Morton H
Aust J Biol Sci. 1984;37(5-6):393-407. doi: 10.1071/bi9840393.
Early pregnancy factor (EPF) is a pregnancy-dependent, suppressor-releasing hormone, which can be differentiated from other known pregnancy-associated substances by its physiological, biochemical and immunological characteristics. To date studies have shown that the presence of EPF in serum at anytime except during pregnancy is pathological and is associated with tumors of germ cell origin. EPF can be detected in serum within hours of fertilization, thus providing for the first time a means of monitoring in vitro the continuing viability of a fertilized egg in vivo. EPF has been shown to be a link between fertilization and immunomodulation. Fertilization of the ovum initiates a chain of events which includes production of EPF. EPF then binds to lymphocytes, releasing soluble suppressor substances, which in turn modulate the mother's immune system. Thus it is proposed that the conceptus ensures its own defence against immunological rejection.
早孕因子（EPF）是一种依赖于妊娠的抑制因子释放激素，根据其生理、生化和免疫学特征，可与其他已知的妊娠相关物质区分开来。迄今为止的研究表明，除妊娠期间外，血清中任何时候出现EPF都是病理性的，且与生殖细胞起源的肿瘤有关。受精后数小时即可在血清中检测到EPF，从而首次提供了一种在体外监测受精卵在体内持续存活能力的方法。EPF已被证明是受精与免疫调节之间的一个环节。卵子受精引发一系列事件，其中包括EPF的产生。然后EPF与淋巴细胞结合，释放可溶性抑制物质，进而调节母亲的免疫系统。因此，有人提出，孕体可确保自身抵御免疫排斥。
