Lack of evidence for a superantigen in lymphocytes from HIV-discordant monozygotic twins.
OBJECTIVE
An HIV-associated superantigen (SAg) has been hypothesized. Here we test whether an SAg is functionally detectable in peripheral blood mononuclear cells (PBMC) from monozygotic twins discordant for HIV infection.


METHODS
The V beta selective T-cell depletion found in minor lymphocyte stimulation (Mls)-positive mice is caused by an SAg encoded by the mouse mammary tumour virus. Mls is a locus whose gene product stimulates a mixed lymphocyte reaction (MLR) in mice strains identical at the major histocompatibility complex locus. If an SAg is present in PBMC and/or sorted CD4+ cells from one HIV-infected monozygotic twin, it would stimulate PBMC from the corresponding healthy monozygotic twin in an MLR. In addition, if an SAg causes V beta-selective T-cell depletion in AIDS patients, a differential proliferation to a panel of staphylococcal enterotoxins (SE) of T lymphocytes from healthy and HIV-infected monozygotic twins should become measurable.


RESULTS
No positive MLR or significant differences in the SE-driven proliferation between the healthy and the HIV-infected twins were observed.


CONCLUSIONS
Our results suggest that PBMC from the two HIV-infected twins do not express a functionally detectable SAg.
Nisini
R
R
Dipartimento di Biopatologia Umana, Università La Sapienza di Roma, Italy.
Aiuti
A
A
Matricardi
P M
PM
Fattorossi
A
A
Ferlini
C
C
Biselli
R
R
Mezzaroma
I
I
Pinter
E
E
D'Amelio
R
R
D000328:Adult; D000818:Animals; D002478:Cells, Cultured; D004200:Diseases in Twins; D005260:Female; D006678:HIV / Q000276:immunology*; D015658:HIV Infections / Q000276:immunology*; D006801:Humans; D007959:Lymphocyte Culture Test, Mixed; D008214:Lymphocytes / Q000166:cytology / Q000276:immunology*; D008297:Male; D051379:Mice; D008875:Middle Aged; D018089:Superantigens / Q000276:immunology*; D014430:Twins, Monozygotic
D018089:Superantigens