New discovery offers hope for male infertility treatment

Male infertility.

Researchers have identified the types of cells in the testicles of both newborns and adults, opening the way for new strategies for treating male infertility with stem cells.

 

The dream of childbearing is shattered on the rock of infertility that affects up to 15% of couples of reproductive age worldwide, but a US research team has made new discoveries that give hope to millions and open the way to innovative strategies for treating male infertility with stem cells.

 

Considering that the testicles are the storehouse of sperm cells that help men fertilize eggs in women, and thus have children, the research team at the University of California-San Diego School of Medicine developed a pioneering technique for identifying the types of cells in the testicles of humans, both newborns, and adults.

 

The testes of normal, healthy men produce more than 1,000 sperm per second, in part from a special type of stem cell called spermatogonia, also known as maternal sperm cells. Retaining these cells has allowed many people to father children, even after the age of 65.

 

In a study published in the scientific journal Cell Roberts, the researchers explained that these cells have been extensively studied in rodents and attempts to grow them in the laboratory for clinical purposes have had limited success, but they have not been well studied in humans.

 

To study the mechanism that contributes to the development of these cells in humans, the research team used RNA sequencing technology to paint a clearer picture of human sperm stem cells and how they are formed, they also developed tools to better isolate them.

 

In the testes of adult men, the team studied two groups of cells, primary sperm cells, and sperm stem cells, and the researchers were able to discover 4 new groups and clusters of sperm stem cells, as well as identify the genes responsible for them, and the proteins that are produced from these genes.

 

The researchers also discovered that the testes of newborn males contain both primary sperm cells or germ cells, in addition to sperm stem cells, and that the process of stem cell transformation into sperm is affected by surrounding conditions, such as hormone levels, acidity rate, temperature, and others.

 

 

Unknown functions

"The progress in studying the RNA of sperm stem cells opens the door to the possibility of developing stem cells to treat male infertility," said Miles Wilkinson, the leader of the research team.

 

And "Wilkinson" adds that "RNA sequencing monitors the activity of hundreds of genes in the genome of a single cell, and since each cell type contains a different set of active genes, this technique allows the identification of new cell types, and by applying this approach to the testis, we discovered many Different stages of primary spermatocytes in the human testis".

 

And about the presence of primary sperm cells and sperm stem cells in newborns, although they do not need them to produce sperm until after puberty, "Wilkinson" pointed out that given that sperm stem cells are not necessary to generate sperm until adulthood, this finding raises the possibility of These cells to perform hitherto unknown functions in infants and young children.

 

Regarding the significance of the results, he revealed that they could help researchers develop inducers for the proliferation of sperm stem cells in the laboratory; produce enough of them, and grow them for clinical applications in humans.

"The results demonstrate the importance of future clinical studies of the use of sperm stem cells as a method of treating infertile men, including cancer patients who have been infertile due to chemotherapy," Wilkinson said.

 

For his part, "Hani Selim" - consultant of andrology and infertility, head of the scientific research ethics committee at the National Institute for Research in Endemic and Liver Diseases in Cairo - said in statements to Al-Alam: "The researchers focused in their research on monitoring the biological markers that distinguish sperm cells in the testicles. To discover ways to develop sperm from stem cells into whole sperm cells.

 

"Salim" adds, "There is a group of people who suffer from a problem in the development of sperm and reaching their final state that leads to reproduction, due to some diseases such as varicoceles, some genetic diseases, and some cancer drugs, and this is the category that scientists aim to search for treatments It enables her to conceive.”

 

 

Intractable male infertility

For his part, Amr Al-Ahwany, a consultant andrologist at Cairo University, said that the scientists' findings are a new discovery that leads to the treatment of intractable male infertility. In an interview with "Science", he added that the team succeeded in drawing a map linking the development of sperm cells in children, and the sperm stem cells responsible for producing sperm in adults.

 

Al-Ahwany explained that adult men usually have two types of sperm stem cells, the first is regenerative sperm stem cells, and the second is primary sperm cells that develop into sperm to fertilize female eggs and achieve pregnancy, which distinguishes sperm stem cells from other stem cells in the human body.

 

He pointed out that male infertility has multiple causes, including that the testicles contain primary sperm cells, but they do not complete into sperm, for various reasons, including taking chemotherapy for cancer, having an undescended testicle, or having a genetic defect that prevents the sperm from completing in its form. These men will benefit from this discovery, but those whose testicles do not contain primary sperm cells will not benefit from this discovery.

 

 

Ethical controls

Regarding the conformity of this preliminary research with the ethics of scientific research with regard to stem cells, "Salim" indicated that this mechanism that scientists seek to develop completely matches the general rules of ethics for stem cell research, for reasons, the first of which is that it relies on cells taken from the husband's sperm to fertilize them in an egg The wife is during an already existing marital relationship, after which the fetus is placed in the womb, in an already existing marriage.

 

On the other hand, this type of treatment could violate the ethics of stem cell research if this process takes place in a relationship that does not currently exist; Due to the death of the husband and the preservation of his sperm, or the divorce of the wife during the operation, in order to preserve the lineage.

 

Selim noted the need for bio-safety to be available in biobanks and stem cell clinics; Because this process must take place in specialized microbiological laboratories with the highest levels of biosecurity that take into account the relative risks of contamination with microorganisms and pathogenic microbes, and require measures, including protective clothing, control of air entry and movement in the laboratory, and dealing with confidentiality and caution with the waste generated from this laboratory If biosecurity is not available, these cells can become infected with bacteria and pass to the patient.