Benefits of Vaccination

In the USA, the new rotavirus vaccine is protecting those who have had the vaccine - and many who have not been vaccinated. Rotavirus causes severe gastroenteritis and the vaccine was introduced for babies in the USA in 2006.

There has been dramatic reduction in hospital admissions for gastroenteritis in the age group that were vaccinated.

Groups that were too old to have been vaccinated - older children, adults and even elderly adults also showed a marked reduction in admissions for rotavirus.

This is a demonstration of "herd immunity" in action. The fewer people there are in the community who are susceptible to a virus, the less the virus gets passed around. And if you've ever had anything to do with a sick baby or child, you will know how good they are at sharing their infected body fluids with the whole family.

Rotavirus is a major killer of young children in poor countries, so if this vaccine could be used in such places it could have a significant impact.

It is licenced in the UK but is not on the NHS routine vaccination list. Maybe it should be.

http://www.sciencedaily.com/releases/2011/06/110624083550.htm

http://www.sciencedaily.com/releases/2011/08/110830082114.htm

Food poisoning

I am slowed down by a mild attack of food poisoning. Night before last, slowly mounting nausea drove me from bed to bathroom. Vomited just the once. It was a vivid reminder of the ferocity of gastric hydrochloric acid. I have no doubt it killed the bacteria - but the toxins they emitted are lingering on, along with the immune reaction they provoked. 

Had to struggle through the day yesterday and slept with deep unconsciousness from 8pm 'til 6.30. It's noon on day 2 now and my appetite is still poor and energy levels low. Those bacterial toxins have triggered a tidal wave of immune proteins that have found their way to my brain and are issuing orders. Rest! Eat lightly! Conserve your energy while we deal with the toxins in your body! I am hoping that my immune system will soon complete its job and allow me to return to normal. All I can do is wait.

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.

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.