Suppression of immunoglobulin secretion by soluble annexin II

Transcriptomic analysis of the myometrium during peri-implantation period and luteolysis--the study on the pig model

In pigs, implantation begins with the attachment of embryos to the endometrium. As the process is regulated by the expression of numerous genes, endometrial transcriptomic profiles have been extensively studied in early gravid pigs. However, the myometrium, a secretory tissue, should not be neglected, as it can also participate in the regulation of implantation in early pregnant pigs. To clarify this issue, the transcriptomic profile of the porcine myometrium during the peri-implantation period (i.e. on days 15 to 16 of pregnancy) was compared with the profile observed during luteolysis (i.e. on days 15 to 16 of the oestrous cycle) with an Agilent’s Porcine (V2) Two-Colour Gene Expression Microarray 4 × 44 (Agilent, USA). Analysis of the microarray data revealed that of 526 unique, accurately annotated genes, the expression of 271 unique genes was upregulated, while the expression of 255 genes was downregulated in pregnant versus cyclic myometrium. The in-depth data analysis revealed differential expression of genes encoding for factors involved in immunomodulation, tissue growth and differentiation, and prostaglandin and steroid biosynthesis and action. Moreover, the comparison of the obtained data on the myometrial transcriptome with our previously published results on the endometrial transcriptome allowed us to determine substantial differences in the regulatory function of both tissues. The new insights into the function of the myometrium of early pregnant pigs obtained here are in agreement with our previous results that suggest that this tissue plays an important role in providing optimal conditions for developing embryos. Therefore, the importance of the myometrium as an active embryo signal-responsive tissue during early pregnancy cannot be underestimated.

No immunosuppressive effect of transfected annexin II

Annexin II (AXII) was reported to suppress lymphoproliferation and immunoglobulin production. To investigate this further, the AXII-negative human B-lymphoma cell line Raji was transfected with AXII followed by transfection with p11. Stable transfectants were generated. In vitro immunological effects of Raji, Raji-AXII and Raji-AXII-p11 were compared by using irradiated cells as stimulators for PBM in mixed lymphocyte reactions or by adding the supernatants to lymphoproliferation or ELISPOT cultures. None of the assays provided evidence of significant immunosuppression by AXII. Thus, expression of AXII or AXII plus p11 does not by itself give a cell immunosuppressive ability.

Tolerance to the foeto-placental 'graft': ten ways to support a child for nine months

Tolerance to the foetal 'allograft' has been extensively studied in the past few years, providing interesting new insights. In addition to a potential role for HLA-G, which has been widely discussed, there are hypotheses suggesting roles for several other molecules or cells: leukemia inhibitory factor and its receptor; indoleamine 2. 3-dioxygenase; the Th1/Th2 balance; suppressor macrophages; hormones such as progesterone or the placental growth hormone; CD95 and its ligand; and, as recently proposed, annexin II. Tolerance of the foetal allograft is probably the consequence of a wide panel of mechanisms that may or may not be pregnancy-specific, that are of major or secondary importance and that may be interconnected.

Estrogen targets genes involved in protein processing, calcium homeostasis, and Wnt signaling in the mouse uterus independent of estrogen receptor-alpha and -beta

Estrogen actions in target organs are normally mediated via activation of nuclear estrogen receptors (ERs). By using mRNA differential display technique, we show, herein, that estradiol-17beta (E(2)) and its catechol metabolite 4-hydroxy-E(2) (4OHE(2)) can modulate uterine gene expression in ERalpha(-/-) mice. Whereas administration of E(2) or 4OHE(2) rapidly up-regulated (4-8-fold) the expression of immunoglobulin heavy chain binding protein (Bip), calpactin I (CalP), calmodulin (CalM), and Sik similar protein (Sik-SP) genes in ovariectomized wild-type or ERalpha(-/-) mice, the expression of secreted frizzled related protein-2 (SFRP-2) gene was down-regulated (4-fold). Bip, CalP, and CalM are calcium-binding proteins and implicated in calcium homeostasis, whereas SFRP-2 is a negative regulator of Wnt signaling. Bip and Sik-SP also possess chaperone-like functions. Administration of ICI-182,780 or cycloheximide failed to influence these estrogenic responses, demonstrating that these effects occur independent of ERalpha, ERbeta, or protein synthesis. In situ hybridization showed differential cell-specific expression of these genes in wild-type and ERalpha(-/-) uteri. Although progesterone can antagonize or synergize estrogen actions, it had minimal effects on these estrogenic responses. Collectively, the results demonstrate that estrogens have a unique ability to influence specific genes in the uterus not involving classical nuclear ERs.