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Wednesday 28 March 2012

Cancer's Achilles Heel Identified?


There are the three kinds of immune cell that can kill cancerous cells: T cells, natural killer cells and macrophages. A few years ago the hot science news was that successful cancers were able to defend themselves against attack by these ferocious cells. It was not just a case of immune cells being too weak, or lacking observation skills - the cancer cells seemed to be influencing the actions of the immune cells.
Macrophages are the most likely kind of immune cell to detect and destroy a tiny cluster of cancer cells before things get out of hand. T and NK cells tend to circulate in the blood, rather than patrolling the tissues where cancers start. Macrophages are giant cells that travel around the body, engulfing and digesting anything that looks suspicious - bacteria, debris and body cells that don't feel right.
Scientists in the University of Stanford have now discovered one of the ways in which cancer cells protect themselves. They have "don't eat" me flags on them. These flags are messages directed at macrophages. What is more, they have successfully tested an antibody that can block this flag, allowing macrophages to identify and devour cancer cells.
The cancer cells in question were not just a single type but a highly diverse selection, originally human in origin, which were implanted in mice. The team must have been delighted to discover that the antibody disabled the flags on a very wide range of cancer cells leaving themselves vulnerable to murder by macrophage.
This opens up the exciting possibility of a new antibody-based treatment that could potentially treat a wide range of cancers. It could be the holy grail of cancer research, as the few existing new-wave treatments like Herceptin, are extremely specific and bring benefit only a small group of patients. Developing drugs like this, one at a time, is very slow and extremely expensive. This translates into a very high price tag for the drug when it is released. If this discovery could be turned into a new broad-spectrum cancer treatment for humans it could provide a much cheaper solution available to both rich and poor.


Sunday 25 March 2012

Mouse Immune System Responds to Music


It is not that surprising that music has been shown to reduce stress and distress in some human patients. But who would have thought that mice would be affected by music? But it seems that mice produce and respond to music. According to recent research, male domestic mice (and other species) sing, like songbirds, to attract a mate. Strange to think they might be warbling away beneath the floorboards. Fortunately their song is not audible to humans otherwise it might keep us awake.
Musical mice are also in the news due to recent Japanese research that involved playing opera and Enya to mice that were being subjected to heart transplants (Masateru Uchiyama et al, 2012).You would think the idea for this research might have been a bit of a wild card - but indeed someone's hunch paid off in terms of some interesting results. (But yes, this was tough on the mice and I don't think if I was on the ethics committee I'd have been talked into approving this one.)
Transplant survival increased in the mice that were treated to the non-stop opera (but not the new-age Enya) and there were significant changes in some key immune cells and molecules.
So should we conclude that music boosts your immune system? Not at all - increased transplant survival indicates less rejection - and therefore a less active immune response.
Does this research have an application in terms of human health and recovery? Again, I don't think so. The musical likes and dislikes of mice and humans might, after all, be different. Not to mention the musical preferences of their immune systems.
Should someone be trying to repeat this research on humans? Again the answer is no. You would have to persuade transplant patients to volunteer to put up with non-stop noise (classical, new-age, or just a high pitched sound) for a week before or after their operations. A bit of a non-starter I'd say. And humans are given anti-rejection drugs which would muddy the waters, to say the least. 
This is the kind of research that raises lots of questions, many of which may never be answered. But it does highlight that, even in mice, the interaction between the brain and the immune system is more complicated than we can begin to imagine.