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- Janefjord, Camilla, et al.
(författare)
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PHA-induced IL-12Rb2 mRNA expression in atopic and non-atopic children
- 2001
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Ingår i: Clinical and Experimental Allergy. - : Wiley. - 0954-7894. ; 31:10, s. 1493-1500
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Tidskriftsartikel (refereegranskat)abstract
- Background IL-12 is a strong inducer of Th1 responses. Stimulation via the CD2 receptor increases IFN-γ production and enhances the responsiveness of activated T-cells to IL-12, possibly due to an up-regulation of the signal transducing β2 chain of the IL-12 receptor (IL-12Rβ2). Atopic children have a reduced Th1-like immunity and a reduced CD2 expression. Our hypothesis is that atopic individuals have a reduced function of the CD2 pathway, causing reduced responsiveness to IL-12 and decreased IFN-γ production. Objective The aim was to study the mRNA expression of the IL-12Rβ2 chain, after stimulation via the CD2 pathway in peripheral blood mononuclear cells (PBMC), of atopic and non-atopic children, and to investigate correlations to the production of Th1 and Th2 cytokines. Materials and methods The study included 23 skin prick test positive, and 9 non-sensitized, 12-year-old children. PBMC were stimulated for 24 h with phytohemagglutinin (PHA) (2 µg/mL), which stimulates T cells through the CD2 pathway. Expression of IL-12Rβ2 mRNA was analysed by quantitative real time PCR and the cytokine production was detected with ELISA. Results Atopic and non-atopic children had similar baseline expression of IL-12Rβ2 mRNA, whereas PHA-induced IL-12Rβ2 mRNA expression was lower in atopic than in non-atopic children. The PHA-induced IL-12Rβ2 mRNA expression correlated well with the PHA-induced IFN-γ production and with the IFN-γ/IL-4 ratio. Conclusion PBMC from atopic children expressed less IL-12Rβ2 mRNA than non-atopic children after stimulation via the CD2 pathway (PHA). This may indicate a reduced capacity to respond to Th1-inducing stimuli in atopic children.
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| 3. |
- Zdolsek, Helena, et al.
(författare)
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Reduced IL-2-induced IL-12 responsiveness in atopic children
- 2003
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Ingår i: Pediatric Allergy and Immunology. - : Wiley. - 0905-6157 .- 1399-3038. ; 14:5, s. 351-357
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Tidskriftsartikel (refereegranskat)abstract
- Atopy may be associated with a reduced T-cell function particularly regarding maturation of T helper 1 (Th1) responses. We hypothesized that atopic children may have a reduced capacity to up-regulate the β2 subunit of the interleukin-12 (IL-12) receptor (IL-12Rβ2, the signal-transducing component). The study included 38 children followed from birth to the age of 7 years. Twenty one had a cumulative history of atopic disease, whereas 17 had none. Sixteen out of 21 children also had atopic symptoms within the past year (current), out of whom 10 children had atopic airway symptoms. The expression of IL-12Rβ2 mRNA was analyzed by quantitative real-time PCR and the secretion of interferon-γ (IFN-γ), IL-5 and IL-10 was assessed by enzyme-linked immunosorbent assay (ELISA). Children with current atopic airway symptoms and high levels of total IgE up-regulated IL-12Rβ2 mRNA expression less than non-atopic children with low IgE levels after IL-2 stimulation. This was accompanied by a low IL-2- and IL-12-induced IFN-γ production, possibly reflecting the reduced capacity of atopic children to up-regulate the IL-12 receptor. As IL-2 is needed to initiate and sustain immune responses and IL-12 promotes Th1 responses, this may contribute to the Th2-skewed pattern in atopic children.
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