The week’s most astounding developments from the neobiological frontier.

July 1, 2021

Mini, temporary, re-absorbable pacemakers

Engineers at Northwestern University in Evanston, Illinois, have unveiled a lightweight pacemaker made of biocompatible materials, which they tested on mouse, rabbit, and human heart tissue. Designed to replace bulky temporary pacemakers implanted after heart surgery, the new pacemaker is thin and flexible, and it is made of materials that should reabsorb into the body’s tissues over time. Powered by wireless energy transfer, the single-use pacemakers eliminate the need for batteries and hardware leads, which could lower the risk of infections. Nature Biotechnology

Early trial of CRISPR drug met with investor exuberance

We saw a particularly wild ride this week with Intellia Therapeutics, a 6-year-old company that develops CRISPR-based medicines when its stock doubled in value following new published data on their experimental drug NTLA-2001, to treat people with a rare, progressive, and fatal disease known as transthyretin amyloidosis (ATTR amyloidosis), which is characterized by the accumulation of TTR protein plaques in the heart, liver, and other tissues. Heralded in a company press release as the first ever clinical data supporting the safety of an single dose in vivo CRISPR therapy, the must-buy buzz made the stock one of the key market movers this week, boosting by Thursday’s close other already high-flying gene editing stocks such as Beam Therapeutics (BEAM+30%), Editas Medicine (EDIT +26%), Verve Therapeutics (VERV +32%), CRISPR Therapeutics (CRSP +9%), and Bluebird Bio (BLUE +5%). While the trial was small and these are only phase 1 results, investors needed little convincing. NEJM

New atlas of mouse protein “interactome”

Protein–protein interactions account for much of the nitty gritty of biology, and understanding how complex networks of proteins interact in different cells, tissues, and disease states at various times can both illuminate basic physiology and suggest new targets for drugs. Scientists at the University of British Columbia in Vancouver are reporting an atlas of more than 125,000 protein interactions across seven tissues in mice—more than doubling the current size of the known mouse “interactome.” One thing they found was that proteins involved in particular diseases form sub-networks in the tissues where those diseases manifest, a discovery possibly relevant to drug design. Cell

Polygenic scores for selecting IVF embryos—new hope or new hype?

Embryo selection based on polygenic scores (ESPS) sounds, at first blush, like a good thing—and maybe it is. Calculating the relative genetic risk of poor health outcomes later in life for several embryos and then selecting the “optimal” embryo prior to IVF implantation could reduce diseases like diabetes, Alzheimer’s, heart disease, and cancer. Several companies, including Genomic Prediction, Reprocare Genetics, Orchid Health, and MyOme, are now offering polygenic score selection—with some even offering predictions of outcomes like household income, educational attainment, and “subjective well-being.” But there are major problems in Denmark, according to a group of fertility and genetics experts. The scoring is largely unregulated, and the actual outcomes may not live up to their marketing hype. They are calling for a society-wide conversation and better communication of realistic expectations to future parents—who, after all, only want what’s best for their children. NEJM

Gene therapy after heart attack strengthens coronary tissue in pigs

Surviving a heart attack can be a Pyrrhic victory if it weakens the organ and leads to later heart failure. Now it may be possible to protect people by using gene therapy to induce heart cells to regenerate new tissue and reverse the damage inflicted by the attack, according to researchers at Baylor College of Medicine in Houston, Texas. In a pig experiment, they used viral vectors to deliver short RNA molecules—known as “hairpins” for their characteristic conformation. The hairpins bound to the signaling pathway of a protein called Hippo and dialed down Hippo’s suppression of heart cell growth in adult mammals. Three months after injection, treated pigs had improved left ventricle function, smaller scars on their heart tissue, and greater cell division in the tissue. Science Translational Medicine

A stained section of a pig heart treated with the viral vector 33 days after injection. S. Liu et al., Science Translational Medicine (2021)

The gut bacteria that’s good for your social life

Biologists have known for some time that gut bacteria can affect social behavior. Mice that lack gut bacteria show reduced social behavior, and people with psychosocial disorders have been found to have altered microbiomes, but we have never known exactly how the one affects the other. Now scientists at California Institute of Technology in Pasadena, California, have zeroed in on the bacterium Enterococcus faecalis, which they say promotes social activity through neuronal circuits that mediate the stress response in the mouse brain by reducing corticosterone levels in mice following social stress. Nature

Crafty bacteriophages arm the very bacteria they infect

A provocative new study by researchers at Technical University of Denmark shows that some bacteriophages—viruses that infect bacteria—may be arming the cells they infect with biologically active compounds that confer a survival advantage upon the bacteria (and thus the viruses as well). They found networks of interacting genes called biosynthetic gene clusters in the bacteriophage that work together once inserted inside the bacterial genome to produce bacteriocins, which are toxins harmful to bacteria. The researchers suggest that the presence of these gene clusters in the viral genomes is evidence of the phages’ evolutionary strategy to compete against other local bacteria by basically weaponizing their hosts. Current Biology

Rice-based, room-temp cholera vaccine passes phase 1 clinical trial

Each year, millions of people across the globe fall sick from cholera, and tens of thousands die from the disease. Although effective vaccines exist, they generally require refrigeration, limiting their utility in low-income settings. To address the problem, a team of researchers at the University of Tokyo developed a new oral rice-based vaccine called MucoRice that contains the cholera toxin B subunit. MucoRice doesn’t need to be refrigerated, and it has passed a phase 1 clinical trial, opening the possibility of now vaccinating the communities that don’t have the infrastructure to support a cold supply chain. Lancet Microbe

To sleep, perchance to (day) dream

Maybe you’re reading this and daydreaming, your attention somewhere else. Maybe your mind has gone blank and you forgot what you were thinking about completely. Or maybe you’re simply falling asleep. To the brain, apparently, all three scenarios are almost exactly the same. Psychologists at Monash University in Melbourne, Australia, have measured brain activity via EEG when people’s minds wandered, when they went blank, and when they were falling asleep. The data suggest that attentional lapses in waking life share a common physiology with falling asleep, even when people are fully rested, and that daydreams and mind blanks are just the emergence of sleeplike behavior in the waking brain. The work may someday help suggest ways to help people optimize their attention in educational and work settings. Nature Communications