PREGNANCY SPECIFIC BETA‐1 GLYCOPROTEIN (SP1) IN PATIENTS WITH TROPHOBLASTIC DISEASE: MOLECULAR HETEROGENEITY AND A »SP1 CONSUMING FACTOR«

The reactivity of sera from 19 patients with trophoblastic disease was analyzed in analytic immunoelectrophoresis using rabbit anti human pregnancy specific beta-1 glycoprotein (SP1) antisera. Molecular heterogeneity of SP1 was demonstrated in crossed immunoelectrophoresis and a »SP1 consuming factors« was found in serum from a patient with choriocarcinoma. The »SP1 consuming factor« was precipitated by 1.65 M (NH4)2SO4. The results are discussed in relation to quantification of circulating SP1 in patients with trophoblastic disease.