CHARACTERIZATION OF MURINE AND HUMAN IG-D-RECEPTORS ON T

先前的观察已经建立了寡聚体快速上调的机制 或交叉连接的，但不是单体的IGD受体(IGD-R) 大比例的小鼠和人外周T细胞和辅助T细胞 克隆人。T细胞上的IGD-R也可通过抗CD3刺激而诱导， IL-2、IL-4、干扰素-γ和其他途径刺激剂，如 PMA+离子载体。除IL-2和Alternate外的许多试剂 途径刺激剂不能上调老年小鼠T细胞上的IGD-R。 鉴于年轻人IGD-R+T细胞的免疫增强特性，但 在老年小鼠中，这些IGD-R似乎不能稳定/促进T-B细胞 相互作用，特别是与含有交联面IGD的B细胞。 小鼠和人类辅助T杂交瘤细胞也表达IGD-R并释放 可溶性免疫球蛋白结合因子(IGD-BF)与其上清液的结合 IL-2、IL-4或交联型IGD的影响。小鼠IGD-R+受体是 40kD的分子可被IGD-Sepharose特异性沉淀。 这些分子以及分离的人IGD-R将被提纯并 进行部分氨基酸序列测定。每个细胞的IGD-R数量 将在正常T细胞、经IGD处理的T细胞和T杂交瘤上进行定量 细胞。目前已有针对人IGD-R/BF(LTB9)的抗体， 针对小鼠IGD-R/BF的抗体正在进行特异性评估。 对人和小鼠IGD-R/BF基因的克隆进行了探讨 利用现有的活化T细胞基因文库。更多的研究将 关注鼠和人IGD-R的良好特异性：观点 最近的发现表明IGD上的N-糖链与 小鼠IGD-R，这些多糖的功能作用将被研究。 将特别注意碳水化合物决定因素的作用。 人IGD与人T细胞IGD-R结合的研究

Previous observations have established the rapid upregulation by oligomeric or cross-linked, but not monomeric, IgD of receptors for IgD (IgD-R) on a large percentage of murine and human peripheral T cells and helper T cell clones. IgD-R on T cells are also induced by stimulation with anti-CD3, IL-2, IL-4, IFN-gamma, and alternate pathway stimulating agents, such as PMA + ionophore. Many of these reagents, except for IL-2 and alternate pathway stimulators, fail to upregulate IgD-R on T cells from aged mice. In view of the immunoaugmenting properties of IgD-R+ T cells in young, but not in aged mice, these IgD-R appear to stabilize/promote T-B cell interaction, particularly with B cells bearing cross-linked surface IgD. Murine and human helper T hybridoma cells also express IgD-R and release soluble binding factors for IgD (IgD-BF) into their supernatants under the influence of IL-2, IL-4 or crosslinked IgD. Murine IgD-R+ receptors are 40kD molecules that can be specifically precipitated by IgD-Sepharose. These molecules, as well as isolated human IgD-R will be purified and subjected to partial amino acid sequencing. The numbers of IgD-R per cell will be quantitated on normal T cells, IgD-treated T cells and T hybridoma cells. Antibodies to the human IgD-R/BF (LTB9) are available and antibodies to the murine IgD-R/BF are being evaluated for specificity. Cloning of the cDNA of the human and murine IgD-R/BF will be approached using available activated T-cell cDNA libraries. Additional studies will concern the fine specificity of both the murine and human IgD-R: In view of recent findings implicating N-glycans on IgD in its binding to the murine IgD-R, the functional role of these glycans will be investigated. Particular attention will be given to the role of carbohydrate determinants on human IgD in its binding to the human T cell IgD-R.