What are blocking antibodies? Efficacy of blocking antibodies

Many friends may not have heard of blocking antibodies. Blocking antibodies are good for pregnant women because, generally speaking, blocking antibodies can hinder the attack of the mother's immune cells on embryonic cells and have a protective effect on embryonic cells.

In the serum of normal pregnant women, there is a specific IgG antibody against spouse lymphocytes, which can inhibit lymphocyte response (MLR), block the cytotoxic effect of maternal lymphocytes on cultured trophoblasts, prevent helper T cells from recognizing inhibitors of fetal antigens, and prevent the mother's immune system from attacking the embryo. Blocking antibodies (BA) block the production of macrophage migration inhibitory factor (MIF) by lymphocytes stimulated by alloantigens.

type

The main types of blocking antibodies discovered so far are as follows:

1. Anti-warm B cell antibodies: Anti-HLA-D/DR antibodies on the surface of fetal B lymphocytes;

2. Anti-cold B cell antibodies: non-HLA cold B antibodies;

3. Anti-specific antibodies: Genetic antibodies against HLA-D/DR receptors on the surface of maternal helper T cells;

4. Anti-TLX antibody: It is an antibody against common antigens of villi and lymphocytes, which can block mixed lymphocyte reaction;

5. Anti-Fc receptor antibodies: non-cellular blocking antibodies that block Fc receptors on husband's B lymphocytes;

6. Anti-paternal complement-dependent antibodies (APCA).

About the mechanism of action of blocking antibodies

In vitro studies have shown that during pregnancy the mother can produce sensitized T cells that can destroy germ cells. However, the killing function of sensitized T cells can be inhibited by specific antibodies. However, about 80%-90% of women with habitual abortion cannot detect such specific blocking antibodies, and uninhibited cytotoxic cells exist in their bodies. These cells can directly act on the embryo or indirectly damage the fetus or placenta by releasing inflammatory mediators, leading to miscarriage.