Antimicrobial effect of protein(s) isolated from a marine mollusc Telescopium telescopium.

Ammonium sulfate precipitated protein (SF-50) isolated from the spermatheca gland of Telescopium telescopium, an invertebrate marine snail, showed antimicrobial effect on Escherichia coli. The antimicrobial effect varied with the concentration of "SF-50" used and the effect was found to be comparable to antibiotics like amikacin, contrimoxazole and gentamycin in disc diffusion test. The "SF-50" was devoid of erythrocyte haemolysis property.

Anti-implantation effect of a bone-marrow cytokine-BIM.

Successful implantation of blastocyst is dependent upon a cytokine induced localized immunosuppression at uterus. BIM, a bone marrow secreted bio-immunomodulator (BIM) has been observed to have positive immunomodulatory activity in immunosuppressed cases. As pregnancy is associated with immunosuppression upregulation of the suppressed immune system by injection of BIM (conc. 0.08 microg/g b.wt once in rats b.wt. <150 gm or 0.2 microg/g b.wt thrice in rats weighing > 160 gm) is believed to prevent implantation. The anti-implantation action of BIM is probably mediated via mononuclear cells at site of uterus, the effect is reversible and a single dose did not affect the estrous cycle. Multiple dose of BIM however, produce prolonged diestrous and this is probably an autonomic phenomena.

A search for immunocontraceptive agent from marine sources--role of antispermatheca globulin of Telescopium telescopium on fertility regulation in male rat.

Polyclonal antisera were developed in rabbits against 'spermatheca', the reproductive gland of T. telescopium, a marine mollusc. The gland contains spermatozoa. Antisera and its IgG fraction (ASTG) indicated common antigenic determinants by immunodiffusion and had titer values 81920 and 1280 against crude antigen extract. Cycling female rats when exposed to passively immunized male rats with different doses of ASTG, had reduction in implantation sites and litter size. Females had pseudopregnancy when exposed to higher doses of immunized males and had normal cycle after 20 days in average. ASTG in male rats caused decrease in weight of the reproductive glands, alteration in sperm concentration, motility and morphology, formation of multinucleated giant cells and vacuoles leading to arrest of spermatogenesis and reduction in seminiferous tubular diameter. The effects were dose dependent with reversible infertility. The results indicate presence of a common antigenic determinants which cross-react with vertebrates and existence of common relation through phylogenetic evolution and their immune responses.

Effect of RMI 12,936, an antiprogestational steroid on decidual cell reaction and embryos in rat.

Subcutaneous administration of RMI 12,936 at a dose level of 2 mg/rat on day 5 of unilaterally pregnant rat having trauma-induced decidual cell reaction (DCR) in the contralateral uterine horn, suppresses DCR, induces resorption of implanted embryos and leads to decrease in the plasma level of progesterone. Progesterone replacement (D 5-8) in this situation reverses DCR suppressive effect of RMI 12,936 but fails to prevent resorption of implanted embryos. It is concluded that possibly the drug simultaneously exerts embryotoxic as well as luteolytic effects, but these effects are independent.