Antigens produced by the testes that scientists thought were forever withdrawn from the rest of the body actually have contact with the immune system, a new study finds. This unforeseen interaction has revealed itself to be the cause of some autoimmune diseases, cancer vaccine failure, and some cases of male infertility.
Scientiss previously thought the testes had no contact with the immune system, thanks to an “impenetrable wall of cells.” Recent research findings from the University of Virginia, published in the Journal of Clinical Investigation indicate that there is indeed a wall, but there’s also a hole in the wall that opens in “only one direction.”
Antigens are best described as a substance that triggers an immune response, mainly the production of antibodies. The body is accustomed to recognizing antigens from pathogens that may enter the circulation, but the testes also produce their own antigens during sperm production. In a healthy situation, antigens created by the body’s own tissues are ignored by the immune system, recognized as “self” cells.
What this means for cancer vaccines
Cancer vaccine technology is built on targeting antigens that the immune system is also attacking, with the idea of keeping self cells safe because the immune system generally ignores them. However, if a cancer vaccine was designed to target any of the antigens released by the testes, the vaccine would not have the desired effect, as the immune system ignores those antigens.
“The testes antigens can be divided into those which are sequestered and those that are not,” explained Kenneth Tung, MD, from the University of Virginia. “Antigens which are not sequestered would not be very good cancer vaccine candidates.”
Tung and other University of Virginia researchers are already considering options to overcome the unexpected interaction between antigens from the testes and the immune system. Potentially, they said, doctors could determine which antigens a patient’s cancer cells release and specialize their cancer vaccine treatment according to their specific antigen profile, keeping in mind any antigens released by the testes that the immune system will not recognize as a threat.
What this means for male infertility
The immune system is prone to error-making, and it is possible that some immune cells fail to ignore antigens originating from the testes, instead launching an attack on these cells as if they were dangerous pathogens. Researchers believe that this mistake is a result of dysfunctional regulatory T cells, which are charged with maintaining a balance within the immune system, preventing inflammation where there should be no inflammation.
Experts estimate that around 12 percent of men facing infertility problems have an autoimmune response to blame. But like knowing more about the exact cause can help doctors make cancer vaccines more effective, being aware of this particular cause of infertility could help doctors develop new treatments.