Friends, we have all received intravenous injections. Some have received artificial organs. In all these cases something from outside the body is put within the body.
Things outside the body can be pretty dangerous. Viruses and Bacteria are everywhere. It can be very dangerous if a bacteria enters the blood stream through a contaminated injection! The sick person has a weak immune system and even a simple bacteria in the bloodstream can be fatal.
How do we make sure that the injections are free of these harmful germs?
One way is to steam sterlize them. But there are some bacteria called the “Gram-negative” bacteria that survive steam sterlization! How do we know that the injection is not contaminated?!
One way to test the purity of a drug was to inject it to a rabbit.
If it lives the drug is pure. If it dies then the drug is contaminated by bacteria. And this technique was used till 1960s!!!
In 1960s a substance was discovered which would help us detect efficiently any pathogens in a substance. It was a chemical obtained from the blood of a horseshoe crab. This chemical is known as Limulus Ameobocyte Lysate(LAL). This chemical is ONLY found in the blood of one creature- the horseshoe crab. Scientists have not been able to make it artificially in a lab- the only way to get it is to get it from Horseshoe crab’s blood.
LAL is a remarkable substance. If it touches any bacteria it immediately clots. So to check if any substance has any bacteria in it just put a few drops of LAL in that substance. If the LAL clots then the substance is contaminated with bacteria. If LAL does not clot then the substance is pure. This technique is so effective that every drug that can be injected and every artificial organ has to be tested with LAL before it can be released in the market.
So the horseshoe crab’s blood has saved millions of lives from dangerous bacteria. Lets study the horseshoe crab and its blood in some more detail.
The horseshoe crab is not a crab. It is not anything we know. It is an ancient creature that has somehow survived to the present times. It is a creature that first appeared on earth 120 to 200 million years ago.
So it is from the early dinosaur era. Its body and biology have not changed in the last 120 million years. It is a “living fossil”.
Our blood is red because it contains hemoglobin. The horseshoe crab contains no hemoglobin. It contains copper and is therefore blue in colour.
Most animals(including humans) have a very advanced immune system- if bacteria/virus enter the body antibodies are produced in the blood which kill these invading microbes. This kind of an immune system is a newer development. Remember that the horseshoe crab has not changed for more than 120 million years. So the horseshoe crab does not have a modern immune system. It has a very basic and simple immune system – if a bacteria/virus is found in the blood the blood will clot around it. So the clots around the invading bacteria makes them immobile and unable to reproduce. It might be a simple immune system but is has helped the horseshoe crab survive 200 million years! And it is this clotting property of the immune system that helps modern medicine detect bacterial contamination in injectible medicines.
The Horseshoe crab is very very important creature for our health. We need to preserve it and make sure it does not become extinct. To get LAL horshoe crabs are not killed. They are caught, bled and left back in the sea alive.
Friends, human imagination is very limited. Nature and her imagination is infinite. We pride ourselves in creating clever tools and gadgets but compared to nature’s creations these are nothing. Technology is not a pure creation of the human brain. Most technologies just try to mimic nature. It is Science that is a true nature lover’s domain. The cure to ills like AIDS and cancer will not be invented in the labs of the medical technologist. These cures will be discovered in the sap, blood, veins, organs of plants and animals in the dense forests of Amazon and the depths of the Pacific. We can not create even a substance that detects bacteria- how can we be proud of our technology? To save our own lives from the diseases of injected bacteria we need the blood of a 200 million years old creature- the horseshoe crab.
We must preserve nature, we must study nature, we must respect nature, we must worship nature.
Go, wondrous creature! mount where Science guides:
Go, measure earth, weigh air, and state the tides:
Instruct the planets in what orbs to run,
Correct old time and regulate the Sun;