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Staphylococcal enterotoxin B inhibits the production of interleukin‐4 in a human mast‐cell line HMC‐1
Author(s) -
Ackermann L.,
Pelkonen J.,
Harvima I. T.
Publication year - 1998
Publication title -
immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.297
H-Index - 133
eISSN - 1365-2567
pISSN - 0019-2805
DOI - 10.1046/j.1365-2567.1998.00508.x
Subject(s) - superantigen , enterotoxin , histamine , proinflammatory cytokine , biology , immunology , tumor necrosis factor alpha , cytokine , antigen , mast cell , microbiology and biotechnology , interleukin , monocyte , major histocompatibility complex , t cell , inflammation , immune system , pharmacology , biochemistry , escherichia coli , gene
Staphylococcal enterotoxins belong to the recently characterized group of immunocytotropic bacterial superantigens that are potent mitogens for human T cells. Superantigens are presented, but without intracellular processing, to T cells by monocyte/macrophages, Langerhans’ cells and keratinocytes via the class II major histocompatibility complex (MHC) molecules. Superantigens have been demonstrated to act as potent inducers of several proinflammatory cytokines in the antigen‐presenting cells such as interleukin‐1 (IL‐1) and tumour necrosis factor‐α (TNF‐α). As mast cells participate in the pathogenesis of several inflammatory skin disorders such as atopic dermatitis (AD), which is often aggravated by staphylococcal infections, we studied the effect of staphylococcal enterotoxin B (SEB) superantigen on the histamine release and IL‐4 expression in a human mast‐cell line (HMC‐1). Incubation of SEB (50 μg/ml) with HMC‐1 cells for 45 min, could not induce any histamine release. The HMC‐1 cells were also stimulated with various concentrations of SEB (0, 1, 10, 20, 50 μg/ml) for 1, 2, 3 and 4 days. Clear dose‐dependent inhibition of IL‐4 protein production and release was observed on day 4 without any observed effect on cell viability. Compared with unstimulated HMC‐1 cells, after 50 μg/ml SEB stimulation, the IL‐4 mRNA levels decreased steadily in the 2, 6, 18 and 24 hr samples in repeated experiments as measured with the reverse transcription–polymerase chain reaction (RT–PCR) method. In comparison, a biphasic decrease in TNF‐α expression was found. Our results show that in human leukaemic mast cells, superantigen stimulation downregulates the production of IL‐4. IL, interleukin
TNF‐α, tumour necrosis factor‐alpha
AD, atopic dermatitis
SEB, Staphylococcal enterotoxin B
Th, T helper
IFN‐γ, interferon‐γ
ICAM‐1, intercellular adhesion molecule‐1
RT–PCR, reverse transcription–PCR.