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。这个 B细胞作为抗体产生细胞的独特作用受到重视，但B细胞的其他功能 作为抗原提呈细胞、淋巴组织组织者和细胞因子产生的效应者或调节细胞 更少人了解，也很少研究。我们实验室最近的研究表明，产生细胞因子的效应器B 细胞在发展对感染性病原体的保护性体液和细胞免疫中起着至关重要的作用。我们 因此假设存在特殊的B细胞群体，它们具有分泌 细胞因子和调节免疫反应。为了解决这一假设，我们开发了一种体外培养 该系统利用原代小鼠B细胞产生不同类别的细胞因子，产生效应性B细胞。我们 对这些体外产生的细胞进行了表征，并找到了我们随后用来识别 体内产生B细胞亚群的细胞因子。例如，使用我们的体外培养中识别的标记， 我们现在可以在体内识别产生干扰素的B细胞效应器，并表明这些B细胞是特异的 在对流感感染的反应中诱导，并在某些自身免疫的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可视化B细胞效应器，并打开了 进行功能和机制研究，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，但几乎没有 已经知道了他们的人类B细胞对应物。事实上，只进行了非常初级的研究，以 与人类B细胞约会。从这些有限的研究中可以清楚地看出，人类B细胞有可能使 某些刺激条件下的细胞因子。然而，这些研究都是批量进行的。 外周血液中的B细胞，因此人类B细胞亚群的效应者仍有待鉴定。这样做的目的是 建议是(I)开发一种体外培养系统，以表型和功能表征人类 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 健康人和自身免疫者样本中的效应器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.