Targeting the placenta

When a pregnant woman’s placenta malfunctions, such as in life-threatening preeclampsia, doctors are often forced to deliver a baby prematurely to avoid further harm to the mother or the fetus. Few companies have pursued treatments that could alleviate or cure placental disease, in part because of concerns that the drug could harm a developing baby. But what if researchers could develop a way to deliver drugs only to the placenta? A team of researchers led by the University of Manchester’s Lynda K. Harris has tackled this challenge. Noting that certain placenta cells possess the same surface proteins as solid tumor cells, the scientists suspected that they could use peptides that target tumors to perform a different job—deliver treatment cargoes to the placenta. Working with mice, the team showed that they could deliver cargoes of insulin-like growth-factor 2 to a rodent placenta, which increased the weight of the placenta and the fetus and did not harm the fetus (Sci. Adv. 2016, DOI: 10.1126/sciadv.1600349). If the results hold true for humans, the strategy could pave the way for the development of drugs for otherwise untreatable, life-threatening diseases in pregnant women.