FUNCTIONAL EVALUATION OF MARGINAL ZONE AND B1 B CELLS

拟议研究的长期目标是更好地 了解B细胞亚群对免疫应答的个体贡献。 整体体液反应，并确定是否有明显的B 细胞亚群与自身免疫性疾病有关。 目前， 我们对基本特征和功能的理解 各种B细胞亚群是有限的。 此外，研究 这表明破坏性自身抗体主要来自于 特定的B细胞亚群仍然存在争议。 的一部分 解决这些问题的困难在于缺乏 明确的标记物来描绘不同的B细胞群。 我们 一个实验室发现，低亲和力FceR可能非常有用， 在这方面，由于它将常规B细胞与Ly细胞区分开， 1系和边缘区B细胞。 因此，具体 该提案的目的是：1）确定特定B是否 细胞群体，如由FceR定义的，与 自身抗体的产生。 这将通过仔细 分析15个重组细胞系的B细胞亚群组成， 来自NZB和SM/J亲本的近交系小鼠，以及 这些RI系与NZW小鼠杂交。 遗传 严重自身免疫性疾病的易感性 在RI系中，当小鼠交配时， 到NZW。 2)确定FceR+和FceR- B细胞 对多克隆刺激有不同的反应。 3)确定是否 FceR+和FceR- B细胞对T辅助细胞应答不同 刺激。 4)确定TI-1和TI-2抗原特异性 应答主要来源于FceR-B细胞。 5)更好 了解FceR+和FceR- B细胞的不同作用， 试图获得关于FceR功能的新信息。 这将通过测试FceR在交联至 表面IgM或IgD可调节FceR+ B细胞的活性。 所采用的方法包括广泛使用流式细胞术 为了分析和细胞分选，B细胞的多克隆活化 与抗Ig，LPS和淋巴因子，T细胞依赖性刺激， 具有活化的TH 1和TH 2膜以及淋巴因子的B细胞，以及 抗原特异性刺激B细胞与半抗原化的TI-1和TI- 2种抗原。 该建议的健康相关性是由 从事实上，所有的人都依赖于一个健康， 协调体液反应以产生保护性抗体。 B细胞室不能正常工作不仅 削弱了我们对病原体的反应能力，但也可能导致 破坏性自身免疫性疾病如类风湿性关节炎， 干燥综合征和系统性狼疮。 因此， 对于理解B细胞群体的复杂性至关重要， 以及导致自身抗体产生的条件。

The long term objective of the proposed research is to better understand the individual contributions of B cell subsets to the overall humoral response, and to determine whether a distinct B cell subset is associated with autoimmune disease. At present, our understanding of the basic characteristics and functions of the various B cell subsets is limited. Moreover, studies suggesting that damaging autoantibodies are primarily derived from a particular B cell subset remain controversial. Part of the difficulty in approaching these problems has been the lack of definitive markers to delineate different B cell populations. Our laboratory has found that the low affinity FceR may be quite useful in this regard, as it distinguishes conventional B cells from Ly 1 lineage and marginal zone B cells. Accordingly, the specific aims of the proposal are to: 1) Determine whether a particular B cell population, as defined by the FceR, is associated with the production of autoantibodies. This will be done by carefully analyzing the B cell subset composition of 15 lines of recombinant inbred mice derived from NZB and SM/J parents, and the progeny of these RI lines when crossed with NZW mice. The genetic predisposition for severe autoimmune disease has been segregated among the RI lines, and becomes manifest when the mice are mated to the NZW. 2) Determine whether FceR+ and FceR- B cells differentially respond to polyclonal stimuli. 3) Determine whether the FceR+ and FceR- B cells differentially respond to T helper cell stimuli. 4) Ascertain whether TI-1 and TI-2 antigen-specific responses are primarily derived from FceR-B cells. 5) Better understand the differing roles of FceR+ and FceR- B cells by attempting to gain new information as to the function of the FceR. This will be done by testing whether the FceR, when crosslinked to surface IgM or IgD, can modulated the activity of FceR+ B cells. The methods to be employed include extensive use of flow cytometry for analysis and cell sorting, polyclonal activation of B cells with anti-Ig, LPS and lymphokines, T cell dependent stimulation of B cells with activated TH1 and TH2 membranes plus lymphokines, and antigen-specific stimulation B cells with haptenated TI-1 and TI- 2 antigens. The health relatedness of this proposal is derived from the fact that all individuals depend upon a healthy and coordinated humoral response to produce protective antibodies. Failure of the B cell compartment to function properly not only compromises our ability to respond to pathogens, but can also lead to destructive autoimmune diseases such as rheumatoid arthritis, Sjorgren's syndrome and systemic lupus. Accordingly, it is essential to understand the complexity of the B cell population, and the conditions which lead to the production of autoantibodies.