Hill D J, Tevaarwerk G J, Arany E, Kilkenny D, Gregory M, Langford K S, Miell J
Medical Research Council Group in Fetal and Neonatal Health and Development, Lawson Research Institute, St. Joseph's Health Center, London, Ontario, Canada.
J Clin Endocrinol Metab. 1995 Jun;80(6):1822-31. doi: 10.1210/jcem.80.6.7539816.
Fibroblast growth factor-2 (FGF-2) is expressed in human fetal tissues and placenta. We, therefore, determined whether FGF-2 appeared in either fetal or maternal circulations during normal pregnancies [fetuses appropriate for gestational age (AGA)] or those complicated by fetal growth restriction (small for gestational age). Cordocentesis was performed, and matched maternal blood was collected between 19-39 weeks gestation, whereas maternal and cord blood and amniotic fluid (AF) were collected at term. FGF-2 was extracted from maternal serum (MS), cord serum (CS), and AF by heparin-Sepharose affinity chromatography and subjected to Western blot analysis or quantified by specific RIA. Western blot analysis of MS, CS, and AF revealed, in each case, a single immunoreactive FGF-2 species of 18 kilodaltons (kDa), although this was not present in nonpregnant serum. In AGA pregnancies, immunoreactive FGF-2 was present in MS from at least 18 weeks gestation and rose to maximum values at the end of second trimester (weeks 28-31; mean +/- SEM, 342 +/- 62 pmol/L), but by term had declined (weeks 40-42; 104 +/- 24 pmol/L). In CS, FGF-2 immunoreactivity was highest at weeks 18-20 of gestation (662 +/- 144 pmol/L), but thereafter, slowly declined to term (weeks 40-42; 119 +/- 28 pmol/L). Immunoreactive FGF-2 levels in MS and CS of small for gestational age pregnancies in the second trimester tended to be lower than those in AGA pregnancies, but differences were not statistically significant. AF also contained immunoreactive FGF-2 at term (91 +/- 35 pmol/L). Neutral gel chromatography on Sephadex G-200 revealed that FGF-2 immunoreactivity eluted as a broad peak with an apparent molecular size of 55-160 kDa. These same fractions contained peptides of 55-60, 90-95, and 120-130 kDa, which were recognized by antisera against the extracellular domain of the high affinity FGF receptor, FGFR1, after Western blot. Ligand blot analysis of the same nitrocellulose filters using 125I-labeled FGF-2 revealed that the 55- to 60-kDa species specifically bound FGF-2. This binding species was not recognized during Western blot analysis using an antiserum raised against the intracellular tyrosine kinase domain of FGFR1, suggesting that it represents a truncated receptor form. Similar FGFR1 immunoreactive species were present in nonpregnant female and male sera, but were barely detectable in term CS or AF.(ABSTRACT TRUNCATED AT 400 WORDS)
成纤维细胞生长因子-2（FGF-2）在人类胎儿组织和胎盘中表达。因此，我们确定了在正常妊娠[适于胎龄（AGA）的胎儿]或合并胎儿生长受限（小于胎龄）的妊娠中，FGF-2是否会出现在胎儿或母体循环中。进行了脐血穿刺术，并在妊娠19至39周期间采集了配对的母体血液，而在足月时采集了母体血、脐血和羊水（AF）。通过肝素-琼脂糖亲和层析从母体血清（MS）、脐血血清（CS）和羊水中提取FGF-2，并进行蛋白质印迹分析或通过特异性放射免疫分析进行定量。对MS、CS和AF的蛋白质印迹分析显示，在每种情况下，均有一条18千道尔顿（kDa）的单一免疫反应性FGF-2条带，尽管在非妊娠血清中不存在。在AGA妊娠中，至少从妊娠18周起，MS中就存在免疫反应性FGF-2，并在妊娠中期结束时（第28 - 31周；平均值±标准误，342±62 pmol/L）升至最高值，但到足月时有所下降（第40 - 42周；104±24 pmol/L）。在CS中，FGF-2免疫反应性在妊娠18 - 20周时最高（662±144 pmol/L），但此后缓慢下降至足月（第40 - 42周；119±28 pmol/L）。小于胎龄妊娠中期MS和CS中的免疫反应性FGF-2水平往往低于AGA妊娠，但差异无统计学意义。足月时AF中也含有免疫反应性FGF-2（91±35 pmol/L）。在Sephadex G - 200上进行中性凝胶层析显示，FGF-2免疫反应性以一个宽峰形式洗脱，表观分子大小为55 - 160 kDa。这些相同的组分含有55 - 60 kDa、90 - 95 kDa和120 - 130 kDa的肽段，在蛋白质印迹后，这些肽段可被抗高亲和力FGF受体FGFR1细胞外结构域的抗血清识别。使用125I标记的FGF-2对相同的硝酸纤维素滤膜进行配体印迹分析显示，55至60 kDa的条带特异性结合FGF-2。在使用针对FGFR1细胞内酪氨酸激酶结构域产生的抗血清进行蛋白质印迹分析时，这种结合条带未被识别，表明它代表一种截短的受体形式。在非妊娠女性和男性血清中也存在类似的FGFR1免疫反应性条带，但在足月CS或AF中几乎检测不到。（摘要截断于400字）
