Distribution of SP1, immunoreactivity among different plasma proteins: real molecular heterogeneity or adsorption of SP1-beta to other plasma proteins?

Rapid purification and properties of human glycodelin (endometrial alpha2-globulin)

The method presented can easily produce milligram amounts of glycodelin from pregnancy endometrium, with a 19% yield. It involves anion-exchange chromatography, gel permeation and chromatofocusing; it results in one stainable band at Mr 28,000 after sodium dodecyl sulphate-polyacrylamide electrophoresis, as well as after immunoblot analysis, performed using an affinity-purified IgG fraction from an antiserum against glycodelin. In spite of this, the corresponding gel isoelectric focusing pattern gives four stainable bands with pI values between 4.55 and 5.2. Western immunoblot analysis of tissue extracts indicates the presence of glycodelin epitopes associated with materials heavier than the native protein. Circular dichroism spectra of the highly purified protein in water solutions indicate a large amount of beta-sheet conformation, whereas those obtained with different proportions of 2-propanol in water, show an increased proportion of alpha-helix conformation.

Pregnancy specific beta 1 glycoprotein (SP-1) in maternal serum and amniotic fluid; pre-eclampsia, small for gestational age fetus and fetal distress

Pregnancy specific beta 1 glycoprotein (SP-1) levels have been suggested to correlate with certain obstetrical complications. We compared maternal serum SP-1 levels in normal pregnancies (N = 82), and pregnancies complicated by pre-eclampsia (N = 37), small for gestational age fetuses (N = 8) and fetal distress (N = 13). We also compared levels of this protein in mid-trimester amniotic fluid samples obtained from normal (N = 47) and small for gestational age fetuses (N = 25). Despite trends towards low maternal serum and amniotic fluid SP-1 values in complicated pregnancies, there were no statistically significant differences in their levels as compared with normal gestational age matched controls (P > 0.05). These data do not support the use of SP-1 values in clinical practice.