Bloody harvest
by Alexis C. Madrigal, The Atlantic
Each year, up to half a million horseshoe crabs are trapped and bleeding to create a unique biomedical technology.
Frame from the PBS Nature documentary film - Two types of catastrophe
')
The first thought that comes about the blood of the horseshoe crab is blue, sky blue.
But the most remarkable feature of the blood of the horseshoe crabs is not the color. This is a chemical compound found only in amoebocytes of their blood cells, which is able to detect traces of bacteria and seize them in an irreversible thrombus.
To use this biological idiosyncrasy, pharmaceutical companies break down cells containing this substance, called a coagulogen. They can then use coagulogen as a contamination detector in any solution that may come in contact with blood. If dangerous endotoxins of bacteria are found in a liquid — even if their concentration is one part per trillion — the bloodtail's blood extract will set to work, turning the solution into what scientist Fred Bang, co-author of the discovery, called “gel.”
“It immobilizes bacteria but does not kill them.” - Bang wrote in 1956 in a work describing a substance. "The gel or clot was stable and sticky and remained so for several weeks at room temperature."
If there is no bacterial contamination, then coagulation does not occur, and a decision can be made that no bacteria are present. This is a simple, near-instant test called LAL , LAL , or Lime Amoebocyte Limulus. The test is named for the crab species, Limulus polyphemus.
The LAL test replaced a rather large number of horrific studies with all sorts of pollutants (large rabbit colonies) . Pharmaceutical companies do not like working with rabbits, among other things, because it is a slow and expensive process.
To date, testing with the help of the blood of a horseshoe crab has become a big business. “Every FDA-certified medical product (Food and Drug Administration, US Food and Drug Administration) must be tested with LAL.” The PBS Nature documentary says , “including surgical implants, such like pacemakers and prostheses. "
I don’t know how about you, but the thought that every person in America who has ever been injected was protected from bacteria because we collect the blood of invisible sea creatures with hidden chemical superpowers — I’m not a bit uncomfortable with this thought. This is not even from the script for the sci-fi film, it is postmodernism.
The only problem is that companies need large amounts of horseshoe crabs. Horseshoe whales inhabit the seabed, near the coastline. When they wish to mate, they swim in shallow water, and crabs catchers, standing at the bottom, snatch them from their native habitat.
Fishermen working for biomedical companies are not the first to come up with catching horseshoe crabs. Returning to the days of colonial America, "shell fertilizer" was used to enrich the fields. In the 20th century, even organized industry appeared in Delaver Bay. The shells of the horseshoe crabs evaporated and then were buried to feed the agricultural fields. Others went to feed for pigs. The number of crabs caught was estimated in the millions.
horseshoe crabs collection for fertilizer production, 1928. (Delaware State Archives)
Due to the fact that we slowly destroyed the horseshoe crabs population, by the 1970s, the fertilizer industry from their shells had shrunk and disappeared. But the catch resumed in the 1990s, when the fishermen realized that they could use the horseshoe crab as bait for fishing. Including large mollusks, buccions and river eels.
In other words, these animals did not feel the friendliness of the people. They were not spoiled by the type of affection we endowed with, for example, tame rabbits. In the eyes of the people before the work of Fred Bang, the only virtue of the horseshoe crabs was their accessibility. They love the seashore, as we do.
And because of the high level of bacteria in this habitat, according to the assumption of Bang, the horseshoe crabs acquired their amazing chemical protection. Their circulatory system is more like a spider’s circulatory system than ours. If we inhale anything bad, this thing passes through our body and blood veins, having the unpleasant effects of communicating with white blood cells all the way. But if the bacteria make their way through the exoskeleton of the horseshoe crab, they can move freely causing harm.
“The presence of large sinuses allows blood to directly contact the tissues,” explains the history of the crab at the Woods Hole Oceanographic Institute. “There are a large number of large open cavities and bacteria, penetrating into the gaps in the shell of the horseshoe crab, easily enter the internal areas of the crab, presenting a potentially killer scenario.”
Coagulogen changes the admission mode in the bloodstream of the horseshoe crab. When crab blood cells feel invaded, they release granules with a chemical that becomes a sticky physical barrier to the movement of bacteria, preventing infection from spreading. The best metaphor would be the Ice Man's Super -Force from the X-Men movie , but instead of using cold to eliminate its enemies, the horseshoe crabs use their amazing chemical abilities.
