Concanavalin A binding of alpha-fetoprotein in amniotic fluid as an aid in the diagnosis of neural tube defects.

1981 ◽  
Vol 27 (10) ◽  
pp. 1658-1660 ◽  
Author(s):  
P K Buamah ◽  
P Taylor ◽  
A M Ward
Keyword(s):  
Spina Bifida ◽  
Amniotic Fluid ◽  
Neural Tube ◽  
Neural Tube Defects ◽  
Concanavalin A ◽  
Gestational Age ◽  
Alpha Fetoprotein ◽  
Normal Outcome ◽  
Fetal Malformations ◽  
Open Spina Bifida

Abstract Concanavalin A nonreactive alpha-fetoprotein was determined in samples of amniotic fluid from 16 abnormal pregnancies complicated by anencephaly (7), open spina bifida (6), intra-uterine death (1), anencephaly with exomphalos (1), or open spina bifida with exomphalos (1), and in amniotic fluid from 50 normal pregnancies with gestational age between 13 and 24 weeks. In all 16 cases with fetal malformations, the proportion of nonreactive alpha-fetoprotein was significantly decreased (median 5.3%) as compared with amniotic fluid from pregnancies with a normal outcome (median 39.7%). The results confirm that this measurement is useful in the diagnosis of neural tube defects, especially when the concentration of alpha-fetoprotein in amniotic fluid is normal or only slightly above normal and gestational age is uncertain.

Acetylcholinesterase and fetal malformations: modified qualitative technique for diagnosis of neural tube defects.

1981 ◽  
Vol 27 (1) ◽  
pp. 61-63 ◽  
Author(s):  
J E Haddow ◽  
M E Morin ◽  
M S Holman ◽  
W A Miller
Keyword(s):  
Amniotic Fluid ◽  
Neural Tube ◽  
Neural Tube Defects ◽  
False Positive ◽  
Alpha Fetoprotein ◽  
Blind Study ◽  
Fetal Malformations ◽  
Qualitative Technique ◽  
Single Blind ◽  
Positive Results

Abstract A single-blind study involving amniotic-fluid samples from 214 pregnancies of known outcome confirms that an electrophoretically distinct isoenzyme of acetylcholinesterase is associated with fetal open neural tube defects. Furthermore, only one of 13 amniotic-fluid samples with false-positive results for alpha-fetoprotein showed the characteristic isoenzyme, indicating that qualitative acetylcholinesterase assessment can decrease the proportion of false positives from the alpha-fetoprotein assay. We have also identified this characteristic isoenzyme in amniotic fluids from pregnancies in which other serious fetal defects occurred. A detailed electrophoresis protocol for identifying this characteristic isoenzyme is described.

Reactivity of amniotic fluid alpha-fetoprotein with concanavalin A in relation to gestational age: clinical implications.

1980 ◽  
Vol 26 (12) ◽  
pp. 1656-1659 ◽  
Author(s):  
K Toftager-Larsen ◽  
E Kjaersgaard ◽  
J C Jacobsen ◽  
B Nørgaard-Pedersen
Keyword(s):  
Amniotic Fluid ◽  
Clinical Significance ◽  
Concanavalin A ◽  
Gestational Age ◽  
Normal Values ◽  
Alpha Fetoprotein ◽  
Clinical Implications ◽  
Fetal Malformation ◽  
Average Decrease ◽  
Normal Outcome

Abstract We used concanavalin A crossed-line affinity immunoelectrophoresis to determine the percentage of concanavalin A nonreactive alpha-fetoprotein in amniotic fluid samples from pregnancies with normal and abnormal fetuses. In 167 samples from pregnancies with a normal outcome and normal values for total alpha-fetoprotein concentration in amniotic fluid the percentage decreased from a median value of 27.4% in the 13th week to 8.5% in the 21st week of gestation, and a statistically significant (p < 0.001) average decrease of 1.7% per week was found from the 14th to the 19th week. A similar average decrease (2.2%) was found in 22 pregnancies from which two or more samples were obtained. The clinical significance of this decrease is discussed. Of 108 samples from patients with above-normal values for total alpha-fetoprotein and a normal outcome, seven had a total alpha-fetoprotein above recommended cut-off values, and only one of these had a low percentage of concanavalin A nonreactive alpha-fetoprotein. In contrast, for all 27 samples from pregnancies with a severe fetal malformation this percentage was low, even in one case where the total alpha-fetoprotein concentration was below the recommended cut-off value.

CONCANAVALIN-A REACTIVITY OF AMNIOTIC FLUID ALPHA-FETOPROTEIN IN DIAGNOSIS OF NEURAL-TUBE DEFECTS

The Lancet ◽  
1979 ◽  
Vol 314 (8148) ◽  
pp. 906 ◽  
Author(s):  
P. Hindersson ◽  
K. Toftager-Larsen ◽  
B. Nørgaard-Pedersen
Keyword(s):  
Amniotic Fluid ◽  
Neural Tube ◽  
Neural Tube Defects ◽  
Concanavalin A ◽  
Alpha Fetoprotein

scholarly journals Affinity Chromatography of Amniotic Fluid Alphafetoprotein Using Concanavalin A-Sepharose

1981 ◽  
Vol 18 (6) ◽  
pp. 350-352 ◽  
Author(s):  
Jennifer A Noyes ◽  
P J Wood
Keyword(s):  
Spina Bifida ◽  
Amniotic Fluid ◽  
Neural Tube ◽  
Neural Tube Defect ◽  
Concanavalin A ◽  
Con A ◽  
Potential Value ◽  
Significant Difference ◽  
Normal Outcome ◽  
Chromatography Columns

We measured Concanavalin A (Con A) non-binding alphafetoprotein in amniotic fluid from 21 normal pregnancies and 20 abnormal pregnancies (complicated by anencephaly, spina bifida, or exomphalos) using small Con A-sepharose chromatography columns. There was a highly significant difference between percentage non-binding alphafetoprotein levels for pregnancies with a normal outcome (mean result 32%; range 18–47%) and pregnancies complicated by a neural tube defect or exomphalos (mean 14%; range 7–20%). The test is therefore of potential value in cases where there is uncertainty over the interpretation of total amniotic fluid alphafetoprotein levels.

