Human trophoblast stem cells cultured for first time

Scientists in Japan have cultured human trophoblast stem cells, which form the placenta, for the first time.

'Trophoblast cells play an essential role in the interactions between the fetus and mother,' said study author Professor Takahiro Arima of Tohoku University School of Medicine, Japan. The research was published in Cell Stem Cell.

The placenta originates from trophoblast cells. If the growth of these cells is impaired, it can lead to placenta-based pregnancy complications, such as preeclampsia. The placenta provides oxygen and nutrients for the fetus and removes waste products. One in ten pregnancies have placenta-based complications.

Without a human stem cell model, these cells have been difficult to study. In the new study, the team moved towards a model, by first using genetic sequencing on trophoblast cells from human placenta to discover how the cells are maintained in the body. They found a combination of genes that were either activated or inactivated, and mimicked this to keep the cells alive in a dish.

In addition, the team could differentiate the trophoblast stem cells into different trophoblast cell types but further research is needed to fully test their potential, it said.

Other models of human trophoblast cells have been made previously, but according to the scientists, these cells have a different protein expression compared with native trophoblast cells.

'Our goal was to establish human trophoblast stem cells [as a tool for future study],' said Professor Arima. The human trophoblast stem cell line could provide a platform for studying placental disease and potentially for discovering diagnostic biomarkers and therapeutic targets for common pregnancy complications.

The new culture system will provide a powerful tool to study human trophoblast development and function, the researchers said. 'Our culture system for human trophoblast stem cells is potentially useful for understanding the pathogenesis of developmental disorders with trophoblast defects, such as miscarriage, preeclampsia and intrauterine growth restriction,' said Professor Arima.