These abilities, unfortunately, of the horseshoe crabs, are absent in humans.
After the crabs collectors deliver them to the laboratory, they pierce the tissue in the region of the hearts of animals and collect up to 30 percent of the animal's blood. Amoebocyte extract (LAL) is obtained from blood, its possible cost in the market reaches $ 15,000 per quart. Only five companies take blood from crabs: Associates of Cape Cod , Lonza , Wako Chemicals , Charles River Endosafe , and Limuli Labs (which do not have a website)
The horseshoe crabs are returned to the ocean far from the place where they were caught - to warn of the exsanguination of animals. The whole process takes from 24 to 72 hours.
Industry representatives report that a small number of animals are dying. However, about 10-30 percent of the total number of animals that bleed, actually die. This can be compared to how we donate blood. Crabs take apple juice, eat sweet cookies and soon return to normal.
But some experts point out problems. In areas where horseshoe crabs are harvested in large quantities for biomedical purposes, such as Pleasant Bay and Massachusetts, females spawn less and less. Perhaps the selection of blood, technically speaking, spoils them, if not even leads to death.
Researchers at the University of New Hampshire and Plymouth State University decided to test this hypothesis. They attached accelerometers to the horseshoe crab females, who shed blood for the good of our society.
horsetail equipped with an accelerometer
They described the results of a study in a new article in The Biological Bulletin, “The sublethal behavioral and psychological effects of the biomedical blood drawing process of the horseshoe crab, Limulus polyphemus.”
The process of blood sampling, as it turned out, makes bloodless animals more apathetic, slower and less willing to follow the tides, as is customary in their relatives.
“The changes that we observe in the degree of mobility, speed of movement, and exposure to tidal rhythms can have a detrimental effect on the daily activity of L. polyphemus, which is particularly associated with the roar throwing season,” they said. “Spawning necessitates several energy-intensive migrations to the tide strip, this is more true for females who can travel to the tide strip several times a week. A lack of activity, for example caused by blood sampling, can affect the number of such migrations or their duration. In the latter case, females can postpone spawning for the duration of their recovery, and this can reduce their spawning. "
In short: donating a female horseshoe crabs can temper her love fervor, if not kill. (Only 18 percent of the horseshoe crabs observed by the author died.)
At the same time, the process of blood sampling is definitely better than the gross prey of the horseshoe crabs, which took place before, and science proves that there are no analogues of animal blood.
The logical question would be: why is the synthetic replacement for the amoebocyte lysate not yet invented? In the end, this is not the same as when we are still extracting diabetes insulin from pigs. We use yeast to make it, using a DNA sequence that encodes a protein.
That's what it turns out: companies are working on this solution. They would not want the extraction of their products to be regulated by the National Fisheries Plan , if they can avoid it.
In particular, biologist Ding Jack Ling from the National University of Singapore successfully developed a bacterial enzyme detector known as Factor C. He sold a production license to Lonza, which brought it to market as a product called PyroGene . The German company Hyglos is working on a new synthetic endotoxin detector . And other, even more advanced technological solutions are on the way.
So, good news for the horseshoe crabs! It’s like we discovered the oil field, and sperm whales started to celebrate it ( at least in the imagination of the cartoonist Vanity Fair ).
The cosmic-scale joke may be that the horseshoe crab, which for the last 30 years have been a significant part of the new biotechnological economy, will return their former fishing status to predatory snails. To represent a value in all cases is unprofitable for the horses. But to have no economic value in the end is the worst of all.
Horsetails are ancient animals with a history of more than half a billion years. They have unique habits and lifestyles while we observe them for decades. Their blue blood? This is due to the fact that copper in their blood plays the same role that iron plays in ours. Iron-based, oxygen-carrying hemoglobin molecules in our blood give a red color; copper-based, oxygen-carrying hemocyanin molecules in their blood make it blue.
Our own species appeared a thousand times later, having come to a real anatomical view a couple of hundred thousand years ago. Let's hope that we don’t destroy the horseshoe crabs after we finish cloning their ancient chemical wisdom.
