Generation and Characterization of Human Cytokine-Producing B Cell Effectors

项目摘要 B细胞对于保护性免疫的产生和在多个离散阶段的功能是重要的。的 认识到B细胞作为抗体产生细胞所发挥的独特作用，然而B细胞的其它功能 作为抗原呈递细胞，淋巴组织者和产生精氨酸的效应细胞或调节细胞， 更少被理解和研究。本实验室最近的工作表明，产生细胞因子的效应子B 细胞在对感染因子的保护性体液和细胞免疫的发展中起着至关重要的作用。我们 因此，假设有专门的B细胞群，具有分泌 细胞因子和调节免疫反应。为了解决这个假设，我们开发了一种体外培养， 使用原代小鼠B细胞产生不同种类细胞因子产生效应B细胞的系统。我们 表征了这些体外产生的细胞，并发现了我们随后用来鉴定 体内产生细胞因子的B细胞亚群。例如，使用我们在体外培养中鉴定的标记， 我们现在可以在体内鉴定产生IFN的B细胞效应物，并表明这些B细胞特异性地 流感感染后诱导，并且在一些自身免疫小鼠模型中数量增加。 因此，这种方法使我们第一次能够在体内观察B细胞效应子，并打开了研究的大门。 功能和机制研究的大门，将揭示这些细胞在感染和自身免疫中的作用， 疾病尽管我们在小鼠效应B细胞的研究中取得了重大进展， 对人类B细胞的了解。事实上，只有非常初步的研究已经进行， 与人类B细胞的约会。从这些有限的研究中可以清楚地看到，人类B细胞具有制造 在某些刺激条件下。然而，这些研究都是用散装的 外周血B细胞，因此效应人B细胞亚群仍有待鉴定。这个的目标 建议是：（i）开发体外培养系统，以表型和功能表征人 效应B细胞和（ii）使用我们从体外培养中获得的信息来鉴定 来自健康和自身免疫个体的样品中的效应B细胞。

Project Summary B cells are important for the generation of protective immunity and function at multiple discrete stages. The unique role that B cells play as antibody-producing cells is appreciated, however the other functions of B cells as antigen presenting cells, lymphoid tissue organizers and cytokine-producing effector or regulatory cells are much less understood and rarely studied. Recent work from our lab showed that cytokine producing effector B cells play crucial roles in the development of protective humoral and cellular immunity to infectious agents. We therefore hypothesized that there are specialized populations of B cells that have the ability to secrete cytokines and regulate immune responses. To address this hypothesis, we developed an in vitro culture system using primary mouse B cell to generate different classes of cytokine producing effector B cells. We characterized these in vitro generated cells and found markers that we subsequently used to identify the cytokine producing B cell subpopulations in vivo. For example, using markers identified in our in vitro cultures, we can now identify IFNγ producing B cell effectors in vivo and showed that these B cells are specifically induced in response to influenza infection and are elevated in number in some mouse models of autoimmunity. Thus, this approach has allowed us for the first time to visualize B cell effectors in vivo and has opened the door to functional and mechanistic studies that will reveal the roles for these cells in infectious and autoimmune disease. Despite the significant progress that we have made in our studies of mouse effector B cells, little is known about their human B cell counterparts. In fact, only very rudimentary studies have been conducted to date with human B cells. From these limited studies it is clear that human B cells have the potential to make cytokines under some stimulation conditions. However, these studies have been conducted with bulk peripheral blood B cells, thus the effector human B cells subsets remain to be identified. The goals of this proposal are to (i) to develop an in vitro culture system to phenotypically and functionally characterize human effector B cells and (ii) To use the information that we have obtained from the in vitro cultures to identify effector B cells in samples from healthy and autoimmune individuals.