antigen presentation and enhancing antibody

[David Beasley]

In article <478ad1$bnj at panix.com>, iayork at panix.com (Ian A. York) says:

[SNIP]

>As far as antibody-mediated enhancement of infection, it's only seen in a
>relative handful of viruses, of HIV may (or may not, in vivo) be one.  The
>classic example is dengue virus.  The two basic requirements (fairly
>obvious, really) are that the antibodies be non-neutralizing and the virus
>be able to survive in an Fc-bearing cell.  Here are a couple of papers you
>might find useful -
>
> Kurane I.  Rothman AL.  Livingston PG.  Green S.  Gagnon SJ.  Janus J. 
>Innis BL.  Nimmannitya S.  Nisalak A.  Ennis FA. 
> Immunopathologic mechanisms of dengue hemorrhagic fever and dengue shock
>syndrome. 
> Archives of Virology - Supplementum.  9:59-64, 1994.
>
> Jiang SB.  Lin K.  Neurath AR.
> Enhancement of human immunodeficiency virus type 1 infection by 
>antisera to peptides from the envelope glycoproteins gp120/gp41
>Journal of Experimental Medicine.  174(6):1557-63, 1991
>
[SNIP]

Some neutralising antibodies have been shown to enhance in vitro dengue
virus infection of cells when present at low concentrations.  

As far as I know, antibody-dependent enhancement of dengue infection has
still only be demonstrated as an in vitro phenomenon.  ADE is a nice
theory for the development of dengue haemorrhagic fever, but still doesn't
explain why only 2-3% of anamnestic infections result in the more severe
form of disease.  The whole concept of ADE seems to be fairly contentious
amongst flavivirus (and particularly dengue) researchers.

David B.


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David Beasley                              
School of Life Science                      
Queensland University of Technology        
GPO Box 2434                                 
BRISBANE, QUEENSLAND, AUSTRALIA, 4001
Email: d.beasley at qut.edu.au
WWW:  http://www.life.sci.qut.edu.au/david/index.htm
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