Implantation-associated gene-1 (Iag-1): a novel gene involved in the early process of embryonic implantation in rat.

Background: In order to study the novel genes related to rat embryonic implantation, a novel implantation-associated gene, Iag-1, was identified and characterized from rat uterus of early pregnancy. Iag-1 was initially derived from suppressive subtracted hybridization of a cDNA library of rat uterus, which was used to analyse differentially expressed genes between the preimplantation and implantation period.

Methods: The full-length cDNA sequence of Iag-1 was cloned from rat uterus on D5.

IFN-gamma promotes apoptosis of the uterus and placenta in pregnant rat and human cytotrophoblast cells.

Growth and development of placentas in all pregnancy periods and that of fetuses in late pregnancy were inhibited after administration of interferon-gamma (IFN-gamma). Apoptosis can be detected by TUNEL at the maternal-fetal interface during normal rat pregnancy. Apoptosis locations at the maternal-fetal interface changed according to the period of pregnancy.

Effect of interferon-gamma treatment on the expression of interleukin-1beta at the maternal-fetal interface of pregnant rats.

In the present study, the possible mechanisms by which interferon (IFN)-gamma affects pregnancy were investigated using the cytokine network model. The IFN-gamma-induced expression of interleukin (IL)-1beta was examined using western blotting, immunohistochemistry and immunofluorescence. The results showed that IFN-gamma treatment significantly decreased the expression of uterine IL-1beta protein during the preimplantation, post-implantation and mid-gestation periods.

Effects of IL-1 beta on RT1-A/RT1-DM at the maternal-fetal interface during pregnancy in rats.

Interleukin-1 (IL-1beta) beta and major histocompatibility complex (MHC) play an important role during pregnancy. Expression of non-classical class MHC II RT1-DM antigen and classical class MHC I RT1-A antigen induced by IL-1beta was examined by Northern blotting, Western blotting and immunohistochemistry. IL-1beta treatment significantly increased the expression of RT1-A and RT1-DM in early and mid pregnancy.

IFNgamma pretreatment sensitizes human choriocarcinoma cells to etoposide-induced apoptosis.

Choriocarcinoma is a malignant trophoblast-derived tumour, which can arise in any type of gestation. Cell proliferation assays showed that interferon gamma (IFNgamma) alone significantly inhibited proliferation of choriocarcinoma JAR and JEG-3 cells. TdT (terminal deoxynucleotidyl transferase)-mediated dUDP nick-end labelling (TUNEL) assays and Hoechst staining indicated that IFNgamma alone could not induce apoptosis of JAR and JEG-3 cells, but IFNgamma could enhance the sensitivity of JAR cells to etoposide-induced apoptosis.

The expression of membrane protein augments the specific responses induced by SARS-CoV nucleocapsid DNA immunization.

Nucleocapsid protein plays a critical role in SARS-CoV pathogenesis, and high-level anti-nucleocapsid antibodies are detected in the patients infected by severe acute respiratory syndrome-associated coronavirus (SARS-CoV). Several studies have shown that there exists an interaction between nucleocapsid (N) and membrane (M) protein. In this paper, we investigate whether the expression of membrane protein can affect the immune responses induced by nucleocapsid DNA immunization.

Effect on expression of RT1-A and RT1-DM molecules of treatment with interferon-gamma at the maternal--fetal interface of pregnant rats.

Background: Recent studies suggest a role for interferon-gamma (IFN-gamma) in the pregnancy process.

Methods: The expression of non-classical class II major histocompatibility complex (RT1-DM) antigens and classical class I major histocompatibility complex (RT1-A) antigens induced by IFN-gamma was examined by reverse transcription-PCR, western blotting and immunohistochemistry.

Results: IFN-gamma treatment increased expression of RT1-DM and RT1-A during early pregnancy and decreased them during mid pregnancy at the maternal-fetal interface.

[Research progress on regulation of class II MHC expression].

Class II MHC antigens play a critical role in the induction of immune responses through presentation of processed antigen to CD4+ T lymphocytes. The absence of MHC II normal expression results in severe primary immunodeficiency diseases, such as the bare lymphocyte syndrome (BLS). Four different MHC II regulatory genes have been identified.

Effect of IFNgamma on caspase-3, Bcl-2 and Bax expression, and apoptosis in rabbit placenta.

The purpose of this study was to determine whether apoptosis in placenta was affected by IFNgamma, which can induce abortion, and whether the effect of IFNgamma on apoptosis resulted from an intrinsic program of apoptosis, which was regulated by Bcl-2 and Bax. DNA fragmentation analysis indicated that cleavage of DNA into 180 bp and its polymers were recognized in placenta in control and IFNgamma treated groups. Quantitative analysis of low molecular weight fragments of DNA revealed a significant increase in cases of 100,000 IU IFNgamma treatment compared with those in normal pregnancy (P<0.