REGULATION OF IMMUNE RESPONSES IN HUMANS AND NON-HUMAN PRIMATES

人类和非人类灵长类动物免疫反应的调节

• 批准号: 3768794
• 负责人: W STROBER
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3768794
• 关键词: B lymphocyte; Primates; cytokine; gene rearrangement; human subject; immunoglobulin G; immunoglobulin genes; immunoregulation; leukocyte activation /transformation; lymphocyte proliferation; messenger RNA; polymerase chain reaction; tumor necrosis factor alpha

I) To further elucidate B cell isotype differentiation in humans we defined the conditions necessary for IgG sub-class-specific germline transcript (GLT) production in human peripheral blood cells. We found that induction of GLT for the various IgG subclasses fell into two patterns. Induction of Cgamma3 and Cgamma1, GLT, transcripts of genes in the first human duplication unit, generally required a proliferative stimulus (SAC) and was brought about by SAC plus IL-4 (Cgamma3 GLT) and SAC alone or SAC plus IL-2 (Cgamma1 GLT); in contrast, induction of Cgamma2 and Cgamma4 GLT, transcripts of genes in the second duplication unit, was induced accomplished with cytokines alone: IFN-gamma (Cgamma2 GLT) and IL-4 (Cgamma4 GLT), and was not augmented by addition of a proliferative stimulus. Finally, we found that IFN-gamma inhibited IL-4- induced Cgamma3 and Cgamma4 GLT (with or without SAC). These findings establish that the various human IgG subclasses manifest distinct requirements for the regulation of early steps in isotype differentiation. In addition, they suggest that human Cgamma genes exhibit patterns of regulation related to their respective gene duplication units. II) IL-10 has recently been shown to have an important influence on human B cell differentiation. To learn about the regulation of this cytokine we tested the hypothesis that its production by monocytes is under control of one of the inflammatory cytokines. In initial studies, we co-cultured purified human peripheral blood monocytes with a panel of cytokines including TNF-alpha, IL-1alpha, IL1-beta, IL-6, GM-CSF, TGF- beta and IFN-alpha, and then measured IL-10 mRNA production using a semi- quantitive reverse transcription-polymerase chain reaction (RT-PCR) technique. We found that TNF-alpha has a major effect on IL-10 mRNA production, inducing an 80-120-fold increase over baseline; in contrast, none of the other cytokines have more than a 2-3-fold effect. In later studies, we showed that the induction of IL-10 mRNA by TNF-alpha is dose- dependent and begins between 8-24 hr following the addition of TNF-alpha; this suggests that the increased IL-10 mRNA level is due to de nova mRNA synthesis rather than mRNA stabilization. Taken together, these results suggest that TNF-alpha plays a key role in the induction of IL-10 in human monocytes; as such, it induces a molecule that provides negative feedback to its sown production. In addition, these studies suggest that TNF-alpha, via its effect on IL-10, may affect overall levels of B cell proliferation.

I) 为了进一步阐明人类 B 细胞同种型分化，我们 定义了 IgG 亚类特异性种系的必要条件 人外周血细胞中转录本（GLT）的产生。 我们发现 各种 IgG 亚类的 GLT 诱导分为两种 模式。 Cgamma3 和 Cgamma1、GLT、基因转录物的诱导 在第一个人类复制单元中，通常需要增殖 刺激 (SAC) 是由 SAC 加 IL-4 (Cgamma3 GLT) 引起的 单独 SAC 或 SAC 加 IL-2 (Cgamma1 GLT)；相反，归纳 Cgamma2 和 Cgamma4 GLT，第二次重复中基因的转录本 单位，仅用细胞因子诱导完成：IFN-gamma（Cgamma2 GLT) 和 IL-4 (Cgamma4 GLT)，并且未通过添加 增殖刺激。 最后，我们发现IFN-γ抑制IL-4- 诱导 Cgamma3 和 Cgamma4 GLT（有或没有 SAC）。 这些发现 确定不同的人类 IgG 亚类表现出不同的特征 同种型早期步骤的调控要求 差异化。 此外，他们认为人类 Cgamma 基因 表现出与其各自基因相关的调控模式 重复单位。 II) IL-10 最近被证明对 人类 B 细胞分化。 想了解一下这个规定 我们测试了单核细胞产生细胞因子的假设 受一种炎症细胞因子的控制。 在初步研究中， 我们将纯化的人外周血单核细胞与一组 细胞因子，包括 TNF-α、IL-1α、IL1-β、IL-6、GM-CSF、TGF- β 和 IFN-α，然后使用半 定量逆转录聚合酶链式反应 (RT-PCR) 技术。 我们发现 TNF-α 对 IL-10 mRNA 有重大影响 产量，比基线增加 80-120 倍；相比之下， 其他细胞因子的效果均不超过 2-3 倍。 稍后在 研究表明，TNF-α 对 IL-10 mRNA 的诱导作用是剂量- 依赖性，并在添加 TNF-α 后 8-24 小时开始； 这表明 IL-10 mRNA 水平增加是由于 de nova mRNA 合成而不是 mRNA 稳定。 综合起来，这些结果 表明TNF-α在IL-10的诱导中起关键作用 人类单核细胞；因此，它会诱导产生负电荷的分子 对其播种产量的反馈。 此外，这些研究表明 TNF-α 通过其对 IL-10 的影响，可能会影响 B 细胞的总体水平 增殖。