Open AccessReduced interferon‐gamma (IFN‐γ) secretion with increased IFN‐γ mRNA expression in atopic dermatitis: evidence for a post‐transcriptional defect
Author(s) -
TANG M. L. K.,
VARIGOS G.,
KEMP A. S.
Publication year - 1994
Publication title -
clinical & experimental immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.329
H-Index - 135
eISSN - 1365-2249
pISSN - 0009-9104
DOI - 10.1111/j.1365-2249.1994.tb06114.x
Subject(s) - atopic dermatitis , immunology , interferon gamma , secretion , messenger rna , interferon , allergy , biology , gene expression , medicine , cytokine , gene , endocrinology , genetics
SUMMARY Reduced secretion of IFN‐γ in atopic individuals has been implicated in the pathogenesis of disease, though the mechanisms leading to this reduced secretion have not been elucidated. As production of IFN‐γ has been shown to be predominantly regulated by its rate of transcription, expression of IFN‐γ mRNA was examined in atopic children and in age‐matched, non‐atopic controls by polymerase chain reaction (PCR)‐assisted mRNA amplification. Children with atopic dermatitis were found to have constitutive expression of IFN‐γ mRNA in freshly isolated peripheral blood mononuclear cells (PBMC) and in unstimulated PBMC cultures which increased further following stimulation with phorbol myristate acetate (PMA)/Ca in vitro. In contrast, expression of IFN‐γ mRNA in controls was only detected in stimulated cultures, as has been demonstrated previously for normal adults. These findings demonstrate that circulating T cells from atopic children have been activated in vivo, and suggest that T cell activation is a significant component of the inflammatory process in atopic dermatitis. Although expression of IFN‐γ mRNA was increased in the atopic children, secretion was confirmed to be significantly lower than in controls, indicating that the defect(s) underlying reduced IFN‐γ secretion in these individuals lie post‐transcriptionally.