Immunohistological localization of human pregnancy-associated endometrial alpha 2-globulin (alpha 2-PEG), a glycosylated beta-lactoglobulin homologue, in the decidua and placenta during pregnancy.
Monoclonal and polyclonal antibodies to pregnancy-associated endometrial alpha 2-globulin (alpha 2-PEG), a glycosylated human beta-lactoglobulin homologue, were used in an immunohistological technique to determine the cellular localization of this protein in the decidua and placental tissues during pregnancy. During the first trimester the protein was principally localized to the glandular epithelium of the decidua spongiosa region of the endometrium with only weak staining associated with glands of the decidualized decidua compacta region. No significant cellular staining was detected in the decidua capsularis. At term in the decidua of the amniochorion and the placental bed weak staining for alpha 2-PEG was only associated with the epithelium of attenuated glands. No significant staining was detected in the placenta during pregnancy. These results suggest that the epithelium of glands associated with non-decidualized stroma represents the primary source of alpha 2-PEG during the first trimester and that a function of the decidua spongiosa in early pregnancy may be related to production of alpha 2-PEG. The decline in production of alpha 2-PEG during pregnancy is suggested to result from involution of the decidua spongiosa and at term the attenuated glands of the decidua represents the source of alpha 2-PEG.
Waites
G T
GT
Department of Obstetrics & Gynaecology, University of Leicester, UK.
Bell
S C
SC
D003656:Decidua / Q000032:analysis*; D004848:Epithelium / Q000032:analysis; D005260:Female; D000071816:Glycodelin; D006023:Glycoproteins; D006801:Humans; D007124:Immunoenzyme Techniques; D010920:Placenta / Q000032:analysis*; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000032:analysis*
D000071816:Glycodelin; D006023:Glycoproteins; C045246:PAEP protein, human; D011257:Pregnancy Proteins