MECHANISM OF CIGARETTE SMOKE-INDUCED IMMUNOSUPPRESSION

吸烟会增加患上呼吸道疾病的风险 呼吸道感染、几种器官的癌症和心血管疾病。 为了确定这种感染易感性的增加是否相关 通过香烟烟雾引起的免疫系统的变化，我们研究了 吸烟对啮齿动物的影响。我们的结果表明，慢性 大鼠/小鼠暴露于来自R1香烟的香烟烟雾(高焦油，高焦油) 尼古丁，肯塔基大学参考香烟)主要影响 B淋巴细胞功能。此外，B细胞的反应，最容易受到 香烟烟雾是那些通过抗原受体激活的烟雾。 (表面免疫球蛋白的交联)。这项提议的目标是 为了：(A)了解免疫抑制的潜在机制(S) 香烟烟雾的影响，以及(B)确定香烟的特定成分 香烟烟雾冷凝物是造成观察到的 免疫抑制。 本文提出的实验旨在评估 吸烟对B细胞增殖和已知阶段的影响 差异化。烟雾暴露和假对照组动物的B细胞将 检测它们的激活能力，受体交联性， 磷脂酰肌醇的代谢，包括酪氨酸的激活 磷酸激酶(使用抗磷酸化酪氨酸单抗进行蛋白质印迹分析)， 磷脂酶C(肌醇磷酸盐的代谢) 细胞内钙含量(Indo-1荧光变化)，以及 蛋白激酶C的激活(32P标记)。流式细胞术，使用 将使用吖啶橙染色来确定细胞周期时相。 已知与淋巴细胞激活相关的原癌基因的激活， 与c-fos和c-myc一样，将用~(32)P- 标记的cdna探针。此外，还将检查B细胞的 产生免疫球蛋白的能力(用ELISA法测定) 抗原/有丝分裂原激活以及在存在或不存在的情况下 淋巴因子，如IL-4、IL-5、IL-6和tau-干扰素。 将使用已建立的协议来获得分数和次分数 香烟烟雾冷凝物。这些分数将合并到 恒定释放惰性微丸(含有特定组分的微丸将 由美国创新研究公司制造，俄亥俄州托莱多)，植入 皮内传播到动物体内，对免疫系统的影响在监测 植入后不同时间。有效分数将进一步 评估它们在体外影响淋巴细胞功能的能力。 这些实验的结果可能会提供关于这种方式的想法 香烟烟雾会影响免疫系统。的适用性。 最近的结果加强了对人类吸烟者的这些结果 来自Weissman等人。(见附录1)香烟烟雾影响 人类免疫系统的方式类似于我们在我们的 实验室里，在老鼠身上。

Cigarette smoking is associated with elevated risks of upper respiratory tract infections, cancers of several organs, and cardiovascular disease. To determine whether this increased susceptibility to infections correlated with cigarette smoke-induced changes in the immune system, we studied the effects of cigarette smoke in rodents. Our results indicated that chronic exposure of rats/mice to cigarette smoke from R1 cigarettes (high tar, high nicotine, University of Kentucky Reference Cigarette) affects primarily the B lymphocyte function. Moreover, the B cell responses, most susceptible to cigarette smoke, are those which are activated via the antigen receptors (cross-linking of surface immunoglobulins). The goals of this proposal are to: (a) understand the underlying mechanism(s) for the immunosuppressive effects of cigarette smoke, and (b) to identify specific components of cigarette smoke condensate that are responsible for the observed immunosuppression. Experiments proposed herein are directed at evaluating the effects of cigarette smoke on the known stages of B cell proliferation and differentiation. B cells from smoke-exposed and sham control animals will be examined for their ability to activate, receptor crosslinking-dependent, metabolism of phosphatidylinositol, including activation of tyrosine phosphokinase (western blot analysis using mAb to phosphotyrosines), phospholipase C (metabolism of inositol phosphates), increase in intracellular calcium content (changes in indo-1 fluorescence), and the activation of protein kinase C (32P-labeling). Flow cytometry, using acridine orange staining will be employed to determine cell cycle phases. Activation of protooncogenes known to correlate with lymphocyte activation, like c-fos and c-myc, will be assayed by northern blotting using 32P- labeled cDNA probes. In addition, B cells will be examined for their ability to produce immunoglobulin (assayed by ELISA) in response to antigenic/mitogenic activation, and in the presence or absence of lymphokines such as IL4, IL5, IL6, and tau-IFN. Established protocols will be employed to obtain fractions and subfractions of cigarette smoke condensate. These fractions will be incorporated into constant-release inert pellets (pellets containing specific fractions will be made by Innovative Research of America, Toledo, OH), implanted intradermally into animals, and effects on the immune system monitored at various times after implantation. The effective fractions will be further evaluated for their ability to influence lymphocyte functions in vitro. Results from these experiments are likely to provide ideas abut the manner in which cigarette smoke affects the immune system. The applicability of these results to human smokers has been strengthened by the recent results from Weissman et al. (see Appendix 1) in which cigarette smoke affects the human immune system in a manner similar to those observed, in our laboratory, in the rat.