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.