Bice D E, Hahn F F, Benson J, Carpenter R L, Hobbs C H
Environ Res. 1987 Aug;43(2):374-89. doi: 10.1016/s0013-9351(87)80038-5.
Some inhaled particles that are deposited in the terminal airways and alveoli clear to the lung-associated lymph nodes, and insoluble particles have a long half-life in these tissues. Because the lung-associated lymph nodes are essential in the induction of immunity after lung immunization, the accumulation of inhaled particles in these tissues could alter immune responses that develop after lung immunization. This study evaluated the effects of inhaled insoluble fly ash particles or alpha quartz on the immune functions of lung-associated lymph nodes. F344 rats were exposed for 20 days by inhalation of fly ash from a fluidized bed combustor (FBC) or a pulverized coal combustor (PCC). Rats were similarly exposed to quartz particles (Min-U-Sil). Control rats were exposed to filtered air. Groups of ten exposed and ten control rats from each group were immunized by intratracheal instillation of 10(8) sheep red blood cells at 4, 6, 40, and 52 weeks after the start of exposures. The cellularity of the lung-associated lymph nodes and antibody-mediated immunity were evaluated at 7 days after immunization. Tissues from lung and lung-associated lymph nodes were taken for histopathology. The inhalation of FBC fly ash, PCC fly ash, and quartz particles all significantly increased the number of lymphoid cells in the lung-associated lymph nodes at each of the sacrifice times. However, FBC fly ash had no significant effect on antibody immunity, while both PCC fly ash and quartz caused suppression of antibody responses at 52 weeks after the start of exposure. Histopathology data showed that exposure to quartz and PCC fly ash caused significant cellular changes in lungs and lung-associated lymph nodes, while FBC fly ash had less effect. These data indicate that an acute exposure (20 days) to relatively insoluble particles significantly increased the cellularity of the lung-associated lymph nodes for up to 52 weeks after the start of the exposure, but the pulmonary toxicity of the particles inhaled appeared to influence the effects of the exposure on antibody immune responses.
一些沉积在终末气道和肺泡中的吸入颗粒会清除至肺相关淋巴结，并且不溶性颗粒在这些组织中的半衰期很长。由于肺相关淋巴结在肺部免疫后诱导免疫中至关重要，吸入颗粒在这些组织中的积累可能会改变肺部免疫后产生的免疫反应。本研究评估了吸入不溶性飞灰颗粒或α-石英对肺相关淋巴结免疫功能的影响。将F344大鼠通过吸入流化床燃烧器（FBC）或粉煤燃烧器（PCC）产生的飞灰暴露20天。大鼠同样暴露于石英颗粒（Min-U-Sil）。对照大鼠暴露于过滤空气。在暴露开始后的第4、6、40和52周，每组10只暴露大鼠和10只对照大鼠通过气管内注入10⁸个绵羊红细胞进行免疫。在免疫后7天评估肺相关淋巴结的细胞数量和抗体介导的免疫。取肺和肺相关淋巴结组织进行组织病理学检查。在每次处死时，吸入FBC飞灰、PCC飞灰和石英颗粒均显著增加了肺相关淋巴结中的淋巴细胞数量。然而，FBC飞灰对抗体免疫无显著影响，而PCC飞灰和石英在暴露开始后52周均导致抗体反应受到抑制。组织病理学数据显示，暴露于石英和PCC飞灰会导致肺和肺相关淋巴结出现显著的细胞变化，而FBC飞灰的影响较小。这些数据表明，急性暴露（20天）于相对不溶性颗粒会在暴露开始后长达52周内显著增加肺相关淋巴结的细胞数量，但吸入颗粒的肺毒性似乎会影响暴露对抗体免疫反应的影响。
