Scientists Use the Tweaked Genes of a Virus to Halt Vision Loss


What if you could tweak the genes of a virus to turn its ability to invade cells into a delivery system for eyesight therapy? That’s what researchers at Johns Hopkins School of Medicine say they’ve done by modifying an adenovirus, a type of virus that can infect tissue linings. The cutting edge gene therapy was developed to help those who suffer vision loss from a particular eye disorder—wet age-related macular degeneration (AMD).

Approximately 1.6 million Americans have AMD, the number one cause of vision loss. The disease is characterized by the growth of abnormal blood vessels that leak retinal fluid into the eye and destroy the macula, an area near the retina important for high acuity vision. This gene therapy both reduces fluid buildup and improves vision loss in humans, according to study results published in The Lancet.

The best current treatment for the disease requires injections of antibodies into the retina to suppress vascular endothelial growth factor (VEGF), a protein that is responsible for the growth of blood vessels—which in turn cause leaking fluid. But the problem is that patients must obtain these injections at four- to six-week intervals, or else the disease symptoms return and worsen over time. Peter Campochiaro, a professor of ophthalmology and neuroscience at Johns Hopkins Medicine's Wilmer Eye Institute and one of the authors of the study, explains that during this treatment, if a patient takes too long to get their next injection, the abnormal blood vessel net grows larger and recruits other cells. “That scarring causes permanent decrease in vision,” he tells Mental Floss. So over time, it’s common even for patients in treatment to “end up with less vision.”

His team has been working to make a form of injections that last longer, so patients don’t have to come in as frequently. For phase one of this trial, Campochiaro’s team recruited 19 participants to participate in a 52-week study. He was looking for people “who don’t have great visual potential, but have evidence of the disease process that you can measure in effect,” he says.

Since viruses are naturally good at getting into cells and depositing their genetic material, the researchers decided to modify a virus to deposit a gene that codes for a protein called sFLT01. sFLT01 blocks the factor that causes the abnormal vessels and fluid production. When the modified virus is injected into the eye, “the viral vector enters cells and deposits the gene, and the gene begins to produce the [sFLT01] protein,” he says. The protein binds to VEGF, preventing it from causing vessel growth and subsequent fluid leakage.

The 19 participants were divided into five different groups and given increasing doses of the viral vector. After determining there was no toxicity at the dose-limit of the first three groups, they proceeded to increase the dosage to its highest level.

Of the 11 participants with symptoms judged to be reversible, six showed “a substantial reduction in the fluid,” and four of those six saw “a pretty dramatic effect.” Those patients had big pockets of fluid in their retinas decrease, Campochiaro says. Better yet, the treatment lasted throughout the yearlong study, though the protein numbers peaked at 26 weeks, and then declined slightly (although not enough to reactivate disease symptoms).

In assessing why five patients saw no reduction in fluid, the scientists discovered those patients had pre-existing antibodies to the virus. They theorize that in these patients, the immune system may have killed the viral vector before it could deposit the genes, though they will have to do more research to prove this. This could be a problem in using this particular virus—a carrier virus called AAV2—since some 60 percent of patients tend to have these antibodies.

A possible solution might be to give resistant patients a surgical injection instead. During this procedure, scientists could take out the vitreous—a gel-like substance that gives your eye its round shape—and inject the vector surgically under the retina instead. While patients might prefer not to have surgery, “our data suggests that it doesn’t matter if there’s pre-existing antibodies [with this method],” he says.

Alternately, other viral vectors have proven to be more effective than AAV2, including a variation on the virus, AAV8, which provides better infections of the virus into the cell. Even more promising, the researchers recently finished a four-year study on a lentiviral vector (a totally different group of viruses) “that take [the genes] into the nucleus of the cell and inserts the gene right into the chromosomes,” Campochiaro explains.

His next steps will be to retest the treatment with a longer study period to identify just how long-lasting the effects are, as well as to test higher doses of the viral vector.

But right now, he is just excited that the gene therapy works. “We injected this gene, the gene is producing a protein, and you can measure that protein in the eye over time,” he says.

