REGULATION OF B CELL FUNCTION BY INTERLEUKIN 12

描述（改编自研究者摘要）：本研究的目的 研究是为了确定体内施用白细胞介素-12 IL-12将在T细胞非依赖性免疫应答期间改变细胞因子表达 提高多糖疫苗接种的有效性 抗原 IL-12可能特别有益于增强 肺炎球菌和脑膜炎球菌多糖疫苗， 刺激γ-干扰素的产生， 有效介导抗细菌免疫的抗体同种型。 对于本研究中的实验，BALB/c和C57 BL/6小鼠将被 用IL-12和多糖疫苗接种， 此后将在不同时间监测细胞因子和抗体。 的 将检测IL-12引起细胞因子RNA表达变化的能力 通过RT-PCR和核糖核酸酶保护测定。 水平和特异性 将使用同种型特异性ELISA定量诱导的抗体。 可能导致观察到的效应的中间细胞因子将 使用细胞因子基因靶向破坏的小鼠进行鉴定， 内源性IL-12在调节反应性中的作用将使用 IL-12敲除小鼠。 缺乏特异性淋巴细胞的免疫缺陷小鼠 将利用子集来确定IL-12的作用是否是由于 活化的NK细胞或通过结合 B细胞IL-12受体。 的生物学功能 诱导的抗体将通过补体结合来确定， 针对靶细菌菌株的调理素作用测定。 最后 IL-12增强对致死性肺炎球菌的体内保护的能力 和脑膜炎球菌感染将通过直接接种 毒性细菌菌株注入接种的小鼠。 感染由S。 肺炎和N.脑膜炎是肺炎的主要原因， 脑膜炎和中耳炎，估计每年造成750万例病例， 美国和全球每年超过1亿例。 目前的疫苗是 只有有限的效力。 因此，IL-12作为疫苗佐剂的用途 可能为预防这些疾病提供一种新的方法， 对人类健康有直接影响。

DESCRIPTION (Adapted from Investigator's abstract): The purpose of this study is to determine whether in vivo administration of interleukin-12 (IL-12) will shift cytokine expression during T-independent immune responses and enhance the effectiveness of vaccination against polysaccharide antigens. IL-12 may be especially beneficial for enhancing the usefulness of pneumococcal and meningococcal polysaccharide vaccines, since it stimulates production of interferon-gamma and increases secretion of antibody isotypes that are efficient in mediating anti-bacterial immunity. For the experiments in this study, BALB/c and C57BL/6 mice will be inoculated with IL-12 and polysaccharide vaccine, and levels of induced cytokines and antibodies will be monitored at various times thereafter. The ability of IL-12 to cause shifts in cytokine RNA expression will be examined by RT-PCR and ribonuclease protection assays. The levels and specificities of induced antibodies will be quantitated using isotype-specific ELISAs. Intermediary cytokines potentially responsible for the observed effects will be identified using mice with targeted disruptions in cytokine genes and the role of endogenous IL-12 in regulating responsiveness will be examined using IL-12 knockout mice. Immunodeficient mice lacking specific lymphoid cell subsets will be exploited to determine whether the effect of IL-12 are due to activated NK cells or to direct stimulation of B-cells through binding to the newly described B-cell IL-12 receptor. The biological functions of the induced antibodies will be determined by complement fixation and opsonization assays against the target bacterial strains. Finally, the ability of IL-12 to enhance in vivo protection against lethal pneumococcal and meningococcal infections will be tested by direct inoculation of virulent bacterial strains into vaccinated mice. Infections due to S. pneumonia and N. meningitidis are the leading causes of pneumonia, meningitis, and otitis media, causing an estimated 7.5 million cases/year in the U.S. and over 100 million cases/year worldwide. Current vaccines are of only limited effectiveness. Thus, the use of IL-12 as a vaccine adjuvant may provide a novel approach for protection against these diseases and could have immediate impact on human health.