Plasma antiviral activity and interferon-gamma production by superantigen-stimulated lymphocytes during normal human pregnancy.
OBJECTIVE
Plasma interferon (IFN)-beta levels, lymphocyte responsiveness, and evaluation of the relationship between circulating antiviral activity (AA) and IFN-gamma production were studied in pregnant women and nonpregnant age-matched controls with the objective of elucidating the downregulation of IFN-gamma production in successful pregnancy.


METHODS
In plasma and supernatants of peripheral blood mononuclear cell (PBMC) cultures, stimulated with staphylococcal enterotoxin A (SEA) superantigen, from 43 pregnant women with a history of normal pregnancy and 30 healthy nonpregnant age-matched controls, levels of AA were measured in a micromethod by inhibition of the cytopathic effect (CPE) caused by vesicular stomatitis virus (VSV) in the human amnionic cell line (WISH).


RESULTS
Significantly higher plasma AA (60% was IFN-gamma and residual activity was acid-labile IFN-like) was present in pregnant women than controls. On the other hand, SEA-activated PBMCs from pregnant women produced significantly lower IFN-gamma levels than those of nonpregnant women. Furthermore, maternal plasma AA levels correlated negatively with IFN-gamma production by SEA-stimulated PBMCs.


CONCLUSIONS
The hypothesis that successful pregnancy requires downregulation of IFN-gamma is only partially sustained, suggesting that the immunology of pregnancy is more complex and that murine and human pregnancy have different cytokine profiles.
Grasso
G
G
Department of Biomedical Science, University of Siena, Italy. grasso@unisi.it
Massai
L
L
Migliaccio
P
P
Picciolini
E
E
Muscettola
M
M
D000328:Adult; D000998:Antiviral Agents / Q000097:blood*; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000097:blood*; D008213:Lymphocyte Activation / Q000276:immunology*; D011247:Pregnancy / Q000276:immunology*; D011256:Pregnancy Outcome; D011264:Pregnancy Trimesters / Q000276:immunology; D018089:Superantigens / Q000276:immunology
D000998:Antiviral Agents; D018089:Superantigens; D007371:Interferon-gamma