K R Pindolia, C J Noth, Y X Xu, N Janakiraman, R A Chapman, S C Gautam
{"title":"IL-4 upregulates IL-1-induced chemokine gene expression in bone marrow stromal cells by enhancing NF-kB activation.","authors":"K R Pindolia, C J Noth, Y X Xu, N Janakiraman, R A Chapman, S C Gautam","doi":"","DOIUrl":null,"url":null,"abstract":"<p><p>Bone marrow stromal cells play a critical role in the proliferation and differentiation of hematopoietic stem and progenitor cells by secreting numerous hematopoietic growth factors and colony-stimulating factors (CSFs). We have previously reported that monocyte chemotactic protein-1 (MCP-1 or MCP-1/JE) and interferon-inducible protein 10 KD (IP-10) are both induced in murine bone marrow stromal cell line +/(+)-1.LDA11 upon stimulation with various inflammatory agents, including IL-1 alpha, IFN-gamma, TNF-alpha, or LPS. In addition, the expression of MCP-1/JE and IP-10 mRNA by these inducers is potentiated by IL-4 and TGF-beta 1. In the present study we have investigated the mechanism of IL-4-mediated upregulation of MCP-1/JE gene expression. Our results of nuclear run-on experiments show that IL-4 enhances the IL-1-induced transcription of MCP-1/JE gene. Because the transcription of genes is regulated by DNA binding nuclear factors and binding sites for transcription factors AP-1 and SP-1, and NF-kB in the enhancer region of MCP-1/JE have been demonstrated, we examined the effect of IL-4 on the levels of these factors in stromal cells stimulated with IL-1. Whereas AP-1 and SP-1 are constitutively expressed in stromal cells, NF-kB is detected only after stimulation with IL-1. Furthermore, while unable to induce the activation of NF-kB alone, IL-4 enhanced the activation of NF-kB by IL-1. Taken together, these data suggest that upregulation of NF-kB may be the mechanism by which IL-4 increases the transcription of MCP-1/JE gene resulting in overabundance of the chemokine mRNA.</p>","PeriodicalId":79440,"journal":{"name":"Hematopathology and molecular hematology","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Hematopathology and molecular hematology","FirstCategoryId":"1085","ListUrlMain":"","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
Bone marrow stromal cells play a critical role in the proliferation and differentiation of hematopoietic stem and progenitor cells by secreting numerous hematopoietic growth factors and colony-stimulating factors (CSFs). We have previously reported that monocyte chemotactic protein-1 (MCP-1 or MCP-1/JE) and interferon-inducible protein 10 KD (IP-10) are both induced in murine bone marrow stromal cell line +/(+)-1.LDA11 upon stimulation with various inflammatory agents, including IL-1 alpha, IFN-gamma, TNF-alpha, or LPS. In addition, the expression of MCP-1/JE and IP-10 mRNA by these inducers is potentiated by IL-4 and TGF-beta 1. In the present study we have investigated the mechanism of IL-4-mediated upregulation of MCP-1/JE gene expression. Our results of nuclear run-on experiments show that IL-4 enhances the IL-1-induced transcription of MCP-1/JE gene. Because the transcription of genes is regulated by DNA binding nuclear factors and binding sites for transcription factors AP-1 and SP-1, and NF-kB in the enhancer region of MCP-1/JE have been demonstrated, we examined the effect of IL-4 on the levels of these factors in stromal cells stimulated with IL-1. Whereas AP-1 and SP-1 are constitutively expressed in stromal cells, NF-kB is detected only after stimulation with IL-1. Furthermore, while unable to induce the activation of NF-kB alone, IL-4 enhanced the activation of NF-kB by IL-1. Taken together, these data suggest that upregulation of NF-kB may be the mechanism by which IL-4 increases the transcription of MCP-1/JE gene resulting in overabundance of the chemokine mRNA.