Human lung mast cell activation leads to IL-13 mRNA expression and protein release.

Abstract

Using reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), we studied the generation of the recently described Th2 cytokine interleukin-13 (IL-13) by anti-IgE-activated lung fragments (LF), lung mast cells (LMC), and the mast cell line HMC-1. We found that IL-13 messenger ribonucleic acid (mRNA) was constitutively expressed in LF and rapidly increased after anti-IgE challenge, persisting throughout a 16-h period. Quantitative-competitive PCR (QCPCR) demonstrated an increase from 1.2 fg to 120 fg of IL-13 mRNA/micrograms LF total cellular RNA. Time-course experiments showed that IL-13 protein was not increased in supernatants at 2 h after activation, but was upregulated by 8 h. Anti-IgE-activated LF supernatants contained 592.1 +/- 314.8 pg IL-13/g wet weight of tissue at 24 h (mean +/- SE; n = 11). LMC demonstrated upregulation of IL-13 mRNA expression following treatment with A23187 (n = 4), with maximal upregulation by 3 h; anti-IgE or phorbol myristate acetate (PMA) also led to increased IL-13 mRNA expression. QCPCR analysis of LMC IL-13 mRNA expression at 4 h after activation showed a 7-, 13.8-, and 13.2-fold increase after A23187, anti-IgE, and PMA, respectively. Quantities of IL-13 released from optimally activated LMC and peripheral blood T cells were comparable. HMC-1 also showed enhanced IL-13 mRNA beginning 30 min after A23187 activation, with peak expression from 1 to 10 h, followed by waning over the subsequent 24 h. A23187 stimulation of HMC-1 led to 100-fold upregulation of IL-13 mRNA within 4 h and detectable IL-13 in 24-h supernatants. These results demonstrate that activation of LF and LMC through multiple signal-transduction pathways results in increased IL-13 mRNA and protein expression temporally consistent with a potential role in chronic allergic inflammation.

Production of IL-13 by human lung mast cells in response to Fcε receptor cross-linkage

“…The baseline level of IL-13 mRNA expression was relatively low, and was up-regulated within 2-4 h after activation of anti-IgE and SCF, persisted for up to 12 h and was almost undetectable by 24 h. Jaffe et al [15] previously reported that low basal levels of IL-13 mRNA were expressed by unstimulated human lung fragment and IL-13 mRNA expression was upregulated by 16 h following anti-IgE activatin. In their report, purified lung mast cells expressed IL-13 mRNA before stimulation and up-regulated for up to 3 h after stimulation by A23187.…”

“…Recent studies have revealed that the human mast cell line, HMC-1 [13] and human blood basophils [14] have the capacity to express and produce IL-13. Very recently, Jaffe et al have reported on IL-13 mRNA expression and IL-13 protein secretion following anti-IgE activation of human lung fragments and lung mast cells [15]. However, the time course of IL-13 gene expression and the exact amount of IL-13 production from highly purified human lung mast cells activated via the FceRI are not yet clear.…”

The Early Growth Response Factor-1 Is Involved in Stem Cell Factor (SCF)-induced Interleukin 13 Production by Mast Cells, but Is Dispensable for SCF-dependent Mast Cell Growth

“…Mast cells could serve as a potent source for IL-13 (11,48,49). During allergic inflammation, mast cells are likely produce mediators in the context of SCF and antigen co-stimulation.…”

Cord–Blood–Derived Human Cultured Mast Cells Produce Interleukin 13 in the Presence of Stem Cell Factor

“…Burd et al [8]have reported that the human mast cell line HMC–1, murine bone–marrow–derived cultured mast cells (BMCMC) and the murine mast cell line C1.MC/C57.1 produced IL–13, and Jaffe et al [9]reported that human lung mast cells produced IL–13. On the other hand, Yanagihara et al [10]failed to detect IL–13 production from the IgE and anti–IgE–stimulated human cultured mast cells, which have recently been established by Saito et al [11]as a useful model of human mast cells.…”