Developmental alterations in the alpha-fetoprotein sugar chain in maternalserum analyzed by lectin affinity electrophoresis

Our purpose was to investigate developmental alterations of human a-fetopro tein (AFP) oligosaccharides in maternal serum by lectin affinity electropho resis and to compare the AFP glycoforms in maternal serum with those in umb ilical cord serum and amniotic fluid. AFP glycoforms were separated by affi nity electrophoresis with concanavalin A (Con A), lentil lectin (LCA), eryt hroagglutinating phytohemagglutinin (E-PHA) and Allomyrina dichotoma lectin (allo A) and detected by sensitive antibody affinity blotting. In maternal serum, increased proportions of Con A-nonreactive AFP (AFP-C1), LCA strong ly-reactive AFP (AFP-L3) and E-PHA-reactive AFP (AFP-P4 and AFP-P5) decreas ed gradually during the early gestational weeks. Allo A-nonreactive AFP (AF P-A1 and asialo-AFP) were found only in amniotic fluids during early gestat ional weeks. The percentages of these glycoforms at full term were almost t he same among those body fluids. Since the glycoforms of maternal serum AFP were close to those of umbilical cord serum AFP, lectin-affinity electroph oretic analysis of maternal serum AFP may be useful for evaluating the deve lopmental state of fetus by examining the nature of AFP sugar chain.