Head of Laboratory

David Simmons


MacGregor Building (#64), Room 415



  • Joanna Rakoczy, PhD student
  • Jennifer Outhwaite, Honours student
  • Muhammad Nadzim Bin Ramli, Honours student
  • Thu Aung Zin, Honours student


The major focus of our lab is development of the placenta; a highly specialized organ of pregnancy that facilitates the exchange of nutrients and waste between a mother and her developing fetus (or fetuses if you happen to be a mouse). Abnormalities in placentation can result in a range of serious pregnancy complications such as pre-eclampsia and intrauterine growth restriction (IUGR).

Our lab uses transgenic mouse lines, trophoblast stem cell cultures, and other molecular biology tools to study placental development and early implantation in mice.

More specifically, the lab has an interest in the differentiation and function of trophoblast cells, the cell type that makes up the majority of the mature placenta. Trophoblast cells are a diverse bunch, with distinct subtypes having unique cell biology and roles within the placenta; some trophoblast cells are multinucleated as a result a cell-cell fusion (syncytiotrophoblast), some are invasive (glycogen trophoblast cells), while others become enormous polyploid cells due to an unusual cell cycle called endoreduplication. Collectively, we are interested in how these different trophoblast subtypes differentiate from stem cells and how they interact to form a functional placenta.

Along with placental development, the lab also has an interest in the initiation of embryo implantation. We aim to understand more about the uterine environment into which embryos implant and how changes to this environment are regulated and affect fertility.

Recent Publications

For a full list of publications see Simmons DG Researcher ID: C-5983-2009

  1. Dawson PA, Rakoczy J, Simmons DG (2012). Placental, renal, and ileal sulfate transporter gene expression in mouse gestation. Biol Reprod. Aug 23; 87(2): 43.
  2. Dawson PA, Sim P, Simmons DG, Markovich D. (2011) Fetal loss and hyposulfataemia in pregnant NaS1 transporter null mice. J Reprod Dev. Sep; 57(4): 444-9.
  3. Simmons DG, Natale DR, Begay V, Hughes M, Leutz A, Cross JC (2008) Early patterning of the chorion leads to the trilaminar trophoblast cell structure in the placental labyrinth. Development. Jun; 135(12): 2083-91.
  4. Simmons DG, Fortier AL, Cross JC (2007) Diverse subtypes and developmental origins of trophoblast giant cells in the mouse placenta. Developmental Biology. Apr 15; 304(2): 567-78.
  5. Simmons DG and Cross JC (2005) Determinants of trophoblast lineage and cell subtype specification in the mouse placenta. Developmental Biology. Aug 1; 284(1): 12-24. Review.

Student projects


1. The role of histone variants and chromatin remodeling in preparing the endometrium for embryo implantation and early placental development
2. Characterization the placental phenotype of Ly6e-/- mice
3. Investigating an unusual placental cell-type - sinusoidal trophoblast giant cells


The role of sulfate in maternal adaptations to pregnancy: brain development and mothering ability.