杏吧原创

A SWIG of beer could one day protect you from HIV, if a US company succeeds
in making an ultra-cheap vaccine out of brewer鈥檚 yeast.

Alex Franzusoff and his team at GlobeImmune of Denver have added an HIV gene
to yeast. When the modified yeast cells are injected into mice, they stimulate a
strong response from the immune system鈥檚 killer T cells. This is thought to be
crucial to create an effective vaccine. The team presented its findings at the
AIDS Vaccine 2001 conference in Philadelphia last week.

Because a yeast-based vaccine could be brewed up quickly and easily, it would
be very cheap. Just 100 litres could provide 5 million doses.

鈥淭his is definitely the main advantage,鈥� says Margaret Johnston, head of HIV
vaccine research at the US National Institute of Allergy and Infectious
Diseases. Other experimental HIV vaccines could cost thousands of dollars per
dose. Another bonus is yeast鈥檚 flexibility鈥攊t can incorporate vast amounts
of foreign DNA, so researchers could insert several HIV genes, which should make
any vaccine more effective.

But Johnston cautions that it鈥檚 easy to generate a strong T-cell response in
the mice GlobeImmune used. 鈥淚 would very much like to see the concept tested in
non-human primates before I got real enthused about it,鈥� she says.

So far, the yeast vaccine has been injected, but GlobeImmune is developing
intranasal and oral versions for a safety study in people. As well as
eliminating injections, Franzusoff sees another advantage: 鈥淎 beer version would
ensure full compliance from our volunteers.鈥