title: IgE in the absence of allergen induces the expression of monocyte chemoattractant protein-1 in the rat basophilic cell-line RBL-2H3.
abstract: Recently, basophils have been suggested to produce inflammatory mediators in response to IgE in the absence of allergens. Monocyte chemoattractant protein-1 (MCP-1) plays an important role in the initiation of inflammatory responses by recruiting various immune cells to the site of allergic inflammation. In the present study, we examined whether IgE under allergen-free conditions could stimulate basophils and lead to the production of MCP-1. Exposure of the rat basophilic cell-line RBL-2H3 to IgE without allergen resulted in a dose- and time-dependent induction of MCP-1 expression at both the mRNA and protein level. Although allergen was not necessary for IgE-induced MCP-1 expression, it was essential for degranulation as determined by β-hexosaminidase release assay. IgE enhanced phosphorylation of MAP kinases including ERK, p38 kinase, and JNK. However, IgE-induced MCP-1 expression was attenuated by inhibitors for JNK and PKC. Concomitantly, IgE induced activation of AP-1, which is an important transcription factor for MCP-1 gene expression in RBL-2H3 cells. Taken together, our results suggest that IgE alone is sufficient to stimulate basophils to increase expression of MCP-1, which in turn might contribute to the inflammatory response.
authors: Department of Oral Microbiology and Immunology, DRI, and BK21 Plus Program, School of Dentistry, Seoul National University, 28 Yongon-Dong, Chongno-Gu, Seoul 110-749, Republic of Korea.
authors: Ki Bum
authors: KB
authors: Ahn
authors: Division of High-risk Pathogen Research, Center for Infectious Diseases, Korean National Institute of Health, Cheongwon-gun, Chungbuk 363-951, Republic of Korea.
authors: Jun Ho
authors: JH
authors: Jeon
authors: Department of Oral Microbiology and Immunology, DRI, and BK21 Plus Program, School of Dentistry, Seoul National University, 28 Yongon-Dong, Chongno-Gu, Seoul 110-749, Republic of Korea.
authors: Seok-Seong
authors: SS
authors: Kang
authors: School of Biotechnology and Institute of Life Science and Resources, Kyung Hee University, Yongin 446-701, Republic of Korea.
authors: Dae Kyun
authors: DK
authors: Chung
authors: Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea.
authors: Cheol-Heui
authors: CH
authors: Yun
authors: Department of Oral Microbiology and Immunology, DRI, and BK21 Plus Program, School of Dentistry, Seoul National University, 28 Yongon-Dong, Chongno-Gu, Seoul 110-749, Republic of Korea. Electronic address: shhan-mi@snu.ac.kr.
authors: Seung Hyun
authors: SH
authors: Han
mesh_terms: D000485:Allergens / Q000276:immunology; D000818:Animals; D001491:Basophils / Q000187:drug effects / Q000276:immunology*; D002460:Cell Line; D018932:Chemokine CCL2 / Q000235:genetics / Q000276:immunology*; D015870:Gene Expression / Q000187:drug effects; D007073:Immunoglobulin E / Q000276:immunology*; D007249:Inflammation / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000187:drug effects; D011493:Protein Kinase C / Q000502:physiology; D051381:Rats; D018808:Transcription Factor AP-1 / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics
chemical_list: D000485:Allergens; C491766:Ccl2 protein, rat; D018932:Chemokine CCL2; D018808:Transcription Factor AP-1; D007073:Immunoglobulin E; D011493:Protein Kinase C
keywords: Basophils; Immunoglobulin E; Monocyte chemoattractant protein-1