Why do some animals, like sharks and crocodiles, have such powerful immune systems that they rarely get sick or develop cancer, and could we learn from them to improve human health?
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Along with the proteins in their immune system that quickly kill most infections, their wounds are also very quick to clot. Their clots are thick with a few layers of tissue, so bacteria don’t easily enter through their wounds.
Also, I saw this on a documentary a few years ago. Scientists discovered that an alligators’ immune system can kill HIV and they’re currently looking into incorporating the proteins from gator immune cells into HIV medicine for humans.
Bonus fact: They’re doing something similar with bee venom because a protein in their venom also kills the virus.
I believe that sharks “not getting cancer” is a myth. Sharks and other animals do get sick. Here is the difference, in nature you don’t last long when you are sick, you become food and disappear. So you have a selection bias here. Sick things disappear quick, so all you typically see are the sharks or animals that remained healthy. All that said some of these aquatic creatures do have ways to prevent cancer. In some cases it actually has to do with their genes. Some genes play a role in preventing cancer, and if I recall correctly, things like whales have more of them than people. So it isn’t the immune system so far as we can tell.
Welcome to the cancer paradox.
Each time a cell replicates it has a chance to make a mistake (or be affected by things like radition, etc.). Ligically a larger animal should be more likely to get cancer than small ones, since there‘s more cells that could potentially develop cancer. Yet we can see that mice are more likely to develop cancer than blue whales.
There are currently two quite plausibly theories:
– 1.: Hyper-tumors. In essence this theory says that large animals get cancer, which itself becomes so big that it develops cancer. This new tumor deprives the first tumor of it‘s nutrients, causing both to die.
– 2.: Large animals need massive tumors to kill. A small growth wouldn‘t cause enough damage to kill or seriously harm the host. Growing to a large enough size would take quite long, giving the host more time to fight off the cancer. Additionally it is also theprized that cancer can only grow to a certain size, after that it becomes too large to properly nourish itself. In other words, the host does get cancer but it cannot get big enough to be lethal
– 3.: Since large animals have a higher chance of developing cancer, they have evolved to be better at combating it. There are several mechanisms that an animal can use to defeat cancer. Small, short-lived animals haven‘t developed these as much as larger ones (according to the theory), since they don‘t get cancer enough to be relevant. Larger animals have these defense mechanisms better developed, as cancer would be a problem for them.
No theory is widely accepted to be the answer to this paradox. I personally believe in 2 and 3, but there‘s not enough evidence to clearly select one.
Along with the proteins in their immune system that quickly kill most infections, their wounds are also very quick to clot. Their clots are thick with a few layers of tissue, so bacteria don’t easily enter through their wounds.
Also, I saw this on a documentary a few years ago. Scientists discovered that an alligators’ immune system can kill HIV and they’re currently looking into incorporating the proteins from gator immune cells into HIV medicine for humans.
Bonus fact: They’re doing something similar with bee venom because a protein in their venom also kills the virus.
Along with the proteins in their immune system that quickly kill most infections, their wounds are also very quick to clot. Their clots are thick with a few layers of tissue, so bacteria don’t easily enter through their wounds.
Also, I saw this on a documentary a few years ago. Scientists discovered that an alligators’ immune system can kill HIV and they’re currently looking into incorporating the proteins from gator immune cells into HIV medicine for humans.
Bonus fact: They’re doing something similar with bee venom because a protein in their venom also kills the virus.
Welcome to the cancer paradox.
Each time a cell replicates it has a chance to make a mistake (or be affected by things like radition, etc.). Ligically a larger animal should be more likely to get cancer than small ones, since there‘s more cells that could potentially develop cancer. Yet we can see that mice are more likely to develop cancer than blue whales.
There are currently two quite plausibly theories:
– 1.: Hyper-tumors. In essence this theory says that large animals get cancer, which itself becomes so big that it develops cancer. This new tumor deprives the first tumor of it‘s nutrients, causing both to die.
– 2.: Large animals need massive tumors to kill. A small growth wouldn‘t cause enough damage to kill or seriously harm the host. Growing to a large enough size would take quite long, giving the host more time to fight off the cancer. Additionally it is also theprized that cancer can only grow to a certain size, after that it becomes too large to properly nourish itself. In other words, the host does get cancer but it cannot get big enough to be lethal
– 3.: Since large animals have a higher chance of developing cancer, they have evolved to be better at combating it. There are several mechanisms that an animal can use to defeat cancer. Small, short-lived animals haven‘t developed these as much as larger ones (according to the theory), since they don‘t get cancer enough to be relevant. Larger animals have these defense mechanisms better developed, as cancer would be a problem for them.
No theory is widely accepted to be the answer to this paradox. I personally believe in 2 and 3, but there‘s not enough evidence to clearly select one.
Welcome to the cancer paradox.
Each time a cell replicates it has a chance to make a mistake (or be affected by things like radition, etc.). Ligically a larger animal should be more likely to get cancer than small ones, since there‘s more cells that could potentially develop cancer. Yet we can see that mice are more likely to develop cancer than blue whales.
There are currently two quite plausibly theories:
– 1.: Hyper-tumors. In essence this theory says that large animals get cancer, which itself becomes so big that it develops cancer. This new tumor deprives the first tumor of it‘s nutrients, causing both to die.
– 2.: Large animals need massive tumors to kill. A small growth wouldn‘t cause enough damage to kill or seriously harm the host. Growing to a large enough size would take quite long, giving the host more time to fight off the cancer. Additionally it is also theprized that cancer can only grow to a certain size, after that it becomes too large to properly nourish itself. In other words, the host does get cancer but it cannot get big enough to be lethal
– 3.: Since large animals have a higher chance of developing cancer, they have evolved to be better at combating it. There are several mechanisms that an animal can use to defeat cancer. Small, short-lived animals haven‘t developed these as much as larger ones (according to the theory), since they don‘t get cancer enough to be relevant. Larger animals have these defense mechanisms better developed, as cancer would be a problem for them.
No theory is widely accepted to be the answer to this paradox. I personally believe in 2 and 3, but there‘s not enough evidence to clearly select one.
I believe that sharks “not getting cancer” is a myth. Sharks and other animals do get sick. Here is the difference, in nature you don’t last long when you are sick, you become food and disappear. So you have a selection bias here. Sick things disappear quick, so all you typically see are the sharks or animals that remained healthy. All that said some of these aquatic creatures do have ways to prevent cancer. In some cases it actually has to do with their genes. Some genes play a role in preventing cancer, and if I recall correctly, things like whales have more of them than people. So it isn’t the immune system so far as we can tell.
I believe that sharks “not getting cancer” is a myth. Sharks and other animals do get sick. Here is the difference, in nature you don’t last long when you are sick, you become food and disappear. So you have a selection bias here. Sick things disappear quick, so all you typically see are the sharks or animals that remained healthy. All that said some of these aquatic creatures do have ways to prevent cancer. In some cases it actually has to do with their genes. Some genes play a role in preventing cancer, and if I recall correctly, things like whales have more of them than people. So it isn’t the immune system so far as we can tell.
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