Each year, up to half a million horseshoe crabs are trapped and bleeding to create a unique biomedical technology.
Frame from the PBS Nature documentary film - Two types of catastrophe
')
The first thought that comes about the blood of the horseshoe crab is blue, sky blue.
But the most remarkable feature of the blood of the horseshoe crabs is not the color. This is a chemical compound found only in amoebocytes of their blood cells, which is able to detect traces of bacteria and seize them in an irreversible thrombus.
To use this biological idiosyncrasy, pharmaceutical companies break down cells containing this substance, called a coagulogen. They can then use coagulogen as a contamination detector in any solution that may come in contact with blood. If dangerous endotoxins of bacteria are found in a liquid — even if their concentration is one part per trillion — the bloodtail's blood extract will set to work, turning the solution into what scientist Fred Bang, co-author of the discovery, called “gel.”
“It immobilizes bacteria but does not kill them.” - Bang wrote in 1956 in a work describing a substance. "The gel or clot was stable and sticky and remained so for several weeks at room temperature."
If there is no bacterial contamination, then coagulation does not occur, and a decision can be made that no bacteria are present. This is a simple, near-instant test called LAL , LAL , or Lime Amoebocyte Limulus. The test is named for the crab species, Limulus polyphemus.
The LAL test replaced a rather large number of horrific studies with all sorts of pollutants (large rabbit colonies) . Pharmaceutical companies do not like working with rabbits, among other things, because it is a slow and expensive process.
To date, testing with the help of the blood of a horseshoe crab has become a big business. “Every FDA-certified medical product (Food and Drug Administration, US Food and Drug Administration) must be tested with LAL.” The PBS Nature documentary says , “including surgical implants, such like pacemakers and prostheses. "
I don’t know how about you, but the thought that every person in America who has ever been injected was protected from bacteria because we collect the blood of invisible sea creatures with hidden chemical superpowers — I’m not a bit uncomfortable with this thought. This is not even from the script for the sci-fi film, it is postmodernism.
The only problem is that companies need large amounts of horseshoe crabs. Horseshoe whales inhabit the seabed, near the coastline. When they wish to mate, they swim in shallow water, and crabs catchers, standing at the bottom, snatch them from their native habitat.
Fishermen working for biomedical companies are not the first to come up with catching horseshoe crabs. Returning to the days of colonial America, "shell fertilizer" was used to enrich the fields. In the 20th century, even organized industry appeared in Delaver Bay. The shells of the horseshoe crabs evaporated and then were buried to feed the agricultural fields. Others went to feed for pigs. The number of crabs caught was estimated in the millions.
horseshoe crabs collection for fertilizer production, 1928. (Delaware State Archives)Due to the fact that we slowly destroyed the horseshoe crabs population, by the 1970s, the fertilizer industry from their shells had shrunk and disappeared. But the catch resumed in the 1990s, when the fishermen realized that they could use the horseshoe crab as bait for fishing. Including large mollusks, buccions and river eels.
In other words, these animals did not feel the friendliness of the people. They were not spoiled by the type of affection we endowed with, for example, tame rabbits. In the eyes of the people before the work of Fred Bang, the only virtue of the horseshoe crabs was their accessibility. They love the seashore, as we do.
And because of the high level of bacteria in this habitat, according to the assumption of Bang, the horseshoe crabs acquired their amazing chemical protection. Their circulatory system is more like a spider’s circulatory system than ours. If we inhale anything bad, this thing passes through our body and blood veins, having the unpleasant effects of communicating with white blood cells all the way. But if the bacteria make their way through the exoskeleton of the horseshoe crab, they can move freely causing harm.
“The presence of large sinuses allows blood to directly contact the tissues,” explains the history of the crab at the Woods Hole Oceanographic Institute. “There are a large number of large open cavities and bacteria, penetrating into the gaps in the shell of the horseshoe crab, easily enter the internal areas of the crab, presenting a potentially killer scenario.”
Coagulogen changes the admission mode in the bloodstream of the horseshoe crab. When crab blood cells feel invaded, they release granules with a chemical that becomes a sticky physical barrier to the movement of bacteria, preventing infection from spreading. The best metaphor would be the Ice Man's Super -Force from the X-Men movie , but instead of using cold to eliminate its enemies, the horseshoe crabs use their amazing chemical abilities.