15 Scientific Reasons Spring Is the Most Delightful Season

Summer, winter, and fall may have their fans, but spring is clearly the most lovable of the four seasons. Not convinced? Here are 15 scientific reasons why spring is great:


road and field on a sunny day

Spring marks the end of blistering winter and the transitional period to scorching summer. In many places, the season brings mild temperatures in the 60s and 70s. People tend to be most comfortable at temperatures of about 72°F, research shows, so the arrival of spring means you can finally ditch the heavy winter layers and still be comfortable.


sunny sky

Following the spring equinox, days begin lasting longer and nights get shorter. Daylight Saving Time, which moves the clock forward starting in March, gives you even more light hours to get things done. Those extra hours of sun can be a major mood-booster, according to some research. A 2016 study of students in counseling at Brigham Young University found that the longer the sun was up during the day, the less mental distress people experienced.


blue bird on branch

Many animals migrate south during the winter, then head north as temperatures rise. For relatively northern regions, there is no better indicator of spring than birds chirping outside your window. Their northward migration can start as early as mid-February and last into June, meaning that throughout the spring, you can expect to see a major avian influx. In addition to the satisfaction of marking species off your bird-watching checklist, seeing more of our feathered friends can make you happy. In 2017, a UK study found that the more birds people could see in their neighborhoods, the better their mental health.


Baby squirrels

Many animals reproduce in the spring, when temperatures are warmer and food is plentiful. Baby bunnies, ducklings, chipmunks, and other adorable animals abound come spring. Studies have found that seeing cute animals can have positive effects on humans. For instance, one small study in 2012 found that when college students looked at cute images of baby animals, they were better at focusing on a task in the lab. Being able to watch fluffy baby squirrels frolic outside your office window might make spring your most productive season of the year.


flowers hanging outside of a house

In 2015, a pair of public policy researchers discovered a hidden upside to "springing forward" for Daylight Saving Time. It reduced crime. When the sun set later in the evening, the study published in the Review of Economics and Statistics found, robbery rates fell. After Daylight Saving Time started in the spring, there was a 27 percent drop in robberies during that extra hour of evening sunlight, and a 7 percent drop over the course of the whole day.


child with rainbow umbrella jumping in puddle

Warmer temperatures mean you can spend more time outside without freezing your feet off, which is great for mental health. Across the seasons, research has found that taking walks in nature slows your heart rate and makes you more relaxed, but some research indicates that there is something special about spring's effect on your brain. A 2005 study from the University of Michigan linked spending 30 minutes or more outside in warm, sunny spring weather to higher mood and better memory. But the effect reverses when spring ends, since being outside in the warmest days of summer is usually pretty uncomfortable.


woman writing in a park

That same University of Michigan study found that spending time outside in the sunny spring weather isn't just a mood booster, it actually can change the way people think. The researchers found that being outdoors broadened participants' minds, leaving them more open to new information and creative thoughts.


leaves budding in spring

Spring brings green growth back to plants and trees. Depending on where you live, trees may begin sporting new leaves as early as mid-March. That successful spring leaf growth ensures a cool canopy to relax under during the hot summer—a hugely important factor in keeping cities comfortable. According to researchers, vegetation plays a big role in mitigating the urban heat island effect. When trees release water back into the air through evapotranspiration, it can cool down the areas around them by up to 9°F, according to the EPA.


tulip bulbs

It's amazing what a little sun can do for plants and grass. Through photosynthesis, plants convert sunlight, carbon dioxide, and water into food, releasing oxygen in the process. That means as plants start to grow in the spring, they pull carbon out of the atmosphere, providing an important environmental service. Plants take in roughly 25 percent of the carbon emissions humans produce, absorbing more than 100 gigatons of carbon through photosynthesis each growing season. Because of this, the amount of carbon dioxide in the atmosphere drops each spring and summer. (Unfortunately, it rises in the winter, when most plants aren't growing.)


wooden box full of fresh produce

Many vegetables and some fruits are harvested in the spring. 'Tis the season to get your local asparagus, greens, peas, rhubarb, and other fresh produce. Getting more fruits and vegetables into your diet isn't just good for the body; it's good for the soul. A 2016 study of more than 12,000 Australians found that when people increased the amount of fruits and vegetables in their diet, they felt happier and had higher rates of life satisfaction. If they increased their intake by eight portions a day (a tall order, we know) the psychological gains were equivalent to the change in well-being people experience when they go from being unemployed to having a job, the researchers found.


