DOUBLE STRANDED RNA INDUCED M2 RECEPTOR DYSFUNCTION

双链 RNA 诱导 M2 受体功能障碍

• 批准号: 6208192
• 负责人: WILLIAM M BOWERFIND
• 金额: $ 4.09万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-03 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6208192
• 关键词: bronchomotion; cytotoxic T lymphocyte; double stranded RNA; guinea pigs; helper T lymphocyte; interferon beta; interferon gamma; macrophage; monoclonal antibody; muscarinic receptor; neutralizing antibody; parasympathetic nervous system; receptor expression; tissue /cell culture

Acute viral infections increase airway responsiveness and increase vagally mediated reflex bronchoconstriction by decreasing the function and/or expression of inhibitory M2 muscarinic receptors on the parasympathetic nerves. In vitro studies suggest that interferon-gamma (IFNgamma) may be involved in this effect. Induction of interferon gene expression is a response of the cell to double stranded RNA (dsRNA) produced during replication of RNA viruses. Intraperitoneal (i.p.) injection of dsRNA causes airway hyperresponsiveness and loss of airway M2 muscarinic receptors. Our hypothesis is that interferon, expressed in response to double stranded RNA, is inhibiting M2 receptor gene expression in the lungs. The following specific aims are proposed: Specific aim number 1: To confirm the effects of i.p. dsRNA, and determine the role of IFN-gamma in these responses by pretreating animals with IFN-specific monoclonal antibodies. Circulating interferon will also be measured. Specific aim number 2: To determined the role of macrophages, and of CD4+ and CD8+ T-lymphocytes, in the response to dsRNA. Macrophages will be depleted using liposome-encapsulated clodronate, and CD4+ and CD8+ T- lymphocytes will be depleted using specific monoclonal antibodies, before dsRNA treatment, and the effects of these treatment on the subsequent response ro dsRNA will be determined. Specific aim number 3: To examine the effect of IFNbeta and dsRNA on M2 receptor gene expression and function in cultures of airway parasympathetic neurons.

急性病毒感染通过降低副交感神经上抑制性M2受体的功能和/或表达，增加呼吸道反应性和迷走神经介导的反射性支气管收缩。体外研究表明，干扰素-伽马可能参与了这一效应。干扰素基因表达的诱导是细胞对RNA病毒复制过程中产生的双链RNA(DsRNA)的反应。腹膜腔内(Ip)注射dsRNA可引起气道高反应性和M2受体的丢失。我们的假设是，干扰素是对双链RNA的反应而表达的，它抑制了肺部M2受体基因的表达。提出了以下具体目标：具体目标1：确认I.P.的效果。DsRNA，并通过用干扰素特异性单抗处理动物来确定干扰素-γ在这些反应中的作用。循环中的干扰素也将被测量。具体目标2：确定巨噬细胞以及CD4+和CD8+T淋巴细胞在dsRNA反应中的作用。在dsRNA治疗之前，巨噬细胞将使用脂质体包裹的氯屈膦酸盐被耗尽，而CD4+和CD8+T淋巴细胞将使用特定的单抗被耗尽，这些治疗对随后的dsRNA反应的影响将被确定。目的3：研究干扰素β和dsRNA对培养的呼吸道副交感神经细胞M2受体基因表达和功能的影响。