Immune infertility
The man himself develops anti-sperm immunity, or the woman develops anti-sperm immunity Infertility caused by sperm immunity. 2% to 10% of infertile men and women are caused by immune factors. There are generally three conditions that cause immune infertility, namely autoimmunity in men, anti-sperm circulating antibodies and anti-sperm tissue antibodies in women. Research on reproductive immunology shows that sperm is an autoantigen for men and can cause autoantibodies. The higher the sperm antibody titer in a man\’s serum, the lower the power of ejaculated sperm, the more agglutination, the weaker the ability to pass through cervical mucus, and the worse the fertility.
Factors that can cause sperm autoimmunity include: ① Testicular trauma or surgery; ② Testicular and Infection of the accessory sex glands (especially the prostate and seminal vesicles); ③ obstruction of the output ducts (such as epididymis, vas deferens); ④ testicular degeneration in old age. These factors can cause sperm antibodies to come into contact with the autoimmune system, T cell sensitization and orchitis. Women\’s immune response to sperm antigens also includes cellular immunity and humoral immunity, which can have systemic reactions and local reactions. It has been reported that among infertile women, the highest is 72% and the lowest is 10% with circulating sperm agglutination antibodies. Immediately after sexual intercourse, the patient develops painful and itchy erythema, edema of the lips, face, tongue and pharynx, followed by severe asthmatic dyspnea, mucosal congestion, uterine cramps, and finally loss of consciousness. Clinical manifestations peak 30 minutes after sexual intercourse and subside within 24 hours. The main site of local immunity to sperm in the female reproductive tract is the cervix, the endometrium and fallopian tubes have a weak effect, and the vagina has a minimal effect. Because there are sufficient plasma cells in the cervix, immunoglobulins can be secreted in the body or outside the body. Sexual intercourse can be regarded as a process of repeated \”injection of antigens\”, and implantation of fertilized eggs and embryos can be regarded as a \”transplantation\” process. The immunosuppressive function of semen (including sperm and seminal plasma) is a necessary prerequisite to ensure fertilization.
Autoimmunity or alloimmunity to sperm antigens, there are at least two mechanisms that cause infertility:① Interfering with the normal spermatogenesis process, causing azoospermia or oligozoospermia; ② Targeting sperm through antibodiesRole in normal fertility produces infertile effects.
Antibodies also act in the following aspects: ① Prevent sperm from passing through cervical mucus. Sperm agglutination antibodies cause sperm to agglomerate into clumps, blocking sperm swimming. ② Affect sperm enzyme activity and inhibit the dispersion of zona pellucida and corona radiata. After sperm is capacitated in the female reproductive tract, it undergoes acrosome reaction, releases acrosome enzyme, and then combines with sperm and egg. Moreover, sperm antibodies mainly inhibit hyaluronidase activity and interfere with sperm dispersion. ③Seal the antigen site on the acrosome membrane (zona pellucida identification point), inhibit the attachment and penetration of sperm to the pellucida, and prevent sperm and eggs from combining. ④ Research shows that sperm antibodies can prevent the fusion of sperm and egg membranes, leading to infertility. ⑤ Affect embryonic development. Experimental animals that have been actively immunized with sperm can show that their embryos die before implantation. Women with sperm antibodies may also experience miscarriage or embryo attraction. It can be seen that sperm antibodies can affect the embryo after fertilization.
Immune infertility
Immune infertility in Under normal sexual life, the body\’s spontaneous immunity to any link in the reproductive process delays conception for more than two years, which is called immune infertility. Immune infertility can be divided into broad and narrow senses. In a broad sense, immune infertility refers to the body\’s immunity to any tissue antigen in the hypothalamus-pituitary-ovary (testis) axis. Women can present with anovulation and amenorrhea; men can present with reduced sperm or reduced sperm motility. Immune infertility is usually referred to in a narrow sense, that is, except for the presence of anti-sperm immunity or anti-zona pellucida immunity, infertile couples are otherwise normal.
Autoantigens in the reproductive system can stimulate immune responses in both genders, leading to autoimmune infertility, such as male anti-sperm immune infertility and female anti-zona pellucida immune infertility. Sperm antigens can also cause homologous antisperm immune responses in women, which is called homologous antisperm immune infertility.
Research shows that anti-sperm antibodies can cause infertility, accounting for 10% to 30% of infertile patients. There are fewer studies on anti-zona pellucida antibodies. It is generally believed that it can cause female infertility, but many issues have yet to be confirmed.
Immune infertility is a relative concept, which means that immunity reduces fertility and temporarily causes infertility. Whether the infertility state can be sustained depends on the interaction between immunity and fertility. If immunity is stronger than fertility, infertility will occur, and if the latter is stronger than the former, pregnancy will occur. Infertility often has multiple factors coexisting, and immune factors can also be the only cause of infertility or coexist with other causes.
Anti-sperm immunity includes anti-sperm humoral immunity (anti-sperm antibodies) and anti-sperm cell immunity. In normal sexual life, the intervention of semen into the female reproductive tract is similar to tissue transplantation, and the immune response stimulated mayMainly cellular immunity. At present, research on antisperm antibodies has accumulated a large amount of data, but cell-mediated antisperm immunity has not received enough attention and needs further research.
The zona pellucida is a layer of non-cellular gelatin-like acidic glycoprotein membrane surrounding oocytes and pre-implantation eggs. It contains specific sperm receptors and induces acrosome reaction in sperm. Sperm and egg recognition, combination, penetration and prevention of polysperm play an important role in the process of entering the egg. Experimental studies have shown that the zona pellucida antigen can stimulate the same or heterogeneous antibodies to produce an immune response. After the zona pellucida is treated with antiserum, it loses its ability to bind to the same type of sperm; in vivo, zona pellucida antibodies can interfere with the zona pellucida on the surface of pregnant eggs. fall off and prevent implantation. It is currently believed that antibodies to the zona pellucida are one of the causes of female infertility.
This article is provided by Baidu Reading and is excerpted from \”The Clear \”Conception\” Plan\” Author: Sun Jianqiu and Xie Yingbiao