Which cells does HIV infect?

[Immunobiology Research Institute, Siena]

This following was misleading regarding authorship. I quoted this material from David 
Perrit.  Please attribute it to the right guy/gal  ;-)
>
>Christopher Savoie (savoie at bioreg.kyushu-u.ac.jp) wrote:
>
>:*DAVID PERRIT* wrote:  
>: > There is no evidence that I know of showing direct CD8 infectivity.  
>: > CD4+8+ thymocytes can be infected but once they become single positive
>: > they are presumably resistant.

Sorry for the misquoting. (accidentally deleted the line) 

	I think an important point to remember is that, cell activation appears to be 
necessary for HIV-1 integration and viral replication. T cells which are positively 
selected in the thymus are presumably in the resting phase (though it was reported 
that mature T cells in thymus can have an activated phenotype prior to migration to 
the periphery - Bendelac, Nature 1991, 353:68). It is possible that CD4+8+ thymocytes 
which are infected with HIV does not favor viral replication. There is very good 
evidence that progress to single positive stage, i.e. down-modulation of either CD4 
or CD8 on double positive cells, is a random event (D. Littman - D. Mathias's groups, 
Cell-1993 April 23), which does not seem to require signalling via T cell receptor. 
So it could be possible that, CD4 is shut off in HIV infected CD4+8+ T cells  and if 
the CD8+ T cell is positively selected (assuming positive selection signals - 
whatever they are - have no influence on viral expression?) and remain resting for a 
while, HIV infection may eventually recede or enter latency. Actually, has anybody 
looked for frequency of CD8+ T cells with HIV proviral DNA? (I haven't yet read the 
refs posted by Chad Womack)

Derya



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Derya Unutmaz
Immunobiology Research Institute, Siena
Via Fiorentina 1,
53100, Siena, Italy.
E-mail: Unutmaz at iris02.biocine.it
Tel: +39-577-24 34 41
Fax: +39-577-24 35 64