Determination of anti-sperm antibodies of IgG class in ejaculate MAR-test

Antisperm antibodies are antibodies that are produced directly to antigens contained in the sperm membrane. In other words, when a man's immune system malfunctions, the body begins to attack the sperm, which becomes the cause of infertility.

Antisperm antibodies in men:

The genetic structure of spermatozoa differs by 50% from that of other cells in a man. Consequently, if the male immune system "meets" spermatozoa, it starts to attack them. Fortunately, under physiological conditions there are a number of mechanisms that protect the male germ cells from autoaggression, but when certain pathological processes develop, the protection mechanisms break down and the spermatozoa are subjected to recognition by the male body's own immune cells as antigenic structures:

1. Normally, spermatozoa develop due to the functioning of Sertoli cells in the testicles, which on the one hand produce a number of enzymes that ensure the growth and development of spermatozoa, and on the other hand form the haematotesticular barrier (a barrier between the bloodstream and the testicle), preventing the penetration of immune cells from the blood into the testicle of men. When this barrier is destroyed by an inflammatory reaction or by mechanical damage, immune cells easily penetrate the haematotesticular barrier and begin to perceive spermatozoa as antigenic structures. It is important to note that antibodies are not produced to the spermatozoon as much as to its individual parts; antibodies are produced to specific protein units that are part of the whole cell. When immune cells encounter an adult spermatozoon under normal conditions, immune reactions will never develop because some of the protein molecules to which autoimmune reactions could develop are covered by other protein structures with which immune cells are familiar and therefore will not be aggressive towards them. Another case is when the barrier is damaged and immune cells encounter protein molecules with which they were not previously familiar, and these in turn have not yet had time to acquire the ability of invisibility.

2. In the process of sperm development there is insufficient production of substances and enzymes for its normal functioning, which may be associated with general exhaustion of the body due to acute and chronic diseases or prolonged starvation. In this regard, the adult spermatozoon may not receive in its arsenal a certain part of the mechanisms that prevent it from being recognised as an antigen by the cellular structures of the female body, for example, the immunosuppressive factor of sperm plasma.

The mixed antiglobulin antibody test (MAР or MAR test) can be used to detect IgG and IgA antisperm antibodies in the native ejaculate. According to the recommendations of the World Health Organisation, this test is only performed in conjunction with a general spermogram, which includes the determination of the main seminal fluid and sperm parameters.

The MAR test is based on mixing an ejaculate sample with latex particles or erythrocytes coated with human IgA and IgG antibodies. An anti-human IgG monospecific antiserum is added to the resulting mixture. The formation of mixed agglutinates indicates that the spermatozoa have IgA or IgG antibodies on their surface. The result is evaluated as "immunological infertility" only if latex particles are attached to at least 50% of normal motile spermatozoa. This test determines the percentage of normal spermatozoa coated with antibodies to the total number of normal spermatozoa with the same characteristics but without antibodies present. The MAR test should be performed when sperm concentration and motility, as assessed by the spermogram, are normal. Morphologically and functionally normal spermatozoa, but with anti-sperm antibodies on their surface, do not participate in the fertilisation process and may be the cause of infertility in men.

Indications for prescription:

• - Diagnosing the causes of infertility in men;

• Diagnosis of immunological infertility in men;

• - Suspected violation of the haematotesticular barrier after infectious diseases, varicocele, cryptorchidism, trauma, surgery, oncological diseases.

Norma:

IgA: 0 - 39.99 % - normal.

IgG: 0 - 39.99 % - normal.

Interpretation of results:

0 - 39.99 % - minimal or no probability of immunological infertility;

> 39.99 % - high probability of immunological infertility.