Lamerz R, Fateh-Moghadam A
Klin Wochenschr. 1975 Feb 15;53(4):147-69. doi: 10.1007/BF01466760.
Alpha-fetoprotein (AFP) is an alpha1-glycoprotein (M.W. about 65000) appearing in the fetal serum of most mammals including man during the early stages of pregnancy; 4 weeks after birth it disappears altogether or exists at very low concentrations as in the normal adult. AFP is formed in the yolk sac, the fetal liver and the gastro-intestinal tract. One of its physiological functions in fetal life is supposed to be the protection of the fetus from maternal oestrogens (oestrophilic property). The clinical significance of AFP is based on the regular and increasing production in primary liver cell carcinoma, less frequently in teratogenetic tumors where it serves as a control of therapy and course of the disease. Less frequent, minor and temporary increases in the AFP serum level occur in several primary tumors with secondary liver involvement, and in inflammatory gastro-intestinal diseases, e.g. of the liver (hepatitis, cirrhosis). AFP has an increasing importance in gynecology (gestational age, fetal distress syndrom, malformations, hydatidiform mole/chorion carcinoma). The physico-chemical properties of AFP are widely known. Both fetal and tumor AFP appear to be immunologically and biochemically identical, as are that of tissue and biological fluids. The differences observed (variants, microheterogeneity) depend mainly on the different content of sialic acid. An antigenetic relationship exists, between the AFP of most species. The immunodiffusion (Ouchterlony) is the most frequently used but relatively insensitive test (1-5 mug/ml) in finding AFP, whereas the radioimmunoassay is the most sensitive one (up to 0,25 ng/ml) and permits the determination of normal serum levels in adults (below 20 ng/ml). The serum concentration in healthy pregnant women lies up to 500 ng/ml, in patients with hepatitis, liver cirrhosis and other liver diseases mostly under 3 mug/ml, whereas in those with primary liver cell carcinoma levels up to and above 600 mg-percent have been found.
甲胎蛋白（AFP）是一种α1糖蛋白（分子量约65000），在包括人类在内的大多数哺乳动物的孕期早期，会出现在胎儿血清中；出生4周后，它会完全消失，或者像正常成年人那样以极低浓度存在。AFP在卵黄囊、胎儿肝脏和胃肠道中形成。它在胎儿期的生理功能之一被认为是保护胎儿免受母体雌激素的影响（亲雌激素特性）。AFP的临床意义在于，原发性肝细胞癌中其产生通常会规律且不断增加，在畸胎瘤中则较少见，在畸胎瘤中它可用于监测治疗和疾病进程。在一些有继发性肝脏受累的原发性肿瘤以及炎症性胃肠道疾病（如肝脏疾病，如肝炎、肝硬化）中，AFP血清水平会出现不太常见、轻微且短暂的升高。AFP在妇科领域（孕周、胎儿窘迫综合征、畸形、葡萄胎/绒毛膜癌）的重要性日益增加。AFP的物理化学性质广为人知。胎儿和肿瘤来源的AFP在免疫和生化方面似乎是相同的，组织和生物体液中的AFP也是如此。观察到的差异（变体、微异质性）主要取决于唾液酸含量的不同。大多数物种的AFP之间存在抗原关系。免疫扩散（奥克特洛尼法）是检测AFP时最常用但相对不敏感的方法（检测限为1 - 5微克/毫升），而放射免疫测定是最敏感的方法（检测限可达0.25纳克/毫升），可用于测定成年人的正常血清水平（低于20纳克/毫升）。健康孕妇的血清浓度可达500纳克/毫升，肝炎、肝硬化和其他肝脏疾病患者大多低于3微克/毫升，而原发性肝细胞癌患者的水平可达600毫克%及以上。
