An article by the American Chemical Society dated December 4, 2017, has highlighted the possibility of targeted delivery of drugs to cancer tissues using sperm robots (spermbots). Research is still ongoing, but recent findings using bovine sperm has shown some promising results. Researchers from the Leibniz Institute for Solid State and Materials Research in Dresden, Germany reportedly transformed bovine sperm into torpedos and released them on a tumor-like mass in a petri dish.
The bovine sperm cells numbering about 3,500 were doused with doxorubicin hydrochloride, an anticancer drug absorbable by the sperm cells. According to Mariana Medina-Sanchez, one of the members of the research team, 98 percent of the sperm cells absorbed the drug mostly in the cytoplasm and nucleus in their heads.
Using nanotechnology, the sperm cells were covered with 3D-printed armor made out of titanium and iron. These “micromotors” are built with four flexible arms and a microscopic tube, the arms act as a gate to keep the doused sperm cells in place until they are ready to attack the cancer cells.
The researchers then use weak magnetic fields to guide the armored sperm to the woman’s cervical cancer tissue. Once the spermbots reach the tumor-like mass, the sperm’s armor opens and the sperm swims into the tumor. The findings indicate that these sperms killed 87 percent of the cancer cells over a period of 72 hours. A second petri dish with a similar tumor-like mass infused with the same dose of the drug killed only 55 percent of the cancer cells over the same 72 hour period.
The spermbots were more efficient because the drug was delivered directly into the cells while just applying the drug to the petri dish only reached the outer layer of the cancer cells.
Sperms cells were used because they can fuse with eggs and non-reproductive cells making them fit to absorb and deliver drugs to targeted cells. Sperm is unaffected by doxorubicin and their short lifespan protects them from the drug’s effects.
However, there are concerns that the sperm cells may get women pregnant accidentally if they get past the uterus into the fallopian tubes. This could be a problem because of the damage the drug-infused sperm cell could cause. This and other issues are part of the ongoing research to deal with every possible scenario before using human sperm cells for trials. Bio-hybrid delivery systems show great potential, spermbots have also been tested in assisted fertility since 2016.