cuts and bruises. One such molecular sentry, known as von Willebrand factor (VWF), plays a critical role in our body’s ability to stop bleeding.
To prevent hemorrhage or life-threatening blood clots, VWF must strike a delicate balance between clotting too little or too much. Researchers have long suspected that the mechanical forces and shear stress of blood flow could be closely-related to VWF’s function.
“In some ways, like in the movie Star Wars, VWF may be considered a Jedi knight in our body that can use ‘the force’ to guard the bloodstream,” says Timothy Springer, PhD, of Boston Children’s Hospital and Harvard Medical School (HMS).
It has not been possible to witness exactly how VWF senses and harnesses these mechanical forces — until now. …
A biological process known as genomic imprinting helps control early mammalian development by turning genes on and off as the embryo and placenta grow. Errors in genomic imprinting can cause severe disorders and profound developmental defects that lead to lifelong health problems, yet the mechanisms behind these critical gene-regulating processes — and the glitches that cause them to go awry — have not been well understood.
Now, scientists at Harvard Medical School (HMS) and Boston Children’s Hospital have identified a mechanism that regulates the imprinting of multiple genes, including some of those critical to placental growth during early embryonic development in mice. The results were reported yesterday in Nature.
“A gene that is turned off by epigenetic modifications can be turned on much more easily than a gene that is mutated or missing can be fixed,” said Yi Zhang, PhD, a senior investigator in the Boston Children’s Program in Molecular and Cellular Medicine, a professor of pediatrics at HMS and a Howard Hughes Medical Institute investigator. “Our discovery sheds new light on a fundamental biological mechanism and can lay the groundwork for therapeutic advances.” …