Loegering D J, Commins L M, Minnear F L, Gary L A, Hill L A
Infect Immun. 1987 Sep;55(9):2074-80. doi: 10.1128/iai.55.9.2074-2080.1987.
The phagocytosis of erythrocytes by macrophages has previously been shown to depress macrophage function. In this study we compared the effect of the phagocytosis of erythrocytes and erythrocyte ghosts by Kupffer cells on the duration of the depression of complement receptor clearance function and host defense against endotoxemia and bacteremia. Phagocytosis of erythrocytes and erythrocyte ghosts was induced in rats by the injection of rat erythrocytes or erythrocyte ghosts coated with anti-rat erythrocyte immunoglobulin G (EIgG and GIgG, respectively). The hepatic uptake of EIgG and GIgG (17.4 X 10(8)/100 g) occurred during the first 30 min after injection. The digestion of phagocytized EIgG and GIgG, as assessed by electron microscopy, was complete at 24 and 3 h after injection, respectively. The depression of Kupffer cell complement receptor clearance function caused by EIgG and GIgG returned to normal by 6 h after injection of EIgG and by 3 h after injection of GIgG. Phagocytosis of EIgG depressed the survival rate after endotoxemia and bacteremia when endotoxin or bacteria were injected at 30 min after EIgG. The survival rate returned to normal when the endotoxin and bacteria were injected at 12 and 6 h after the EIgG, respectively. Phagocytosis of GIgG did not depress the survival rate after endotoxemia and bacteremia. Thus, compared with erythrocytes, erythrocyte ghosts are more rapidly digested after phagocytosis, depress complement receptor function for a shorter period of time, and cause less depression of host defense. These findings indicate that the contents of erythrocytes play an important role in the impairment of host defense caused by the phagocytosis of erythrocytes by Kupffer cells.
巨噬细胞对红细胞的吞噬作用此前已被证明会抑制巨噬细胞功能。在本研究中，我们比较了库普弗细胞对红细胞和红细胞影的吞噬作用对内毒素血症和菌血症时补体受体清除功能抑制持续时间以及宿主防御的影响。通过注射分别包被有抗大鼠红细胞免疫球蛋白G（分别为EIgG和GIgG）的大鼠红细胞或红细胞影，诱导大鼠吞噬红细胞和红细胞影。注射后最初30分钟内发生EIgG和GIgG的肝脏摄取（17.4×10⁸/100g）。通过电子显微镜评估，吞噬的EIgG和GIgG分别在注射后24小时和3小时完全消化。EIgG和GIgG引起的库普弗细胞补体受体清除功能抑制在注射EIgG后6小时和注射GIgG后3小时恢复正常。当在注射EIgG后30分钟注射内毒素或细菌时，EIgG的吞噬作用会降低内毒素血症和菌血症后的存活率。当分别在注射EIgG后12小时和6小时注射内毒素和细菌时，存活率恢复正常。GIgG的吞噬作用不会降低内毒素血症和菌血症后的存活率。因此，与红细胞相比，红细胞影在吞噬后消化更快，补体受体功能抑制时间更短，对宿主防御的抑制作用更小。这些发现表明，红细胞的内容物在库普弗细胞吞噬红细胞所致宿主防御损害中起重要作用。
