Spatiotemporal Expression of C-CAM in the Rat Placenta

Abstract

We investigated the expression of the immunoglobulin superfamily cell adhesion molecule, C-CAM, in developing and mature rat placenta. By immunohistochemical staining at the light microscopic level, no C-CAM-expression was seen before Day 9 of gestation, when it appeared in the trophoblasts of ectoplacental cones. On Day 10.5, spongiotrophoblasts and invasive trophoblasts around the maternal vessels of the decidua basalis were stained positively. On Day 12.5, C-CAM was detected in the spongiotrophoblasts of the junctional layer, but labyrinth trophoblasts and secondary giant trophoblasts were not stained. On Day 17.5, C-CAM was found only in the labyrinth and lacunae of the junctional layer. At this stage, both the labyrinth cytotrophoblasts of the maternal blood vessels and the endothelial cells of the embryonic capillaries were strongly stained. Placental tissues from gestational Days 12.5 and 17.5 were analyzed by immunoelectron microscopy to determine the location of C-CAM at the subcellular level. On Day 12.5, positive staining of the spongiotrophoblasts was observed, mainly on surface membranes and microvilli between loosely associated cells. On Day 17.5, staining was found primarily on the microvilli of the maternal luminal surfaces of the labyrinth cytotrophoblasts, and both on the luminal surface and in the cytoplasm of endothelial cells of the embryonic vessels. RT-PCR analysis and Southern blotting of the PCR products revealed expression of mRNA species for both of the major isoforms, C-CAM1 and C-CAM2. Immunoblotting analysis of C-CAM isolated from 12.5-day and 14.5-day placentae showed that it appeared as a broad band with an apparent molecular mass of 110–170 kD. In summary, C-CAM was strongly expressed in a specific spatiotemporal pattern in trophoblasts actively involved in formation of the placental tissue, suggesting an important role in placental development. In the mature placenta, C-CAM expression was confined to the trophoblastic and endothelial cells lining the maternal and embryonic vessels, respectively, suggesting important functions in placental physiology.

CEA adhesion molecules: multifunctional proteins with signal-regulatory properties

“…In adult tissues the CEA-related cell surface molecules are expressed primarily in different epithelia, vessel endothelia, and hematopoietic cells [11][12][13][14][15], but individual molecules show distinct expression patterns. The spatiotemporal expression pattern of C-CAMs suggests important functions during embryonic development; a highly dynamic expression has been seen in, for example, the trophoblasts of the placenta [16,17], the endothelial cells and pericytes during vascularization of the central nervous system [18], muscle development [16], and development and eruption of teeth [19].…”

CEACAM1 structure and function in immunity and its therapeutic implications

“…Its initial discovery was as a biliary glycoprotein that is present in the bile in association with expression on the hepatocyte membrane [2][3][4]. CEACAM1 expression occurs as early as embryonic development where it is found on trophoblasts of both the pre-implanting embryo, placenta and infiltrating leukocytes [5][6][7]. CEACAM1 also exhibits either constitutive (e.g.…”

Carcinoembryonic antigen-related cell adhesion molecule 1 modulates vascular remodeling in vitro and in vivo

“…We and others reported that the IgSF molecule carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is associated with early stages of angiogenesis: CEACAM1 is expressed in newly formed blood vessels on the fetal-maternal interface in both rodents and humans; on microvessels of a variety of human tumors and of regenerating tissues, such as endometrium or granuloma tissue after wounding; on endothelial progenitor cells; and in stenotic aortic valve tissue (12)(13)(14)(15)(16). Notably, CEACAM1 exhibits a disease-specific expression pattern on tumoral endothelium in vivo, as demonstrated by Oh et al (17), and appears to be involved in vascular reprogramming in Kaposi sarcoma (18).…”