Many people are in science fiction
cognition of the "blue blood" of aliens
1span 1 span1 1 _p
color is real life blood of which the most representative
called the
hòu horseshoe crab []
Horseshoe crab is an ancient creature
about 480 million years ago
has already lived on earth
about 200 million years before the first appearance of dinosaurs
_span3 still maintains its form span_span3 spanspan_span0 "Remains of the ocean"
is an animal that predates the dinosaurs.A veritable "living fossil"
crab tell you,
it really is not our crab family, close relatives oh !
because of its horseshoe crab carapace slightly horseshoe
and wearing longulus
and is often referred to Horseshoe Crab
Actually they do not belong to crustaceans
and they do not have tentacles like crabs or similar species on the head 3span _span _span _span 5 extinct trilobites
it might be related
four species of horseshoe crab existing global
America Limulus
(Limulus polyphemus) _span3s pan
is greenish brown to dark brown,Distributed on the Atlantic coast of America, from the coast of Maine in eastern North America to the Gulf of Mexico.
Chinese horseshoe crab
(Tachypleus tridentatus)
gray-green, located in Japan, South Korea, The coasts south of the Yangtze River in China (including the coasts of Zhejiang, Fujian, Guangdong, Hong Kong, Guangxi, and Hainan) are the coasts of Taiwan, Kinmen, Vietnam, the Philippines, Borneo, and Indonesia.
South Limulus
(Tachypleus gigas)
also known as giant horseshoe crab,Gray-green, distributed in Singapore, Borneo, Indonesia, Thailand, Malay Peninsula and Malay Islands along the coast of the Indian Bay of Bengal.
round tail limulus
(Carcinosvorpius rotundicauda)
to dark green-brown, located in From the coast of Southeast Asia to the Bay of Bengal, India, including Bangladesh, Thailand, Indonesia and Borneo.
likes to live in estuaries with lower salinity and has the habit of upstream.
scientific classification
| community | animal kingdom Animalia |
| door Arthropoda | Arthropoda |
| outline | merostomata Merostomata |
| mesh _ span3span | Xiphophorus mesh Xiphosura |
| suborder | Xiphophorus suborder Xiphosurida |
| infraorder | limulus infraorder Limulina |
| superfamily | horseshoe crab superfamily Limuloidea |
| Branch | Limulus Branch Limulidae |
What makes the number of horseshoe crabs so rare?
hordes of horseshoe crabs on the beach huge number of really
each time a female horseshoe crab 90,000 eggs were laid
, but only about 10 of them survived to adulthood
span spans, s, and paps, s, s, and s, s, spans, and s, s, spans, spans, and p Birds have eaten the eggs almost
Because of so many creatures
_ must feed on another level of limulus _span1 span1 _span5 span1 it
horseshoe crab can be considered as the ecosystem of the seas around the world
made a great contribution
another on the one hand It is the horseshoe crab containing
's special physical characteristics-
"blue blood" 47 strong 47
blood blue biological in nature earth has
Mollusca of squid , Arthropoda limulus
In the blood of horseshoe crab
oxygen-bound hemocyanin contains copper ions, so it presents blue-green _strong47 _strong47 _strong47 _strong47 _strong47 _strong47 _strong47 _strong47 _strong47 _p25p brp0
The reason why the blood of horseshoe crab is so precious
is because it has open-tube circulatory system
directly with cells blood Tissue contact
is more susceptible to infection by external bacteria
and limulus strong toxin-negative blood _span3 pspan1 span1 span1 strong _span3 pspan0 Extra sensitive
will quickly release a lectin when a bacterial invasion is detected strong
strong strong
The above phenomenon was first discovered and recorded in 1956 by a physician at Johns Hopkins University, Frederik Bang (Frederik Bang).
As the research continued to deepen, the blue blood reagent of Limulus Amebocyte Amebocyte Amebocyte Lysate (Limulus mulberry) was also used as an endotoxin detection reagent.
worth mentioning that
originally developed hemocyanin agent did not mature
70 years until the 20th century
U.S. Food and Drug Administration (FDA)
The test is mandatory for experimental drugs and surgical implants _span1 p5p 0 p5p 1 There is
. In the past forty years,
will have thousands or even millions of people,Died from unsanitary injections
According to the specifications of " Chinese Pharmacopoeia ", antibiotics, glucose, saline and vaccines used for injection must be tested for bacterial endotoxins before they are marketed.
and _span 3span _span reagent is widely used to detect the toxin in the blood of horseshoe crabs.
In the modern medical system, not only the new crown vaccine, but also every injection, every intravenous infusion, and every medical device that needs to be implanted into the human body. They are all inseparable from limulus.
horseshoe crab is in urgent need of protection, but horseshoe crab blood is a key raw material for an important reagent. The new crown vaccine has intensified demand, and alternatives are not yet mature.
There are currently 4 species of horseshoe crabs in the world.Two of them can be used in the production of limulus reagent.
