#ethnobiology

“Border fragment of wool with a continuous band of #hummingbirds and fringelike appendages representing beans. Early Nasca [Nazca, Peru, c.1-450 CE]. Pollination of bean plants by birds may be suggested here. Border was formed using a needle-knit stemstitch.”

Imagine a microscopic factory that lives inside you—not a robot, but a worm. Researchers at Washington University School of Medicine have genetically modified hookworms so they can manufacture & secrete human medicines directly inside a host's body. This isn't speculative—it's already been done in animals. Scientists inserted a human antibody gene into the hookworm genome, which consists of 18,766 genes, & proved that the worm could produce & release the antibody against tetrodotoxin (TTX), which is an extremely potent neurotoxin that can cause paralysis & death even in small amounts. The toxin is found in the pufferfish, which is considered a delicacy, especially in Japan. Unfortunately, if not cleaned & prepared properly, it can (and has) caused several deaths. In any case, even after TTX was administered to the hamsters, the engineered worms secreted a human single-chain antibody fragment that neutralized TTX in the hamsters' bloodstream.

The scientists first had to find a specific spot on the hookworm's DNA where the gene would be safe & active to modify. They chose GSH2 (genomic shorthand for "genomic safe harbor 2"). "2" stands for the 2nd such site they've identified so far. Why is it "safe"? Think of the worm's DNA as a city full of buildings. If you randomly drop a new building (a new gene) somewhere, you might knock out a hospital, block a power plant, or cause traffic chaos. GSH2 is a "pre-vetted empty lot" or "safe harbor" because nothing essential is there; you can safely insert a gene & the body will still run smoothly. This is the site where they inserted the "human medicine gene," s16-HuScFv, which stands for "human single-chain variable fragment," a compact version of a human antibody. To make the gene pump out antibodies into the human host's gut, where it can enter the bloodstream, they added a natural molecule hookworms use to export proteins called ASP-1, which stands for Ancylostoma Secreted Protein-1. The attached antibody gene is like a shipping label, telling the worms' cells to send this product outside, so the worm ends up pumping the antibody where it is needed.

How do the hookworms know where to go? Hookworms already have a built-in GPS finding their way to the small intestine (their natural habitat), & once there, they attach to the intestinal wall & release molecules into the host's circulation. Theoretically, scientists could swap the tetrodotoxin antibody for any therapeutic molecule, such as the insulin gene, to treat diabetes. The worm acts like a living insulin pump. The worm could release natural anti-inflammatory proteins to treat or calm autoimmune diseases. In terms of treating or curing food allergies, the worm could pump out allergen-desensitizing peptides, training the immune system to "chill out." Theoretically, the worms can even become a built-in antidote factory to neutralize toxins or viruses. Hookworms are tiny (0.4 in/1 cm), long-lived, & have naturally coexisted with humans for tens of thousands of years, dating back to when our ancestors first walked barefoot in tropical soils. Their immune-modulating secretions already help reduce inflammation—hence trials for celiac disease & ulcerative colitis.

Are they safe within you? Yes, because they cannot reproduce inside a host; they need soil to complete their cycle. Adults lay eggs that exit via feces. Without soil & oxygen, they die. The insertion of hookworms uses attenuated (weakened) or sterile strains. The worms are engineered to secrete medicine, not to feed aggressively. Their numbers are kept minimal—a few dozen, not thousands. They are monitored & easily removable with antiparasitic drugs if needed. If you ever saw the great sci-fi film The Fantastic Voyage, where humans were miniaturized & injected into a host's body to fix problems, this is the same idea except it's real biology, not science fiction. The next step in this real sci-fi drama is trials in larger animals than Syrian hamsters, followed by humans, focusing on safety & dosage control. Hamsters were chosen because their intestines mimic human physiology closely enough for testing. The worms survived, secreted antibodies & neutralized a very powerful toxin—strong proof that the concept is viable.

Yes, believe it or not, kids in Bavaria, Germany; the Austrian Alps; Czechia & Slovakia; Hungary; & parts of Poland put a straw on an anthill, wait for the ants to crawl over it, and then suck it for its sour taste. The sour taste comes from formic acid, which ants make by converting serine (an amino acid) into formic acid through enzymes. The acid accumulates in a specialized reservoir called the poison sac, which they spray after raising their abdomen, aiming, & firing. It feels like a sharp nettle sting. The practice does not continue today. I was recently asked whether this is why this student's mother, who apparently engaged in this practice, lived until 93. I answered that many people have lived to 93 without ever sucking on an ant-infested straw. And undoubtedly, many people engaged in this behavior without making 93.

Folklore in some European countries held that it is indeed a remedy for aging. The rationale behind this is that ants are tireless workers, able to carry 10-50x their weight; that's like a 180 lb (82 kg) human lifter casually deadlifting a small car. If you weighed 150 lb (68 kg), ant-style, you'd walk home carrying 3,000 lb of groceries without stopping or tiring. It was believed that by sucking on an ant's straw, their vitality would be transferred to the straw sucker. In science, such beliefs are known as "sympathetic magic," with "sympathy" in this instance meaning "sharing," and "magic" implying a supernatural effect. The straw was believed to absorb the ants' life force & transfer it to the air inside the straw, where it would make its way into the body of a person seeking enhanced health & dynamism.

Other examples of sympathetic magic in history were the consumption of a lion's heart for courage, eating animal testicles for virility, and drinking bone meal broth for skeletal strength. In the 16th century, Philippus Aureolus Theophrastus Bombastus von Hohenheim, better known as Paracelsus, meaning "beyond Celsius," positioned himself as surpassing the Roman medical authority Aulus Cornelius Celsus. (Don't you just love those names?) Paracelsus systematized & popularized another form of sympathetic magic known as the Doctrine of Signatures. The theory maintains that God placed "signatures," or medical clues, in plants; for example, walnuts being brain-shaped must be good for the brain; yellow plants are a sign from God as treatment for jaundice; and liverwort would treat liver disease, & heart-shaped leaves from linden or basswood, redbud, violet, wild ginger, coltsfoot, & hota have all been associated with healing the heart. Rhinoceros horn, for obvious reasons, could treat ED (erectile dysfunction).

As for the ant connection, American humorist and poet Ogden Nash, who wrote like a scientist who moonlighted as a stand-up comic, once cleverly noted, "The ant has made herself illustrious by constant industry, industrious. So what? Would you be calm and placid if you were full of formic acid?" Formic acid's name derives from the Latin for "ant." Soldier ants use formic acid to mask the scent of pheromones that enemy ants lay down to mark trails that guide their confreres to food. Should an ant be angered after being molested with a straw, it could prompt them to release formic acid. But the amount of formic acid deposited by ants walking on a straw is microscopic, enough to taste sour but not enough to burn. It has no health benefits but sometimes can cause a mild skin rash.

There is, however, a proven useful benefit to the straw-infested ants. Instead of sticking that straw in the mouth, you could stick it... (no, not there). But sticking it into 3-6 oz of warm milk (90-180 ml) and waiting 12-24 hours will reliably produce an ant yogurt. The origins of ant yogurt trace back to Türkiye around 8,000 years ago & Bulgaria to around 1,000 BCE. Both countries used redwood ants, and that's because they are the champions when it comes to formic acid production, with one of the highest concentrations in the insect world. Conversion of milk to yogurt requires bacteria that produce lactic & acetic acids that then cause milk proteins to precipitate & provide enzymes to convert some of the proteins & fats and sugars that are found in milk to produce flavorful compounds. Redwood ants carry starters called fructolactobacillus sanfranciscensis. The bacteria are famous for the delightful flavor of San Francisco sourdough bread.