Anti-Inflammatory mechanisms of soybean-derived Bowman-Birk protease inhibitor

描述（由申请人提供）：Bowman-Birk Inhibitor （BBI）是一种从大豆中提取的口服活性丝氨酸蛋白酶抑制剂。BBIC浓缩物（BBIC）是富含BBI的大豆提取物。在非神经系统自身免疫性疾病的人体试验中，BBIC已被证明具有有效的抗炎作用而无相关毒性。我们已经证明，在几种啮齿动物模型中，口服BBI/BBIC可显著减少中枢神经系统的自身免疫性炎症。在发病后，当临床缺陷已经形成时，给予BBI可迅速改善临床症状，防止疾病进展，这一点具有重要意义。BBI治疗的这一特点是其适合治疗已经表现出疾病临床症状的患者的核心。尽管BBIC已经过临床试验，但其在神经和非神经自身免疫性疾病中的抗炎作用机制尚不清楚。本研究采用CD4+T细胞为主介导的多发性硬化症（MS）小鼠模型和CD8+T细胞为主介导的糖尿病模型，研究BBI对体内和体外免疫细胞的影响。在具体目标1中，我们将验证IL-10产生增加是EAE中BBI抗炎作用的重要机制的假设。这一假设是基于我们在体内和体外发现BBI诱导免疫细胞产生IL-10。已证实BBI可抑制抗原加工，但其对抗原提呈细胞功能的影响尚不清楚。在目标2中，我们将检验BBI抑制抗原呈递的假设。到目前为止，还没有研究表明BBI对T细胞的直接影响。考虑到T细胞在适应性免疫中的关键作用，在aim 3中，我们将检验BBI直接抑制T细胞的假设。我们期望这些研究将对BBI抗炎作用的机制方面产生深入的见解，并促进其作为MS以及其他炎症疾病的补充治疗。

DESCRIPTION (provided by applicant): Bowman-Birk Inhibitor (BBI) is an orally active serine protease inhibitor derived from soybeans. BBI concentrate (BBIC) is an extract of soybeans enriched in BBI. In human trials for non-neurological autoimmune disorders, BBIC has been shown to exert potent anti-inflammatory effects without associated toxicity. We have shown that in several rodent models oral BBI/BBIC dramatically reduced autoimmune inflammation of the central nervous system. It is of major significance that after disease onset, when clinical deficits have already developed, administration of BBI rapidly ameliorated clinical signs and prevented disease progression. This feature of BBI therapy is central to its suitability for treating patients who have already shown clinical signs of disease. Even though BBIC has been clinically tested, mechanisms of its anti-inflammatory action are poorly understood in both neurological and non-neurological autoimmune diseases. Here we propose to investigate effects of BBI on immune cells in vivo and in vitro using a mouse model of multiple sclerosis (MS) mediated predominantly by CD4+T cells, and a model of diabetes mediated predominantly by CD8+T cells. In specific aim 1 we will test the hypothesis that increase in IL-10 production is an important mechanism for anti-inflammatory effects of BBI in EAE. This hypothesis is based on our discovery that BBI induces IL-10 production by immune cells in vivo and in vitro. It has been shown that BBI inhibits antigen processing, but its effect on functions of antigen presenting cells is unknown. In aim 2 we will test the hypothesis that BBI suppresses antigen presentation. Thus far, there is no study that addresses direct effects of BBI on T cells. Taking in account the crucial role of T cells in adaptive immunity, in aim 3 we will test the hypothesis that BBI directly suppresses T cells. We expect that these studies will yield in depth insights into mechanistic aspects of anti-inflammatory actions of BBI, and facilitate its use as a supplementary treatment for MS, as well as other inflammatory conditions. Public Health Relevance: Bowman-Birk Inhibitor (BBI) is an orally active protease inhibitor from soybeans. In human trials for autoimmune disorders, BBI has been shown to have anti-inflammatory effects without associated toxicity. Even though BBI has already been clinically tested, mechanisms of its anti-inflammatory action are poorly understood. Here we propose to investigate effects of BBI on immune cells in experimental models of multiple sclerosis and diabetes. In our previous study we discovered that BBI increases production of interleukin 10 (IL-10). IL-10 has well known anti-inflammatory properties, and we will investigate if this molecule plays a role in beneficial effects of BBI. Published data and preliminary studies indicate that BBI has an effect on two crucial types of immune cells; so called antigen presenting cells and T cells. The second portion of this proposal is dedicated to mechanistic studies of effects that BBI has on these cells. We believe that these studies will provide in depth insights into anti-inflammatory actions of BBI, and facilitate its use as a supplementary treatment for inflammatory diseases.