Flowers in a vase

After months spent conserving energy, flowers bloom in the spring, once they sense that the days have grown longer and the weather has turned warmer. That's good for humans, because several studies have shown that looking at flowers can make you happy. A 2008 study of hospital patients found that having flowers in the room made people feel more positive and reduced their pain and anxiety [PDF]. Another study from Rutgers University found that when participants were presented with a bouquet of flowers, it resulted in what scientists call a "true smile" a full 100 percent of the time. Seeing flowers had both "immediate and long-term effects" that resulted in elevated moods for days afterward, according to the researchers [PDF].


woman tying shoes in flower field

While it's important to keep moving no matter what the weather, research shows that working out can be more beneficial if you do it outside. A 2011 study found that, compared with an indoor workout, exercising outdoors in nature increased energy levels, made people feel revitalized, and decreased tension, among other positive effects. People who worked out in the fresh air also tended to say they enjoyed the experience more and would be likely to repeat it, suggesting that using nature as your gym might help you stick with your exercise regimen. While those benefits probably extend to winter, too, it's a whole lot easier to stomach the idea of a run once the weather warms up.


dew on grass and a daisy

Flu season in the U.S. typically lasts through the fall and winter, usually peaking between December and February and tapering off during the spring. The seasonal change is in part because of dry air. Cold temperatures mean a drop in humidity, and indoor heating only makes the air drier. This lack of moisture in the air can dry out your skin and the nasal cavities, leading to nose bleeds, irritated sinuses, and a greater risk of getting sick. Since the mucus in your nose is designed to trap viruses, when it dries up, you're more likely to catch something nasty, like the flu. As the weather warms up and becomes more humid throughout the spring, that mucus comes back. As the season wears on, not only can you lay off the body lotion, but you can probably put away the tissues—if you don't have spring allergies, that is.


windows open on a red house

Temperate weather makes it easier to get the fresh air you need. Opening your windows and allowing the breeze in serves as an important way to ventilate indoor spaces, according to the EPA. A lack of ventilation can lead to an unhealthy concentration of indoor pollutants from sources like cleaning product fumes, certain furniture and building materials, and stoves (especially gas ones), posing a threat to your health and comfort. Winter brings the highest rates of indoor pollutants like nitrogen oxide, a 2016 study of unventilated stove use in homes found. Spring brings the perfect opportunity to throw open those windows and doors and get the air moving again.


woman enjoying sitting in the sun

Sunlight triggers your body to produce the vitamin D, which keeps your bones strong. At northern latitudes, it's extremely difficult to get enough sun exposure naturally to maintain healthy vitamin D levels during the winter—even if you did want to expose your skin to the elements—but that starts to change during the spring. One Spanish study found that in Valencia (which shares a latitude with Philadelphia, Denver, Baltimore, Kansas City, and several other major U.S. cities), people only need 10 minutes outside with a quarter of their bodies exposed to the spring sunshine to get an adequate daily dose of vitamin D.

A version of this story originally ran in 2014.

8 Ways to Tell If Someone Is Lying to You

Sociopaths and narcissists may believe they have lying down to a science, but it turns out there are a lot of little clues that reveal even the most sophisticated level of mendacity. If you want to catch a liar in their tracks, look for the following "tells," courtesy of father and daughter Dan and Lisa Ribacoff, credibility assessment experts and advanced certified polygraph examiners based in New York. They use their skills in criminal investigations, business matters, family and relationship issues, and other areas; you might have seen them on TV. Dan is also a private investigator.

The Ribacoffs use a mix of psychology, body-language analysis, expert interview skills, and polygraph tests to determine whether someone is lying. A polygraph is a combination of medical devices that monitor any physiological changes, particularly heart rate, blood pressure, respiratory rate, and perspiration rate, that an interview subject undergoes during an interview. To begin this process, the examiner conducts a pretest interview, asking questions that should be easy for the subject to answer, such as name and age. This establishes a "baseline" of normal autonomic responses to benign questions. They may also do a "stimulation test" in which the subject is asked to lie consciously. Changes from the baseline may indicate deception—though that interpretation is up to the examiner.

The accuracy of polygraph tests has been questioned by numerous critics, including the American Psychological Association. Guilty people have passed them, and innocent people have failed them. But they're just one factor in the Ribacoffs' assessments, which are based mostly on reading people, not polygraphs.

Credibility assessment is not built upon a single tell but a combination, Dan tells Mental Floss: "There's not one verbal or non-verbal cue that is going to be the absolute indicator [of a lie]. It's a process of collecting pieces to the puzzle and putting that puzzle together."