These abilities, unfortunately, of the horseshoe crabs, are absent in humans.
After the crabs collectors deliver them to the laboratory, they pierce the tissue in the region of the hearts of animals and collect up to 30 percent of the animal's blood. Amoebocyte extract (LAL) is obtained from blood, its possible cost in the market reaches $ 15,000 per quart. Only five companies take blood from crabs: Associates of Cape Cod , Lonza , Wako Chemicals , Charles River Endosafe , and Limuli Labs (which do not have a website)
The horseshoe crabs are returned to the ocean far from the place where they were caught - to warn of the exsanguination of animals. The whole process takes from 24 to 72 hours.
Industry representatives report that a small number of animals are dying. However, about 10-30 percent of the total number of animals that bleed, actually die. This can be compared to how we donate blood. Crabs take apple juice, eat sweet cookies and soon return to normal.
But some experts point out problems. In areas where horseshoe crabs are harvested in large quantities for biomedical purposes, such as Pleasant Bay and Massachusetts, females spawn less and less. Perhaps the selection of blood, technically speaking, spoils them, if not even leads to death.
Researchers at the University of New Hampshire and Plymouth State University decided to test this hypothesis. They attached accelerometers to the horseshoe crab females, who shed blood for the good of our society.
horsetail equipped with an accelerometer
They described the results of a study in a new article in The Biological Bulletin, “The sublethal behavioral and psychological effects of the biomedical blood drawing process of the horseshoe crab, Limulus polyphemus.”
The process of blood sampling, as it turned out, makes bloodless animals more apathetic, slower and less willing to follow the tides, as is customary in their relatives.
“The changes that we observe in the degree of mobility, speed of movement, and exposure to tidal rhythms can have a detrimental effect on the daily activity of L. polyphemus, which is particularly associated with the roar throwing season,” they said. “Spawning necessitates several energy-intensive migrations to the tide strip, this is more true for females who can travel to the tide strip several times a week. A lack of activity, for example caused by blood sampling, can affect the number of such migrations or their duration. In the latter case, females can postpone spawning for the duration of their recovery, and this can reduce their spawning. "
In short: donating a female horseshoe crabs can temper her love fervor, if not kill. (Only 18 percent of the horseshoe crabs observed by the author died.)
At the same time, the process of blood sampling is definitely better than the gross prey of the horseshoe crabs, which took place before, and science proves that there are no analogues of animal blood.
The logical question would be: why is the synthetic replacement for the amoebocyte lysate not yet invented? In the end, this is not the same as when we are still extracting diabetes insulin from pigs. We use yeast to make it, using a DNA sequence that encodes a protein.
That's what it turns out: companies are working on this solution. They would not want the extraction of their products to be regulated by the National Fisheries Plan , if they can avoid it.
In particular, biologist Ding Jack Ling from the National University of Singapore successfully developed a bacterial enzyme detector known as Factor C. He sold a production license to Lonza, which brought it to market as a product called PyroGene . The German company Hyglos is working on a new synthetic endotoxin detector . And other, even more advanced technological solutions are on the way.
So, good news for the horseshoe crabs! It’s like we discovered the oil field, and sperm whales started to celebrate it ( at least in the imagination of the cartoonist Vanity Fair ).
The cosmic-scale joke may be that the horseshoe crab, which for the last 30 years have been a significant part of the new biotechnological economy, will return their former fishing status to predatory snails. To represent a value in all cases is unprofitable for the horses. But to have no economic value in the end is the worst of all.
Horsetails are ancient animals with a history of more than half a billion years. They have unique habits and lifestyles while we observe them for decades. Their blue blood? This is due to the fact that copper in their blood plays the same role that iron plays in ours. Iron-based, oxygen-carrying hemoglobin molecules in our blood give a red color; copper-based, oxygen-carrying hemocyanin molecules in their blood make it blue.
Our own species appeared a thousand times later, having come to a real anatomical view a couple of hundred thousand years ago. Let's hope that we don’t destroy the horseshoe crabs after we finish cloning their ancient chemical wisdom.
Source: https://habr.com/ru/post/401985/
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