In article <363a051e.329875203 at netnews.worldnet.att.net>,
johnburgin at worldnet.att.net wrote:
> Then what's the big hold up on a vaccine?
Several. For starters:
1) we don't know what in the case of HIV-1 protective immunity looks like.
For almost every viral infection there is a percentage of infected
individuals that clear the virus from their system through an effective
immune response. Mimicking that response is a good start towards a
vaccine. Such immunity has not been demonstrated for HIV-1
2) lack of a good animal model in which vaccine regimens can be rapidly
tested. SIV infection of macaques comes close and is the most widely used
system. Mostly this system has now demonstrated what doesn't work, but
some good leads have also been obtained
3) rapid mutation of the viral entity, making it hard to know what to
protect from
4) (supposed) need for both humoral and cellular immunity against multiple
epitopes
Marnix Bosch
