Expression of allograft inflammatory factor-1 in mouse uterus and poly (I:C)-induced fetal resorption

PROBLEM: To investigate whether the allograft inflammatory factor-1 (AIF-1) is expressed and plays a role in the reproductive system. METHOD OF STUDY: AIF-1 expression was examined in uteri of non-pregnant and pregnant mice by Northern blot analysis, RT-PCR and immunohistochemistry. RESULTS: The expression of AIF-1 varied during the estrous cycle with a peak at estrus. After the insemination, the expression of AIF-1 mRNA diminished gradually and again increased in the preimplantation or implantation period in allogeneic or syngeneic pregnancy, respectively. Enhanced expressions of AIF-1, tumor necrosis factor-alpha (TNF-alpha) and nitric oxide synthase 2 (NOS2) mRNA were observed in the embryos of resorption-prone pregnancy injected with poly(I:C). CONCLUSIONS: This study demonstrated for the first time that AIF-1 was expressed in uterus. The expression level was associated with the population size of macrophage and varied during the estrous cycle and the pregnancy period. The augmented expression of AIF-1 with concomitant expressions of TNF-alpha and NOS2 mRNA in poly(I:C)-injected mice suggests a correlation between AIF-1 production and fetal resorption.