Building a cancer-free ovary

Women diagnosed with cancer often face the risk that chemotherapy or radiation treatment will damage their ovaries and leave them infertile. Doctors can remove and freeze all or part of the ovary and its follicles to transplant after treatment, but ovarian tissue can sometimes harbor cancerous cells and reintroduce malignancy after transplant.

But recent research at University Hospital of Copenhagen Rigshospitalet in Denmark could offer women another option.

A team of researchers there created the first functional bioengineered ovary. Postdoctoral fellow Susanne Pors presented the research last week at the annual meeting of the European Society of Human Reproduction and Embryology in Barcelona, Spain.

The researchers in Copenhagen harvested early-stage follicles from the ovarian tissue of human patients about to undergo chemotherapy. They then chemically stripped cells from the tissue, leaving only a cancer-free scaffold of proteins and collagen, which they reseeded with the harvested follicles. When the researchers transplanted the reseeded ovarian tissue into mice, the scaffold supported the survival and growth of the follicles. The researchers noted that human clinical trials are likely five to 10 years away.

Paige Cunningham, executive director of The Center for Bioethics and Human Dignity, told me this research represents a very positive step toward one day offering women facing medical treatment that could impair their ovaries the ability to naturally conceive a child in their own bodies. And because the ovaries trigger so many important hormones, this technology may potentially offer other, non-reproductive health benefits.

But Cunningham also cautioned that reproductive research “is a Wild Wild West.” The goal of this study, and all reproductive studies, is ultimately to produce a baby. But after the birth, researchers often do no further studies, so little data exists on the safety and efficacy of these procedures for the children they produce. In one case, shortly after the birth of a child produced through an experimental procedure involving three parents who all provide DNA during the conception of baby, the birth parents withdrew from all future follow-up, leaving researchers with no information regarding the child's health.

“In reproductive therapy there are always two patients, and the child always bears the ultimate risk,” Cunningham said.

A Congolese boy receives an oral polio vaccine at a relief camp in Gisenyi, Rwanda. Associated Press/Photo by Karel Prinsloo (file)

Polio outbreak threatens global eradication

Just on the heels of the recent Ebola scare in the Democratic Republic of the Congo, a polio outbreak in the same country now threatens global attempts to eradicate the crippling and potentially deadly disease.

The recent incidence of polio, which has paralyzed 29 children so far, is spreading. In June, officials confirmed a case of polio on the other side of Congo from the initial outbreak. Two weeks later, another case appeared in the northeast corner, close to the Ugandan border. Michel Zaffran, head of the World Health Organization’s Global Polio Eradication Initiative (GPEI) described the situation as the most worrisome polio outbreak in recent times, Science Magazine reported.

Global efforts to immunize children have reduced polio cases by 99.9 percent. But the prevention that saves can also sicken. Oral polio vaccines contain weakened forms of the live virus, which has now mutated and become capable of sickening people and spreading.

In 2016, health experts determined that vaccines currently cause more cases of polio than “wild viruses” (those naturally occurring in the environment). In April of that year, the GPEI removed the type 2 virus, one of three polio strains, from vaccines. Immunization efforts have successfully eradicated the wild type 2 virus. But since the GPEI removed type 2 from the vaccine, immunity has waned, and vaccine-induced type 2 polio continues to spread from viruses introduced before they were taken out of oral vaccines. The stage is set for an explosive outbreak, according to Zaffran.

The GPEI now has a stockpile of new oral vaccines that target only the type 2 virus. Zaffran is hopeful that judicious use of those vaccines can stop the current outbreak without causing another one. But Congo poses a special challenge because of its remote villages, deteriorating infrastructure, and inadequate health system. —J.B.

A Congolese boy receives an oral polio vaccine at a relief camp in Gisenyi, Rwanda. Associated Press/Photo by Karel Prinsloo (file)

Too much information

DNA evidence has become increasingly important in criminal investigations, but a new forensic approach makes it possible to gain much more personal data about a suspect than ever before. Until now, forensic DNA studies analyzed only DNA sequences, but the new approach will allow researchers to study the chemical compounds attached to the top of these sequences. Using this method, which is still in the experimental stage, forensic investigators will be able to not only identify age, ethnicity, and eye color, but also to detect an abundance of health information.

Obtaining more identifying information will improve the accuracy of DNA investigations, but some ethicists have voiced concerns about the privacy issues involved in revealing such personal information. And these chemical markers are heritable, so it isn’t just the question of a suspect’s privacy rights but also those of the individual’s children, parents, and siblings, scientist Bram Bekaert told Science Magazine. Bekaert, who published a commentary on the new approach in the July issue of the journal Trends in Genetics, suggested the government develop laws that would restrict the information a forensic scientist can give to police and legal investigators. —J.B.

A chocolatey currency

Chocoholics may carefully guard their stash of the sweet treat, but a new archaeological study, published in Economic Anthropology, suggests that ancient Mayans actually used chocolate as currency. Mayan artwork shows the ancient people loved a good hot cup of frothy cocoa, and by the eighth century their passion for the delicacy led to using dried and fermented cocoa beans as payment for goods and services.

Cocoa perhaps became valuable to the Mayans because the finicky nature of cocoa trees made its produce precious, the study’s author said. —J.B.