①. Chinese horseshoe crab , LAL made its name
Tachypleus amebocyte lysate (TAL)
②. American horseshoe crab , the limulus reagent made by it is called
Limulus amebocyte lysate (LAL)
5p5br1p
The main reason.
Since limulus must return to the beach every year to lay eggs, and the disappearance and deterioration of the beach environment along the beach, the reproduction of limulus has been severely affected.
1span However, strong 44 The limulus reagent, which uses limulus blood as the raw material, is a necessary quality control reagent for many biomedical products, and its supply is directly related to the safety of drugs .
In 2021, the relevant policies to strengthen the protection of Chinese horseshoe crabs will be promulgated, and the real impact on the industry has attracted attention.
In fact, the limulus reagent is an extremely important part of the new crown vaccine production.
Kexing Biological said that its new crown inactivated vaccine does require limulus reagent for endotoxin testing. As for whether the limited raw materials of the limulus reagent will affect the production of the new crown vaccine, Kexing did not disclose. Sinopharm Zhongsheng did not respond to the inquiry of Caixin .
The gradual advancement of new crown vaccination will greatly boost global vaccine production. In 2018, the global vaccine production capacity was 3.5 billion doses, and according to Johns Hopkins University research analysis, at least 5 billion people need to be vaccinated to hope to achieve herd immunity. Based on this calculation,The global demand for the new crown vaccine may exceed 10 billion doses, more than three times the original production capacity.
The impact of the soaring demand for the new crown vaccine on Chinese horseshoe crab is difficult to estimate. According to related reports, domestic manufacturers often keep secrets about figures such as the number of horseshoe crabs captured and the amount of blood collected.
Limulus reagent is not without substitutes.
The recombinant factor C (rFC) method is currently the most promising method to replace the limulus reagent.
Naturally, factor C participates in the first step of the reaction between limulus blood and endotoxin, and it is activated by endotoxin to push the reaction to the next step.
and genetic engineering synthesis of recombinant factor C as a protein, after being activated by endotoxin, the fluorescent substrate emits light, which can be used for direct quantitative analysis of endotoxin.
Limulus reagent will undoubtedly remain the mainstream method of endotoxin detection in the short term.And rFC is currently mostly used in new products, rather than products already on the market.
To change the endotoxin detection method for products already on the market, there are steps required by regulations, and resources and manpower are required. Therefore, the market has a process of gradual adaptation and conversion to new alternative methods.
The most effective way to protect the population is _strongspan_strong44.
However, since juvenile horseshoe crabs are most suitable for growing in the intertidal muddy sandy beach areas, they are mostly released together with fish fry and shrimp fry in the offshore waters, and the effectiveness of release is difficult. Optimistic.
The implementation of various project measures means that human beings have been able to maintain the sustainable development of the limulus reagent supply in the limulus reagent industry. .
Crab Crab also sincerely hopes that the development of medical technology will realize the marketization of new technologies as soon as possible.Replace the blood of horseshoe crabs as a reagent, so as to better perform the sacred duty of protecting the safety of wildlife resources.
protection of human Limulus
2019 Nian 3 Yue -
horseshoe crab family "Chinese horseshoe crab"
was officially listed by IUCN as "endangered" (EN) 20
at a meeting held in Guangxi, China
World Conservation Union (IUCN) of (IUCN) _strong47 _strong47 _strong47 _strong _spanspan_strong47 _strong47
set this day of each year as "International Day of Horseshoe Crab Conservation"
hopes to draw people's attention to the fate of this species
p1span1 Span1 Span1 Span1 And standardize the use of wild limulus resources by the reagent industry
to reduce the damage and death of limulus during the blood collection process
strong 5 February 5 -
new " national key protected wild animal list "
officially announced
"Chinese horseshoe crab" and "Round-tailed scorpion horseshoe crab"
is officially listed as national second-level key protected wildlife
Limulus reagent manufacturers must apply for strong aquatic animal hunting license strong "
" aquatic wildlife management and utilization of licenses "
to the number approved by the competent authorities
limulus procurement of raw materials, the use of
Limulus reagent industry will also be further regulated
0span in the past,There are rumors that the food tonic effect of horseshoe crab is exaggerated, and it is deified in the folks as expensive nourishing ingredients with functions such as "promoting milk and promoting milk" and "clearing heat and detoxification".
Actually There is no investigation and research that shows that horseshoe crab has a tonic effect as a food material; moreover, it is harmful to the human body .
The hazards of eating "limulus"——
1. The meat contains allergies, which can cause allergies in meat.2. Their copper-rich blood may also cause heavy metal poisoning of . In addition, the common scorpion horseshoe crab in our country, there is also the tetrodotoxin-like which may be fatal.
Tips
Crab appeal to everyone -
cherish life,Refusal to eat wild protected animals
Review: Amy
p1span3 Span1 Span1 Span1 Span1 Span1 Network, if you infringe on your rights, please contact the editor in the background to delete the relevant infringing content. .-
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