6 | NewScientist | 21 November 2009

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HIV vaccines based on the cold virus could make people “sitting ducks” for HIV infection.

A study led by Steven Patterson of Imperial College London revives an earlier theory that adenoviruses cause an immune “own goal” by priming people’s immune systems to produce CD4 cells, the cells HIV prefers to infect. Since the viruses are also used in vaccines against malaria and tuberculosis, the finding could be a major blow .

The problems were first raised in 2007, when the trial of an HIV vaccine that used an adenovirus was stopped after more subjects than expected became infected with HIV. At the time it was

suggested that recipients who had previously been exposed to the adenovirus had a heightened susceptibility to HIV infection, but two studies published in July

HIV vaccine fears contradicted that ( New Scientist, 25 July, p 14) .

In the latest twist, Patterson’s team took CD4 cells from 20 healthy volunteers and exposed them to adenoviruses. They found that CD4 cells from people who had previously been exposed to the viruses increased by up to 8 per cent, while cells from those who hadn’t been exposed did not multiply. This suggests that re-exposure makes people more vulnerable to HIV infection, the team say (Proceedings of the

National Academy of Sciences, DOI: 10.1073/pnas.0907898106).

Water, water…

EVERYWHERE? Not quite, but NASA’s LCROSS mission did kick up a few bucketfuls after all when it collided with the moon.

On 9 October, the LCROSS team smashed a spent rocket stage into the moon. The idea was to kick up a plume of material that could be analysed for water.

Earth-based observers had trouble seeing the ejecta, partly because it was hidden by a ridge . The shepherding spacecraft told a different story: it followed the rocket stage on its collision

course, and on the way measured more than 100 kilograms of water ice in the part of the plume it observed. “We didn’t find just a little bit. We found a significant amount,” says LCROSS principal investigator Anthony Colaprete of NASA’s Ames Research Center in Moffett Field, California.

This confirms that the moon’s poles contain stores of water ice – more than the traces found by India’s Chandrayaan-1 probe in September. “LCROSS has now made that definitive discovery, says Greg Delory of the University of California, Berkeley.

Taser beats baton

USING a Taser to subdue a suspect is safer than police batons and fists. That is the unexpected conclusion of a study of incidents in which US police used force to tackle a person who was resisting arrest.

Several people have died in the US after being tasered, and human rights groups have spoken out against the weapons. But John MacDonald of the University of Pennsylvania in

–Messages from Singapore–

–Weapon of choice?–

Don’t expect the earth…IT’S official: the organisers of the

Copenhagen climate conference

conceded last weekend that it cannot

deliver a final, legally binding deal.

Danish prime minister Lars Løkke

Rasmussen, the conference host, is

hoping for a “political deal”, followed by

a legal one in 2010. The question now

is how specific the political deal will be.

Speaking at a meeting of Asian

leaders in Singapore, Rasmussen said

the Copenhagen agreement should be

“precise on specific commitments and

binding on countries committing to

reach certain targets. We need the

commitments. We need the figures. We

need the action.” His climate minister,

Connie Hedegaard, says it is “most

important that the US commit to bring

specific numbers to Copenhagen”.

Will it? That’s in the balance. Though

keen to agree a climate treaty,

President Barack Obama is thought

to be reluctant to make promises

Congress will not let him keep – as

Al Gore did in Kyoto in 1997 when he

was vice-president. Obama wants the

climate change bills before Congress

to pass before making firm pledges.

This won’t happen before Copenhagen.

If or when they do pass, much

could change. In Singapore, President

Hu Jintao of China again insisted

that his country will not commit to

reducing its carbon intensity unless

the US is fully committed to cutting

emissions. Optimists say that if Obama

can get a bill through Congress, an

international deal that now looks

impossible will be eminently doable

next year. For the pessimists, climate

talks just ran into the sand.

“Vaccines containing cold viruses prime the immune system to produce cells HIV prefers to infect”

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