Leukaemia inhibitory factor in the endometrium of the common marmoset Callithrix jacchus: localization, expression and hormonal regulation

In the present study, changes in the immunohistochemical localization of le ukaemia inhibitory factor (LIF) in the endometrium during various phases of ovarian cyclicity of the common marmoset have been reported. LIF was absen t during the early and late follicular phases. LIF was observed mainly in t he cytoplasm of the endometrial glands during the early luteal phase, reach ed maximum intensity during the mid-luteal phase and declined again during late luteal phase. In-situ hybridization also showed a similar cyclic patte rn in the expression of LIF. Stromal cells only showed signals for LIF duri ng the mid-luteal phase. In ovariectomized marmosets, graded dosages of oes tradiol alone failed to induce the appearance of LIF protein. Progesterone treatment following oestradiol priming, however, induced distinct glandular localization of LIF, indicating that LIF is a progesterone-dependent prote in. Thus endometrial LIF is under maternal control and is secreted in respo nse to the increased progesterone concentrations in circulation. it is poss ible that high concentrations of LIF during mid-luteal phase may prepare th e endometrium for blastocyst implantation in marmosets.