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Scientists are looking for a new way to make antivenom and a new study poked some holes in a diagnostic test by making volunteers drink their own blood.

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It’s tempting to think that doctors are on the cutting edge of medical science, but some advancements take a while. Like this week, a paper was published in Nature Communications that announced progress toward a more effective antivenom for the super toxic black mamba.

This snake’s venom has a few kinds of potent neurotoxins that act in the bloodstream and mess up the nervous system. Without treatment, a bite from one of these danger noodles can cause drowsiness, stopped breathing, and paralysis, eventually resulting in death in as little as half an hour. Now, the antivenoms that we currently have neutralize toxins by binding antibodies to them, making them harmless.

These antivenoms are made by injecting a bit of black mamba venom into large animals, usually horses, so their immune systems develop antibodies for the toxins. Then, we extract their blood plasma, process it with a variety of chemicals and filters, and there’s a treatment. But there are some side effects that researchers are trying to cut down on, like nausea, low blood pressure, skin rashes, or swelling.

I mean, if you succeed at not dying, it’s probably a price you’re willing to pay. As of now, researchers still aren’t totally sure what causes the side effects. But they hope that antibodies derived from humans will be more compatible with our immune systems and reduce them.

And recently, scientists tested different treatments in mice. They injected mice with either isolated neurotoxins or complete black mamba venom, and either individual human antibodies or combinations of a few. They found out two big things from all these experiments.

The first is that human antibodies can effectively neutralize at least some lethal neurotoxins inside of a living animal. And the second is that antivenoms that used multiple types of antibodies were more effective. In the end, the most effective cocktail involved three specific human antibodies.

It could protect against typically lethal doses of venom, even when everything was injected straight into mice brains. Now, this kind of study is a proof of concept. Researchers still have to do more work and make sure enough toxins are neutralized with these antivenom mixtures to prevent death.

So we’re not about to jump into human trials, but it’s a start. While medical researchers are always searching for ways to treat diseases, they’re also coming up with better ways to find diseases. And sometimes, they can get a little creative.

One study that really stepped it up is currently making the news online. It’s actually called “The Vampire Study” and was published this past August in the United European Gastroenterology Journal. These researchers were trying to learn more about how to test for Inflammatory Bowel Disease, or IBD.

And to do that, they had subjects drink their own blood. IBD is a term that encompasses both Crohn’s disease and ulcerative colitis, both conditions that feature chronic inflammation in the intestines. And it’s potentially on the rise.

These conditions can have lots of different symptoms that vary between patients, like pain, low energy, or diarrhea. So diagnoses are tricky, and doctors use multiple tests to make sure they’re accurate and monitor how the disease is changing. The gold standard is to attach a camera to a long tube, stick it in the patient’s body, and have a look around.

But this process, called an endoscopy, is invasive and can be uncomfortable. So researchers are hoping to find some kind of marker in poop that could be used alongside endoscopies to diagnose and monitor IBD. Ideally, this could also act as a screening test so people who have other bowel diseases can skip the scope.

One of the best candidates for a marker so far is fecal calprotectin, a protein commonly found during inflammation. It’s super present in neutrophils, one of the cells involved in the early immune response. So the thought was: more calprotectin, more inflammation.

And in healthy patients, doctors shouldn’t find much calprotectin, like, below 50 micrograms per gram of poop. So it sounds like a simple yes or no test for IBD, but there is a problem. If a patient has any bleeding in their upper digestive system, more calprotectin might show up in their stool.

And while any bleeding is bad, it can be a symptom of many different conditions. So if you’re a doctor trying to diagnose IBD or watch for inflammation flare ups, you want a positive test result to mean one clear, specific thing. Which this test might not.

So these researchers were trying to figure out how much blood would raise calprotectin levels above that 50 microgram per gram threshold. They tested this by having 16 healthy subjects drink either 100 or 300 milliliters of their own blood. Then a month later, they drank the other volume.

The researchers collected daily poop samples from 2 days before to 7 days after patients drank blood, plus an extra checkpoint after 2 weeks. And the levels of calprotectin in poop did increase. 7 of the subjects got above that threshold at some point after drinking 100 milliliters of blood, while 10 did after drinking 300 milliliters. This means that if a doctor is using a calprotectin test for IBD, some bleeding in your upper gut could lead to a positive diagnosis even if you don’t have it.

The researchers suggested that looking at the amount of calprotectin might be important to refine these tests. Because a significant IBD flare-up can result in over 200 micrograms per gram. And these conclusions are still important in medicine.

Experts need to refine their tools to make the best call they can. Thanks to for supporting this episode. Brilliant offer interactive lessons and quizzes in math and science.

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