The goal, he says, is to produce thousands of sperm from a standard tissue biopsy. The company boasts a high success rate in obtaining semen from dozens of tissue samples.
Pastuszak says early tests have shown that lab-produced sperm looks “effectively identical” to naturally produced sperm. However, the procedure is not yet ready to be used to start a pregnancy. Paterna created the embryos as an early test to confirm that the lab-produced sperm were indeed viable. The company plans to conduct a larger and more comprehensive study involving men suffering from infertility. Paterna will extract sperm from their ejaculate or testicular tissue and exploit her method to produce sperm for men. The company will then exploit sperm collected and produced in the lab to fertilize eggs in the lab, compare fertilization rates between the two groups and analyze the resulting embryos for physical and genetic abnormalities.
“This will actually tell us a lot about the effectiveness and safety of this approach. It will tell us whether any mutations arise in the in vitro process,” says Pastuszak. Then, tests of laboratory sperm enabling pregnancy could start as early as next year.
Certain types of medications, intrauterine insemination and conventional in vitro fertilization (IVF) can assist men with reduced sperm quantity or quality. However, for men who do not produce sperm at all, treatment options are more narrow.
“When it comes to male infertility, the most difficult scenarios for clinicians are situations in which men have no sperm,” says Ryan Flannigan, a surgeon specializing in sperm collection at the Vancouver Prostate Center in Canada, which is not part of Paterna. “You see the emotional toll and impact on these individuals and couples.”
For these men, an option is surgery to detect sperm in the testicular tissue. It requires general anesthesia and can take up to four hours, depending on how quickly sperm are found. Even then, surgeons fail to find sperm in a significant percentage of cases.
Paterna’s technology is intended to replace this process and instead involve taking a compact biopsy of testicular tissue in a doctor’s office. This tissue will be sent to Paterna, which will perform in vitro spermatogenesis. The company plans to charge between $5,000 and $12,000 for this procedure.
Flannigan says the Paterna technique can also be used on boys who are undergoing chemotherapy to treat cancer before puberty because the stem cells that make up sperm are present from birth. Juvenile cancer patients have had the option of freezing and preserving testicular tissue for years, but transplanting it back remains experimental and no births have been reported.
Other efforts to produce sperm in the laboratory focus on induced pluripotent stems, skin or blood cells that have been reprogrammed to an embryo-like state. These stem cells can be coaxed into producing any type of cell in the body by following the right set of instructions. Scientists managed to produce functional sperm and eggs from pluripotent mouse stem cells, resulting in well offspring. This technique, known as in vitro gametogenesis, could be used to assist same-sex couples have biological children, as an egg or sperm could hypothetically be produced from a skin sample.
Justin Dubin, a urologist and director of men’s sexual health at Baptist Health Miami Cancer Institute, says Paterna’s progress is stimulating, but cost will be a limiting factor for many patients in the U.S. and other places where infertility treatment is too exorbitant.
“We have so many amazing fertility treatment options to offer, and yet many of them are not covered by insurance,” she says.
“This is a tremendous disservice to our patients and to the world’s population because we are not providing people with the resources to have the family they want.”