Wednesday, 7 July 2010
Are humans bigger mice without tails?
I have been sighing a lot over my laptop lately as a plethora of research these days claims that scientists could soon protect the whole of human kind from this disease or that disease.....on the basis of experimentation on mice.
One example is this reported in ScienceDaily which states: "The immune system of mice is very similar to that of humans".
I'm sorry but I cannot accept this bland statement. So often when I check the research papers, the researchers refer to the adaptive immune system (the one that recognises particular pathogens and then attacks) as if this is the only one there is.
In addition to the skin, the other layer of protection for the body is the innate immune system. This offers a constant and universal defence against dangers presented by microbes in the body. It is permanently on stand-by and can react to anything within seconds, sending a change along hundreds of response pathways.
The innate system consists of a variety of relatively little-researched receptors embedded in to the cells of our body. Some of these are called Toll-like receptors (TLR).
It is now known that humans - but not mice - have TLR10, plus mice have the additional TLRs 11, 12 & 13. Also the working of TLR8 is different in humans, compared with mice.
I wish scientists would stop publishing papers that raise false hopes when clearly there is a big difference between the two mammals.
We may need increased research on fruit flies, not mammals, in my opinion. Yes! According to NASA scientists "Genetically speaking, people and fruit flies are surprisingly alike. About 61% of known human disease genes have a recognizable match in the genetic code of fruit flies, and 50% of fly protein sequences have mammalian analogues."
And they seem perfect for researching the little-known innate immunity pathways since fruit flies have no adaptive immune system.
Knowing these facts, I wonder if I could evolve a tail in the time that current pharmaceutical-based research can come up with human disease cures based on mouse models. Sorry to sound pessimistic, but I wish research money was directed in to more helpful avenues.