Modulatory effect of prostaglandin E2 on the immune response in mice, with special reference to anti-sperm immunity.

The intraperitoneal administration of prostaglandin E2 (PgE2) considerably delayed the rejection of allogeneic skin grafts, both in the primary (first set) and secondary (second set) reaction, and inhibited the production of plaque-forming cells after antigenic stimulation with sheep red blood cells. In addition, the treatment of mice with PgE2 during their immunization with allogeneic epididymal spermatozoa resulted in a markedly slower rejection of the following skin grafts from the donor's strain in comparison with the animals injected with spermatozoa only. Evidence was also found concerning the immunosuppressive effect of PgE2 on the humoral immune response against sperm antigens.

Further immunological studies on components of the kallikrein-kinin system. Immunomodulatory effect in mice.

Porcine pancreatic kallikrein and synthetic bradykinin usually applied for stimulation of sperm motility were administered in mice to study their effect on the immune response. Humoral immune response was recorded by the number of direct plaque-forming cells in spleen-cell suspension, and the cell-mediated immune response was determined by the survival rate of allogeneic skin grafts. Kallikrein exerted suppressive influence both on the primary and on the secondary humoral immune response accompanied by well-expressed splenomegaly but bradykinin stimulated the humoral immune response.

Effect of antisperm sera on the acrosomal proteolytic activity in vitro.

The effect of isoimmune antisperm sera from heifers and the effect of sera from cows and women with unexplained infertility were studied on the sperm acrosomal proteolytic activity (SAPA) of bull and human spermatozoa. All the sera were preliminarily tested by the method of Kibrick, and the cow sera were additionally tested by method of Isojima et al. Ejaculated bull and human spermatozoa were incubated in a medium containing antisera.

Certain immunological relationships between the pancreatic kallikrein and spermatozoa.

The immunological relationship between kallikrein and acrosomal extracts from bull, ram, boar, and human spermatozoa was studied. Highly purified porcine pancreatic kallikrein was used and rabbit antikallikrein serum was produced. The immunochemical analysis did not reveal any antigenic relationship between kallikrein and the acrosomal extracts from spermatozoa of these species.

Effect of kallikrein on bull sperm motility in vitro.

The application of kallikrein--a kinin-releasing porcine pancreatic kininogenase--exerted considerable stimulation of bull sperm motility in vitro. The kallikrein was used in two concentrations: 1 and 100 KU/ml semen. Both concentrations gave similar effect: at the 4th hour of incubation at room temperature the motility rate of spermatozoa exceeded five and four times, respectively, that of the control samples.