Why does male and female immune systems consider sperm cells to be enemies?

Answer 1

Every cell in an individual's body has specific markers so the individual's immune system will recognize it as "self". Anything that doesn't have the proper "self" markers, will be recognized as foreign and trigger an immune response (this is one of the major reason why after organ transplant, people have to be put on immuno-suppressant therapy).

Sperm also have these markers, so upon insemination, it's possible for the sperm to be recognized as foreign and killed off. That usually doesn't happen because there are other components in semen that help to suppress the female's immune response (otherwise, conception would be quite rare). If you collect sperm from semen and wash away them other components, they will trigger an immune response because, again, the sperm will have certain markers that label it as foreign.

Hope this helps.

Answer 2

Male and female immune systems do not consider sperm cells to be enemies. Instead, the immune system is programmed to recognize foreign invaders such as bacteria or viruses. In the female reproductive system, mechanisms are in place to protect sperm cells from the immune response to ensure successful fertilization.