Metalloprotease Dependent Release of Placenta Derived Fractalkine
Figure 1
Immunohistochemical localization of fractalkine in human placenta. In first trimester placental villi fractalkine was only detected at the apical microvillous plasma membrane of the syncytiotrophoblast ((a) and (b), black arrow), but not in the fetal endothelium ((a), arrowheads), villous cytotrophoblasts ((a) and (b), open arrows), and extravillous trophoblasts in cell columns ((b), asterisk). In first trimester decidua fractalkine was detected at the apical plasma membrane of uterine glandular epithelial cells ((c) and (d), open arrows), whereas spiral arteries ((c), arrowheads) and veins ((d), open arrowheads) did not show any staining. In term placenta fractalkine was detected at the apical plasma membrane of the syncytiotrophoblast ((e) and (f), black arrows). The fetal vascular endothelium of all villous types including terminal villi ((e), arrowheads) and stem villi ((f), arrowhead) did not express fractalkine. Specificity of the antibody was evaluated on serial first trimester placenta sections using an antibody preadsorption approach and negative control mouse IgG, respectively. While incubation with the antibody alone confirmed the above described staining pattern (g), preadsorption of the antibody with recombinant fractalkine almost completely abolished staining (h). Incubation with negative control mouse IgG revealed no staining (i). Scale bar represents 50 μm.