Comparison of amniotic fluid alpha-fetoprotein reactivity to Lens culinaris agglutinin and concanavalin A in crossed-affinity immunoelectrophoresis: ancillary tests in the prenatal diagnosis of severe fetal malformations.

1983 ◽  
Vol 29 (1) ◽  
pp. 21-24 ◽  
Author(s):  
K Toftager-Larsen ◽  
E Kjaersgaard ◽  
B Nørgaard-Pedersen
Keyword(s):  
Prenatal Diagnosis ◽  
Amniotic Fluid ◽  
Neural Tube ◽  
Neural Tube Defects ◽  
Concanavalin A ◽  
Lens Culinaris ◽  
Alpha Fetoprotein ◽  
Fetal Abnormality ◽  
Lens Culinaris Agglutinin ◽  
Ancillary Test

Abstract Crossed-affinity immunoelectrophoresis of alpha-fetoprotein in amniotic fluid from 135 normal and 39 abnormal pregnancies (mainly neural-tube defects) was performed with a lectin, agglutinin from Lens culinaris. Results were compared with findings reported for another lectin, concanavalin A. Three fractions of alpha-fetoprotein were obtained by reaction with Lens culinaris agglutinin. The most weakly reactive fraction correlated strongly with the concanavalin A nonreactive fraction. With both lectins, significantly lower concentrations of these fractions were found in all samples from abnormal pregnancies than in those from normal pregnancies. In eight cases with a fetal abnormality the total alpha-fetoprotein concentrations were below the lower limit for abnormal samples. All eight samples revealed fractions weakly reactive with Lens culinaris agglutinin below the lower 0.1% limit for normal samples; seven of these samples had fractions nonreactive with concanavalin A below this limit. Although a decrease in the two described fractions in normal pregnancies was found with increasing gestational age, we find either method to be valuable as an ancillary test in the prenatal diagnosis of fetal neural-tube defects and other malformations.

The Impact of Gestational Age on Targeted Amniotic Cell Profiling in Experimental Neural Tube Defects

2014 ◽  
Vol 37 (1) ◽  
pp. 65-69 ◽  
Author(s):  
Elliot C. Pennington ◽  
Kristy L. Rialon ◽  
Beatrice Dionigi ◽  
Azra Ahmed ◽  
David Zurakowski ◽  
...  
Keyword(s):  
Stem Cells ◽  
Spina Bifida ◽  
Amniotic Fluid ◽  
Neural Tube ◽  
Neural Tube Defects ◽  
Gestational Age ◽  
Sprague Dawley ◽  
Amniotic Cell ◽  
The Impact ◽  
Wallis Anova

Purpose: The proportions of select stem cells in term amniotic fluid have been shown to correlate with the type and size of experimental neural tube defects (NTDs). We sought to determine the impact of gestational age upon this form of targeted amniotic cell profiling. Methods: Sprague-Dawley fetuses with retinoic acid-induced NTDs (n = 110) underwent amniotic fluid procurement at four time points in gestation. Samples were analyzed by flow cytometry for the presence of cells concomitantly expressing Nestin and Sox-2 (neural stem cells, aNSCs) and cells concomitantly expressing CD29 and CD44 (mesenchymal stem cells, aMSCs). Statistical analysis was by nonparametric Kruskal-Wallis ANOVA (p < 0.05). Results: There was a statistically significant impact of gestational age on the proportions of both aMSCs (p = 0.01) and aNSCs (p < 0.01) in fetuses with isolated spina bifida. No such impact was noted in normal fetuses (p > 0.10 for both cells), in isolated exencephaly (p > 0.10 for both cells), or in combination defects (p > 0.10 for both cells). Gestational age had no effect on aNSC/aMSC ratios. Conclusions: Targeted quantitative amniotic cell profiling varies with gestational age in experimental isolated spina bifida. This finding should be considered prior to the eventual translation of this diagnostic adjunct into the prenatal evaluation of these anomalies.

scholarly journals Neurone Specific Enolase in Amniotic Fluid: A Potential Marker of Anencephaly

1988 ◽  
Vol 25 (1) ◽  
pp. 85-88 ◽  
Author(s):  
K Spencer ◽  
P Carpenter
Keyword(s):  
Prenatal Diagnosis ◽  
Spina Bifida ◽  
Amniotic Fluid ◽  
Neural Tube ◽  
Neural Tube Defects ◽  
Normal Values ◽  
Potential Marker ◽  
Neuronal Proteins ◽  
Non Gaussian ◽  
Open Spina Bifida

Normal values for neurone specific enolase in amniotic fluid have been found to follow a non gaussian distribution with a 1–99 centile range of 1·10–4·32 μg/L. Neurone specific enolase levels have been shown to be raised in the amniotic fluid of pregnancies complicated by anencephaly, although not those complicated by open spina bifida. Neurone specific enolase measured by radioimmunoassay is capable of totally discriminating between normal pregnancies and those complicated by anencephaly. The study demonstrates the possible value of investigating other neuronal proteins which may find value as adjuncts to amniotic fluid Alpha fetoprotein levels in the prenatal diagnosis of Neural Tube Defects.

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