Czop J K, Austen K F
J Immunol. 1980 Jul;125(1):124-8.
A trypsin-sensitive recognition unit for ingestion of particulate activators of the human alternative complement pathway is present on human monocytes and persists during 48 hr of culture in synthetic medium. Further, after inactivation by trypsin, the recognition unit for activators of the alternative pathway is fully regenerated in terms of function during the 48 hr of culture. In contrast, the C3b receptor on human monocytes is relatively trypsin resistant and is lost during 48 hr of culture, as assessed by its capacity to mediate C3b-dependent immune adherence or enhanced phagocytosis. The prior immune adherence of the monocytes to C3b-bearing particles does not alter the capacity of the monocytes to ingest a particulate activator, and the ingestion of particulate activators does not induce phagocytosis of the rosetted C3b-bearing particles. Thus, the functions linked to the recognition of C3b and of particulate activators of the alternative pathway are expressed independently by monocytes when the determinants reside on separate particles. When the determinants are expressed by the same particle, such as an activator bearing C3b, the monocytes exhibit a synergistic response through their distinct recognition units for C3b and particulate activators of the alternative pathway.
人单核细胞上存在一种对人替代补体途径的颗粒激活剂摄取敏感的胰蛋白酶识别单位，且在合成培养基中培养48小时期间持续存在。此外，经胰蛋白酶灭活后，替代途径激活剂的识别单位在培养48小时期间功能完全再生。相比之下，人单核细胞上的C3b受体对胰蛋白酶相对耐受，并且在培养48小时期间会丧失，这是通过其介导C3b依赖性免疫黏附或增强吞噬作用的能力来评估的。单核细胞先前对携带C3b颗粒的免疫黏附不会改变单核细胞摄取颗粒激活剂的能力，而摄取颗粒激活剂也不会诱导对形成玫瑰花结的携带C3b颗粒的吞噬作用。因此，当决定簇位于不同颗粒上时，单核细胞独立表达与C3b识别以及替代途径颗粒激活剂识别相关的功能。当决定簇由同一颗粒表达时，例如携带C3b的激活剂，单核细胞通过其对C3b和替代途径颗粒激活剂的不同识别单位表现出协同反应。
