Comparison of interferon-gamma and interleukin-4 production by peripheral blood mononuclear cells and isolated T cells after activation with polyclonal T cell activators.
Controversial data have been reported regarding the ability of peripheral blood T cells to secrete interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) from atopic patients as compared to nonatopic healthy controls. In most of these studies, T cells in peripheral blood mononuclear cell preparations (PBMC) were stimulated with polyclonal T cell activators. Some of these activators are able to activate cells other than T cells in the PBMC preparations which may influence the lymphokine levels in supernatants of PBMC. To evaluate this, we compared the IFN-gamma and IL-4 levels in PBMC and isolated T cell preparations after activation with phytohemagglutinin (PHA), Concanavalin A (ConA), anti-CD3 plus phorbol myristate acetate (PMA), or ionomycin plus PMA. The IFN-gamma and IL-4 levels in the supernatants were calculated based on the percent T cells in the preparations. Whereas all activators induced significant IFN-gamma secretion, only ionomycin plus PMA stimulation induced large IL-4 secretion. In virtually all cases, the IFN-gamma levels calculated on a per T cell basis differed for PBMC versus isolated T cells. Whereas in some donors the IFN-gamma levels were higher in PBMC preparations than in T cells, in others it was the opposite. Similarly, in about one half of both normal and atopic donors tested, the IL-4 levels of activated PBMC were 2- to 7-fold lower than levels in isolated T cells. The data suggest that non-T cells have a significant effect on the IFN-gamma and IL-4 levels in supernatants of polyclonally activated PBMC.(ABSTRACT TRUNCATED AT 250 WORDS)
Gonzalez
S
S
University of California, San Diego School of Medicine, Department of Pediatrics, La Jolla 92093-0609.
Beck
L
L
Wilson
N
N
Spiegelberg
H L
HL
D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis*; D015847:Interleukin-4 / Q000096:biosynthesis*; D015759:Ionomycin / Q000494:pharmacology; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D008213:Lymphocyte Activation; D008222:Lymphokines / Q000378:metabolism; D013601:T-Lymphocytes / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D008222:Lymphokines; D015847:Interleukin-4; D015759:Ionomycin; D007371:Interferon-gamma; D013755:Tetradecanoylphorbol Acetate