Research for inhibitory mechanisms on eosinophil functions

Research Project

Project/Area Number	05454256
Research Category	Grant-in-Aid for General Scientific Research (B)
Allocation Type	Single-year Grants
Research Field	Respiratory organ internal medicine
Research Institution	The Department of Internal Medicine, Toho University, School of Medicine, Sakura Hospital
Principal Investigator	TOMIOKA Hisao Toho University, School of Medicine, Sakura Hospital, The Department of Internal Medicine, Professor, 医学部付属佐倉病院内科, 教授 (20009632)
Co-Investigator(Kenkyū-buntansha)	OCHIAI Ken-ichi Toho University, School of Medicine, Sakura Hospital, The Department of Internal, 医学部付属佐倉病院内科, 研究生 MATSUMURA Ryutaro Toho University, School of Medicine, Sakura Hospital, The Department of Internal, 医学部付属佐倉病院内科, 助手 (70246742) KAGAMI Masaru Toho University, School of Medicine, Sakura Hospital, The Department of Internal, 医学部付属佐倉病院内科, 助手 (50233656)
Project Period (FY)	1993 – 1995
Project Status	Completed (Fiscal Year 1995)
Budget Amount *help	¥6,200,000 (Direct Cost: ¥6,200,000) Fiscal Year 1995: ¥1,800,000 (Direct Cost: ¥1,800,000) Fiscal Year 1994: ¥1,800,000 (Direct Cost: ¥1,800,000) Fiscal Year 1993: ¥2,600,000 (Direct Cost: ¥2,600,000)
Keywords	Eosinophils / Cell differentiation / IL-4 / IL-5 / IFN-gamma / Apoptosis / Protooncogene / Antisense / BcI-2 / Fas抗原 / 高親和性IqE受容体 / Focal adhesion kinase / Bcl-2 / Fes抗原 / 高親和性lgE受容体 / 抗原提示 / サイトカイン
Research Abstract	1. In order to determine the regulatory mechanisms of eosinophil differentiation, we examined the effects of interleukin-4 (IL-4) and interferon-gamma (IFN-gamma) on the IL-3-and IL-5-induced eosinophils from cord blood mononuclear cells. (1) rhIL-4and rhlFN-gamma inhibited IL-3-and IL-5-induced eosinophil differentiation from umbilical cord blood mononuclear cells on day 28 of culture in a concentration-dependent manner, (2) The inhibitory effect of rhIL-4 and rhIFN-gamma was observed only when rhIL-4 or rhIFN-gamma was present in the culture from day 0 to day 14, (3) Addition of anti-rhIL-4 to the culture enhanced the IL-3-and IL-5-induced eosinophils differentiation. These results indicate that IL-4 and IFN-gamma have inhibitory effects on IL-3-and IL-5-induced eosinophils differentiation from its progenitor cells. 2. In order to determine regulatory mechanisms of eosinophil apoptosis, we examined the effect of IL-5 and IFN-gamma on eosinophil apoptosis and bcl-2 expression. (1) rhIL-5 (250pg/ml) significantly inhibited eosinophil apoptosis on 96 hr in vitro culture, (2) rhIL-5 significantly increased bcl-2 protein and mRNA expression on cultured eosinophils, (3) A phosphorothioate antisense oligonucleotide targeted the ATG translation initiation codon of bcl-2 (10-^5M) could significantly block the supportive effect of rhIL-5 (250pg/ml) for eosinophil survial compared with sense cDNA of bcl-2 on 96 hr culture, (4) On the contrary, rhIFN-gamma (1000U/ml) significantly inhibited eosinophils apoprosis on 96 hrin vitro culture but did not significantly upregulate bcl-2 protein. These results indicate that IL-5 have inhibitory effects on eosinophil apoptosis by regulation of bcl-2 expression.