Read on for tips to identify when someone might be lying to you.


A common habit for a person obfuscating the truth is to put physical distance between themselves and the person they're lying to, particularly if they're being questioned. "Sitting back and stretching your legs out is trying to gain distance between you and the interviewer," Dan says. Crossing one's arms, a defensive posture, is also a potential sign of duplicity.


Because lying activates the limbic system, whose goal is to keep you calm under stress, liars may have a hard time sitting still. "It's like the popcorn maker pops its lid [in your mind]," Dan says. "You do things to burn off nervous energy, like pick off imaginary lint, rub your arm—self-soothing behaviors such as moving or fidgeting." Lisa tells Mental Floss that "rubbing your neck or playing with hair" are also signs of potential deception, particularly if someone does it right after they lie to you.


man in suit avoids eye contact

Eye contact is intimate, vulnerable—and lots of liars can't hold a gaze when they're working up a mistruth. Lisa says she's found that examinees will often maintain eye contact "right up until they give the answer they're lying about." The polygraph usually reveals physiological changes that suggest the person is lying. There are other reasons that a person might not make eye contact, such as being on the autism spectrum or having certain psychological disorders, but Dan says the baseline of normal behavior is established for each individual subject. What examiners look for is a change or departure from the person's unique baseline.


A liar will not directly say they haven't done something wrong; they'll answer with a dodge, a question back at you, or a nonsequitor. Not answering directly is an immediate alarm bell to Dan. An innocent person will usually just say "no" when asked if they've done something wrong. "A guilty person has a hard time saying no," Dan says. When they don't answer the question, you might sniff out a lie.


Hand pointing

Another surefire trick of the treacherous is to over-explain. "They hard sell it to you, they go off on tangents, they ramble," Dan says. "They give you unimportant information." Or, they'll shift the blame onto someone else.

Dan, who lends his expertise to The Steve Wilkos Show, recently assessed a situation where an employee of a hotel was accused of stealing money from a hotel room. He polygraphed the entire hotel security staff, because it involved taking money from a safe that only they would have access to. When Dan questioned the accused employee, the man proclaimed his innocence and shifted the blame to his manager, Kara, and another employee named John. "When I said, 'Did you take the money?' he said, ‘I didn't take the money, it's that goddamn Kara, she's constantly favoring this one guy John because she grew up with him, and he's her boy,'" Dan recalls.

But John passed the polygraph, while the employee—who was guilty—failed it.


Liars also tend to change the story every time they tell it. In a recent case, Dan interviewed a man who was charged with stealing from his workplace and selling the items. He claimed to Dan that a security guard at the company had actually committed the crime. He even mentioned that he'd run into the security guard recently at a party. But conveniently, the man didn't know the guard's name or have his phone number. Lisa put him through a second interview, asking him the same questions, and "suddenly he knows the security guard's name and has his number," she says. This spelled a lie to Dan, and the polygraph results backed up his assessment.


"If the story doesn't make sense, it's usually not true," Dan says. In a recent case, a wife had agreed to take a polygraph at the request of her jealous husband, who had found numerous texts between her and a coworker on her phone. At first she told Dan that she and her colleague were merely friends who texted a lot, but that nothing physical happened between them. But as the polygraph went on, she added their communications went on for three years … and then confessed that they included nude photos of her.

She failed the polygraph—but then agreed to a second one, during which she denied having sexual contact with the friend. After she failed that test too, she admitted she had kissed the friend. (Even without these confessions, her body language throughout both tests was telling, Dan says; she was distraught and trembling. "I felt really bad for her," he admits. "I knew it wouldn't end well.")

"There's a saying: If it doesn't add up," Dan says, "it's usually because the truth wasn't in the equation."


Close-up of perspiring, tense, frowning young blonde woman

You breathe shallower when you lie, your face flushes, and you may begin to sweat. In addition, Dan says, "You lick your lips because digestion stops when fight or flight kicks in." Of course, these symptoms can also happen if you are genuinely afraid or have issues with authority, but according to Dan, this is where that valuable baseline of behavior helps an examiner determine if you were already nervous when you walked in.

Dan has one more tip that's useful no matter how astute your observational powers are: Get the person talking. He suggests approaching your line of questioning as an interview rather than an interrogation. "When I interview you, I let you talk," he notes. "In an interrogation, I'm doing the talking to get you to confess."


More from mental floss studios