Feinberg R F, Wang C L
Department of Obstetrics and Gynecology, University of Pennsylvania Medical Center, Philadelphia 19104-4283.
Am J Obstet Gynecol. 1994 Nov;171(5):1302-8. doi: 10.1016/0002-9378(94)90152-x.
Monoclonal antibody FDC-6 has been used clinically to measure cervicovaginal fibronectin and to predict patients at risk for preterm labor. Because bleeding is often a complicating factor during pregnancy, the aim of this study was to determine whether FDC-6 reactive fibronectin is present in normal human plasma.
Quantitative Western immunoblots and a commercially available enzyme-linked immunosorbent assay were used to measure FDC-6 binding to nonpregnant human and bovine plasma fibronectin. FDC-6 binding to whole sera was also assessed, as was the effect of enzymatic deglycosylation of human plasma fibronectin.
Both assays demonstrated measurable FDC-6-reactive fibronectin in nonpregnant human blood, with plasma concentrations ranging from 3 to 12 micrograms/ml (1% to 4% of total plasma fibronectin). FDC-6 had no detectable binding activity to bovine plasma fibronectin. De-O-glycosylated human plasma fibronectin had markedly reduced binding activity for FDC-6.
FDC-6 binds specifically to a clinically significant percentage of circulating O-glycosylated human plasma fibronectin isoforms that are not associated with pregnancy. This caveat should be considered when pregnant patients are evaluated for the presence of FDC-6 reactive oncofetal fibronectin in the cervix or vagina.
单克隆抗体FDC - 6已在临床上用于检测宫颈阴道纤连蛋白，并预测早产风险患者。由于出血在孕期常常是一个复杂因素，本研究的目的是确定正常人血浆中是否存在FDC - 6反应性纤连蛋白。
采用定量蛋白质免疫印迹法和一种市售的酶联免疫吸附测定法来检测FDC - 6与非孕人血浆及牛血浆纤连蛋白的结合情况。还评估了FDC - 6与全血清的结合情况，以及人血浆纤连蛋白酶促去糖基化的影响。
两种检测方法均显示在非孕人血液中可检测到FDC - 6反应性纤连蛋白，血浆浓度范围为3至12微克/毫升（占血浆总纤连蛋白的1%至4%）。FDC - 6对牛血浆纤连蛋白无可检测的结合活性。去O - 糖基化的人血浆纤连蛋白对FDC - 6的结合活性显著降低。
FDC - 6特异性结合临床上显著比例的循环O - 糖基化人血浆纤连蛋白异构体，这些异构体与妊娠无关。在评估妊娠患者宫颈或阴道中是否存在FDC - 6反应性癌胚纤连蛋白时应考虑这一注意事项。
