Immunotherapy with lymphocytes of male partner for embryo nesting. No evidence to back any benefit

As we all know, our immune system is in charge of protecting us against agents that can cause disease, such as bacteria or viruses. Basically, the immune system detects if an agent is foreign to the body and triggers a reaction in order to kill it. This occurs in this way, except in the case of autoimmune diseases, in which due to different errors the own cells are detected as foreign cells and, consequently, they are attacked.

If we think about the implantation and subsequent development of the fetus in the maternal uterus, this event is considered to be totally exceptional from the immunological point of view since an organism for 9 months will tolerate another with a genetic and immunological make-up different from its own. This tolerance at the uterine level seems to depend on a very delicate balance in which a large number of factors are involved.

In clinical practice, two of the most recurring situations we encounter are implantation failure and recurrent miscarriages. These two events are sometimes highly complicated to tackle since there is still not enough knowledge about them and their highly multifactorial nature. Within these factors, it seems that the immune system may have an important role. For this reason, it has been and continues to be the object of study.

Different therapies have emerged from these investigations, but not all of them with sufficient scientific evidence.

This is the case of immunotherapy with paternal lymphocytes. It consists of applying intradermal injections to the patient composed of lymphocytes (cells of the immune system) of the future father, which supposedly generates a maternal immune reaction that would help accept the embryo, avoiding a rejection that ends in miscarriage or non-pregnancy.

It should be noted that the United States Food and Drug Administration (FDA) prohibits this type of therapy used for implantation failure or miscarriage for unknown causes, and it is not recommended by the World Health Organization (WHO), due to insufficient scientific evidence and possible side effects resulting from its use.

Achieving pregnancy, the correct development of it and finally a healthy baby at home should be the central objective, but grounding treatments in evidence, safety and honesty.

IT MAY ALSO BE OF INTEREST TO YOU:

• Implantation failure and recurrent miscarriage Unit
  
• Reproductive Immunology Unit
• Immune Rejection as a Cause of Miscarriage or Implantation Failure
• Reproductive Immunology: What it is, causes, treatment and how it can affect the achievement of pregnancy

Laura Cascales, a biologist at Instituto Bernabeu.