INHERITED CONTROL MECHANISMS IN IG GENE EXPRESSION

本研究的主要目的是研究T细胞 对自身和非自身免疫球蛋白的反应。 IgG2a 抗原在Ia B淋巴瘤细胞中天然表达， 完全能够进行抗原呈递， 抗原易于使用重组DNA技术操作 使该系统具有独特的优势， 复杂的细胞内运输途径之间的关系 和MHC限制特异性。 我们计划构建pSV 2gt 编码各种形式的C57 BL/6 IgG 2ab CH 3的载体。 我们 对分子的这一部分特别感兴趣， Igh-1b特异性T细胞识别的同种异型决定簇是 位于CH 3结构域。 可溶性、膜结合和细胞质 C57 BL/6 IgG 2ab CH 3的形式将在转染的细胞中表达。 B淋巴瘤细胞系。 我们将对蛋白质产品进行表征 来测试这些分子是否 II类限制性T细胞 一个主要目标是确定 内源性合成的IgG 2a抗原是否与 II类分子的细胞内。 我们还将表达 VMPC 11-C57 BL/6人B-控制下的IgG 2ab CH 3蛋白 肌动蛋白启动子在多种不同类型的Ia+ APC系中， 检测不同类型Ia+是否合成内源性IgG 2a APC将刺激Igh-1b特异性T细胞。 总体而言，这些 实验将有望导致更清楚地了解 抗原提呈细胞在MHC限制性T细胞中的作用 自身免疫球蛋白的识别和参与T 细胞耐受性

The broad objective of this research is to investigate T cell responses to self and nonself immunoglobulins. The fact that IgG2a antigens are naturally expressed in Ia B lymphoma cells known to be fully capable of antigen presentation and that the structure of the antigen is readily manipulated using recombinant DNA techniques gives this system unique advantages for studying possible relationships between complex intracellular trafficking pathways and MHC restriction specificity. We plan to construct pSV2gt vectors encoding various forms of the C57BL/6 IgG2ab CH3. We are particularly interested in this portion of the molecule because allotypic determinants recognized by Igh-1b-specific T cell are located in the CH3 domain. Soluble, membrane-bound,and cytoplasmic form(s) of the C57BL/6 IgG2ab CH3 will be expressed in transfected B lymphoma cell lines. We will characterize the protein products that are synthesized and test whether these molecules are presented to Class II-restricted T cells. A major goal is to determine whether endogenously synthesized IgG2a antigens become associated with Class II molecules intracellularly. We will also express the VMPC11 -C57BL/6 IgG2ab CH3 protein under control of the human B- actin promoter in a variety of different types of Ia+ APC lines to test whether endogenous IgG2a synthesized by different types of Ia+ APC will stimulate Igh-1b-specific T cells. Overall, these experiments will hopefully lead to a clearer understanding of the possible role of antigen-presenting cells in MHC-restricted T cell recognition of self immunoglobulins and processes involved in T cell tolerance.