Wright P F, Stacey N H
National Institute of Occupational Health and Safety, University of Sydney, NSW, Australia.
Carcinogenesis. 1991 Aug;12(8):1365-70. doi: 10.1093/carcin/12.8.1365.
The natural killer (NK) and natural cytotoxic (NC) cell activities in livers from certain rat and mouse strains were compared. This included the two rodent strains used in animal carcinogenicity bioassays, i.e. Fischer 344 and B6C3F1 mice. Sprague-Dawley and Fischer 344 rats exhibited high hepatic NK activity, which was greater than the levels seen in all of the five mouse strains studied. However, the hepatic NC activity in rats was comparable to the activities observed in C57BL and BALB/c mice. An inverse relationship was observed between the two tumoricidal activities in all but one of the mouse strains examined; that is (at 8 weeks of age), NK activity: C3H greater than B6C3F1 greater than CBA greater than BALB/c; NC activity: BALB/c much greater than CBA greater than B6C3F1 greater than C3H. The C57BL mouse strain was the only strain to express both activities at comparatively high levels. Female mice exhibited a similar profile of cytotoxic activities. Rats also possessed high activities of a presently ill-defined tumoricidal activity, this being the spontaneous P815 mastocytoma killing by unstimulated effector cells, over an 18 h period. Both adherent and nonadherent effector cells from rat livers, but only the nonadherent cell population isolated from male mouse livers, exhibited this activity which may represent a distinct hepato-specific population of natural lymphocytotoxic effector cells. The tumoricidal activities in liver-derived cells were greater than those of effector cells isolated from the spleen. The differences in natural immunity reported in this study may be related to the varying background incidences of hepatic tumors, i.e. the mouse strains susceptible to high background incidences of liver tumors have relatively low natural immunity, whereas the two mouse strains resistant to hepatic tumors possess high levels of at least one hepatic NLC activity. Similarly, rats have relatively low hepatic tumor rates and high levels of hepatic natural immunity.
比较了某些大鼠和小鼠品系肝脏中的自然杀伤（NK）细胞和自然细胞毒性（NC）细胞活性。这包括用于动物致癌性生物测定的两种啮齿动物品系，即Fischer 344和B6C3F1小鼠。Sprague-Dawley和Fischer 344大鼠表现出较高的肝脏NK活性，高于所研究的所有五个小鼠品系中的水平。然而，大鼠肝脏中的NC活性与C57BL和BALB/c小鼠中观察到的活性相当。在所检查的除一个小鼠品系外的所有品系中，观察到两种杀肿瘤活性之间呈负相关；即（8周龄时），NK活性：C3H＞B6C3F1＞CBA＞BALB/c；NC活性：BALB/c＞＞CBA＞B6C3F1＞C3H。C57BL小鼠品系是唯一在相对高水平表达两种活性的品系。雌性小鼠表现出类似的细胞毒性活性谱。大鼠还具有目前定义不明确的高杀肿瘤活性，这是未刺激的效应细胞在18小时内对自发P815肥大细胞瘤的杀伤作用。来自大鼠肝脏的贴壁和非贴壁效应细胞，但只有从雄性小鼠肝脏分离的非贴壁细胞群体表现出这种活性，这可能代表一种独特的肝特异性自然淋巴细胞毒性效应细胞群体。肝脏来源细胞中的杀肿瘤活性大于从脾脏分离的效应细胞。本研究中报道的自然免疫差异可能与肝脏肿瘤的不同背景发生率有关，即易患肝脏肿瘤高背景发生率的小鼠品系自然免疫相对较低，而对肝脏肿瘤有抗性的两个小鼠品系至少具有高水平的一种肝脏NLC活性。同样，大鼠肝脏肿瘤发生率相对较低，肝脏自然免疫水平较高。
