concanavalin-a and Pregnancy--Prolonged

Alterations in the AGP glycoform pattern are not only disease related, but also can occur during physiological processes such as pregnancy. In this paper, possible changes in human amniotic fluid AGP glycan branching and in the type of sialic acid glycosidic attachment to glycans were analyzed with regard to different stages of human pregnancy.. Crossed-affinity immunoelectrophoresis with concanavalin A was used to study AGP branching and lectin-ELISA with two agglutinins from Maackia amurensis and Sambucus nigra was applied to differentiate alpha2,3 and alpha2,6 type sialic acid attachments.. Despite almost unchanged levels of total amniotic fluid AGP during pregnancy, alterations in N-glycan branching and in the expression of sialic acid linkage on AGP were found to be associated with different stages of normal pregnancy. Amniotic fluid AGP glycans derived from third trimester compared with those from the second trimester had a higher percentage of tri- and tetra-antennary sialylated N-glycans. In the second trimester, sialic acid alpha2,6 linkage occurred twice as frequently as alpha2,3 linkage, while during the third trimester alpha2,3 linkage increased and both types of linkage appeared in equal proportion.. Branched and alpha2,3-sialylated AGP glycoforms in amniotic fluid could contribute to natural innate fetomaternal defense.

Topics: Amniotic Fluid; Concanavalin A; Female; Gene Expression Regulation; Humans; N-Acetylneuraminic Acid; Orosomucoid; Polysaccharides; Pregnancy; Pregnancy Trimester, Second; Pregnancy Trimester, Third; Pregnancy, Prolonged