BACKGROUND: On activation by cross-linking the high-affinity IgE receptor (FcepsilonRI), expression of TNF-alpha, IL-3, IL-5, and IL-13 is induced in human intestinal mast cells. OBJECTIVE: We sought to examine, for the first time, FcepsilonRI signaling in mature human mast cells. METHODS: Mast cells were isolated from intestinal tissue and cultured in the presence of stem cell factor. The cells were treated with specific inhibitors before stimulation by means of FcepsilonRI cross-linking. Cytokine mRNA expression was analyzed by means of RT-PCR, and activation of signaling molecules was determined by means of immunocytochemistry, RT-PCR, Western blotting, and protein kinase C (PKC) assay. RESULTS: We found that nuclear factor-kappaB (NF-kappaB), as well as c-Fos and c-Jun, the components of activator protein 1 (AP-1), are activated after FcepsilonRI cross-linking in human intestinal mast cells. Treatment of the cells with specific inhibitors revealed an involvement of NF-kappaB and nuclear factor of activated T cells, as well as the necessity of extracellular signal-regulated kinase 1/2 (ERK-1/2), PKC, and AP-1 for the induced cytokine gene expression. Consistently, we found that activation of c-Fos corresponds with the induced cytokine gene expression and that ERK-1/2, an activator of c-Fos, was activated in response to FcepsilonRI cross-linking. CONCLUSION: Our data on human mast cells show that the activity of ERK-1/2, PKC, and subsequent activation of AP-1 are necessary for the FcepsilonRI-mediated cytokine expression. Nuclear factor of activated T cells and NF-kappaB seem to be necessary for the induction of TNF-alpha, IL-3, and IL-13 but are less important for the transcription of IL-5.
BACKGROUND: On activation by cross-linking the high-affinity IgE receptor (FcepsilonRI), expression of TNF-alpha, IL-3, IL-5, and IL-13 is induced in human intestinal mast cells. OBJECTIVE: We sought to examine, for the first time, FcepsilonRI signaling in mature human mast cells. METHODS: Mast cells were isolated from intestinal tissue and cultured in the presence of stem cell factor. The cells were treated with specific inhibitors before stimulation by means of FcepsilonRI cross-linking. Cytokine mRNA expression was analyzed by means of RT-PCR, and activation of signaling molecules was determined by means of immunocytochemistry, RT-PCR, Western blotting, and protein kinase C (PKC) assay. RESULTS: We found that nuclear factor-kappaB (NF-kappaB), as well as c-Fos and c-Jun, the components of activator protein 1 (AP-1), are activated after FcepsilonRI cross-linking in human intestinal mast cells. Treatment of the cells with specific inhibitors revealed an involvement of NF-kappaB and nuclear factor of activated T cells, as well as the necessity of extracellular signal-regulated kinase 1/2 (ERK-1/2), PKC, and AP-1 for the induced cytokine gene expression. Consistently, we found that activation of c-Fos corresponds with the induced cytokine gene expression and that ERK-1/2, an activator of c-Fos, was activated in response to FcepsilonRI cross-linking. CONCLUSION: Our data on human mast cells show that the activity of ERK-1/2, PKC, and subsequent activation of AP-1 are necessary for the FcepsilonRI-mediated cytokine expression. Nuclear factor of activated T cells and NF-kappaB seem to be necessary for the induction of TNF-alpha, IL-3, and IL-13 but are less important for the transcription of IL-5.
Authors: Neerad C Mishra; Jules Rir-sima-ah; R Thomas Boyd; Shashi P Singh; Sravanthi Gundavarapu; Raymond J Langley; Seddigheh Razani-Boroujerdi; Mohan L Sopori Journal: J Immunol Date: 2010-05-26 Impact factor: 5.422
Authors: Jamie Josephine Avila McLeod; Heather L Caslin; Andrew J Spence; Elizabeth M Kolawole; Amina Abdul Qayum; Anuya Paranjape; Marcela Taruselli; Tamara T Haque; Kasalina N Kiwanuka; Howard L Elford; John J Ryan Journal: Cell Immunol Date: 2017-09-21 Impact factor: 4.868