From February, 2065438 to February, 2006, American Journal of Reproduction and Sterility published an article entitled "Experimental Methods for Treating Male Infertility and Preserving Male Fertility", which introduced the existing assisted reproductive methods related to men, and reported that testicular spermatogonial stem cells were cultured in vitro and then implanted into testis to produce new sperm. At the same time, more advanced treatment methods have been introduced to cultivate somatic cells in men's skin or blood into spermatogenic cells, and finally help them obtain their own offspring. The picture below is a good introduction to how to "make" sperm in the laboratory and share it with you.

(gasser. Experimental methods of preserving male fertility and treating male infertility. ? Fertil Steril 20 16.2)

The following is an example:

(a) Sperm obtained from semen or testis is conceived by artificial insemination (IUI) and in vitro fertilization (IVF), that is, intracytoplasmic sperm injection (ICSI) of IVF or oocytes.

(2) Men who can't obtain sperm can obtain spermatogonial stem cells (SSCs) from testis for in vitro culture and proliferation, and then implant them into testis, which may restore their spermatogenic function and naturally conceive. By culturing the suspension of testicular cells in vitro, there will be "polarization" similar to spermatogenic epithelium (the orderly arrangement of spermatogenic cells on the basement membrane), and the morphology of testicular tissue will be reshaped through the newly produced "curved seminiferous tubules", and finally ICSI will be carried out by sperm. Testicular tissue before puberty can be transplanted subcutaneously or in scrotum by autologous transplantation or xenotransplantation to obtain mature sperm for ICSI. In addition, immature testicular tissue can be cultured in vitro to obtain mature sperm. (The latter two are suitable for patients with pre-adolescent tumor undergoing radiotherapy and chemotherapy to store fertility. )

(3) For patients who cannot obtain spermatogonial stem cells from testis, pluripotent stem cells (iPS) can be induced by somatic cells (such as skin or blood) in vitro, further differentiated into germ stem cells (GSCs), and then transplanted into the testis of patients, so it is possible to rebuild spermatogenic function and realize natural pregnancy. In addition, haploid spermatogenic cells can also be directly used for ICSI pregnancy.