Shawn L Straszewski-Chavez

Learn More
Intrauterine infections have been associated with pregnancy complications that are also linked with increased trophoblast apoptosis. TLRs are key components of the innate immune system which recognize conserved sequences on the surface of pathogens and trigger effector cell functions. We hypothesize that intrauterine infections may cause the excessive(More)
Apoptosis is important for normal placental development, but it may also be involved in the pathophysiology of pregnancy-related diseases. Normal placental development is dependent upon the differentiation and invasion of the trophoblast, the main cellular component of the placenta. Trophoblast apoptosis increases in normal placentas as gestation proceeds,(More)
Since the invading trophoblast represents a semi-allograft, it should be rejected by the mother. It has, therefore, been postulated that during normal pregnancy the trophoblast evades the maternal immune system though the establishment of immune privilege by triggering the death of activated lymphocytes which may be sensitized to paternal alloantigens. Such(More)
Challenge lies ahead in unravelling the role played by trophoblast and its repertoire of expressed genes in normal human placental development, growth and pathology. Specific technical advances will clearly be required for characterisation of function. In particular, improvements in our repertoire of in vitro models are needed before many of the key(More)
Studies using first trimester trophoblast cells may be limited by the inability to obtain patient samples and/or adequate cell numbers. First trimester trophoblast cell lines have been generated by SV40 transformation or similar methods, however, this approach is known to induce phenotypic and karyotypic abnormalities. The introduction of telomerase has(More)
Apoptosis occurs in the placenta throughout gestation, with a greater frequency near term in comparison to the first trimester. The Fas/FasL system represents one of the main apoptotic pathways controlling placental apoptosis. Although first trimester trophoblast cells express both Fas and FasL, they are resistant to Fas-induced apoptosis. Therefore,(More)
During implantation and pregnancy, the invading trophoblast population is within close contact to maternal immune cells, particularly macrophages. During this period, a low level of trophoblast cell death occurs as part of the normal process of tissue renewal. Macrophage engulfment of apoptotic trophoblast cells prevents the release of potentially(More)
Tumor necrosis factor-alpha (TNF-alpha) and Fas ligand induce apoptosis by interacting with their corresponding membrane-bound death receptors and activating caspases. Since both systems share several components of the intracellular apoptotic cascade and are expressed by first trimester trophoblasts, it is unknown how these cells remain resistant to Fas(More)
Increased trophoblast apoptosis has been implicated in pregnancies complicated by fetal growth restriction and preeclampsia (EC). We investigated placenta growth factor (PLGF) signaling during trophoblast apoptosis in culture and X-linked inhibitor of apoptosis protein (XIAP) and apoptosis inducible factor (AIF) in the preeclamptic placenta at term was(More)
The PIK3/AKT pathway plays an important role in both the inhibition of the apoptotic cascade and the promotion of cell growth and proliferation. Multiple apoptosis-related targets of phosphatidylinositide 3-kinase (PIK3) and protein kinase B (AKT) have been identified, including the antiapoptotic protein XIAP. By phosphorylating XIAP, AKT was previously(More)
  • 1