[Immunobiology of vesicular mole and choriocarcinoma]

Molar tissue expresses HLA antigens evidenced in the father. These antigens are present on the trophoblastic extravillous tissue, not on the syncytium and cytotrophoblast. These antigens show some characteristics of Qa murine antigens mapped in the HLA system linked to class I antigens. Antibodies anti HLA against the partner antigens and lymphocytotoxic antibodies have been evidenced in the serum of patients with vesicular mole. In vesicular mole the production of antibodies should be determined by the immunogenicity of cells that infiltrate the decidua, expressing paternal HLA antigens. It has been demonstrated that the recognition of "not self" antigens in the mother should stimulate a cellular immune response. We do not know why the tumor grows. Maybe the woman is not able to produce anti HLA antibodies although recognizes them as "not self", or the patients is not antigenically stimulated because there is immunocompatibility between the two partners. The literature shows that the development and progression of the disease are stimulated by histocompatibility, although this factors does not seem fundamental. If the two partners are histocompatible the tumor can be less immunogenic, so the mother shows a lower response and the growth of the tumor appears to be favoured.