Non-classical MHC-E (Mamu-E) expression in the rhesus monkey placenta.

The aim of this study was to characterize the expression of the rhesus HLA-E ortholog Mamu-E, particularly at the maternal-fetal interface. Mamu-E expression was confirmed by locus-specific RT-PCR in the placenta as well as in peripheral blood mononuclear cells (PBMC) and other organs. We evaluated the utility of antibodies recognizing HLA-E (MEM-E/06 against native HLA-E, MEM-E/02 against denatured HLA-E) to detect Mamu-E by flow cytometry/immunofluorescence, Western blot, and immunohistochemistry (IHC). Western blot analysis of cells and selected transfectants confirmed the recognition of Mamu-E but not Mamu-AG by antibodies MEM-E/06 and HC10 but not MEM-E/02. Immunohistochemical staining of frozen sections of rhesus placenta with the MEM-E/06 antibody demonstrated expression in most populations of rhesus monkey trophoblast cells, including villous cytotrophoblasts (strong positive staining), apical membrane of syncytiotrophoblasts (light to moderate staining) and extravillous cytotrophoblasts (moderate to strong staining, especially endovascular trophoblasts in early pregnancy). Expression was not trophoblast cell-specific, especially at term, when endothelial cells in both the chorionic plate and placental villi showed strong staining for Mamu-E. Staining of rhesus extravillous trophoblast cells suggested the co-expression of Mamu-E and Mamu-AG (the rhesus HLA-G homolog) on these cells. MEM-E/06 was shown also to react with differentiating rhesus placental syncytiotrophoblasts in primary culture, detecting intracellular and weak surface expression of Mamu-E. We conclude that the gestation-dependent co-expression of Mamu-E with Mamu-AG in villous and extravillous trophoblast cells suggests important and perhaps complementary but distinct roles of these two non-classical MHC class I loci in pregnancy at the maternal-fetal interface. In addition, the MEM-E/06 antibody will be useful for the detection of Mamu-E at the maternal-fetal interface in the rhesus monkey.

Selective distribution and pregnancy-specific expression of DC-SIGN at the maternal-fetal interface in the rhesus macaque: DC-SIGN is a putative marker of the recognition of pregnancy.

We performed immunohistochemical analysis of DC-SIGN expression at the maternal-fetal interface at different stages of pregnancy in the rhesus monkey. Natural killer cells, monocytes and macrophages were observed in the nonpregnant endometrium, particularly in the luteal phase, and were increased in pregnant endometrium. No DC-SIGN+ cells were observed in the nonpregnant uterus. We observed decidual DC-SIGN+ cells within 1 week of implantation, and they increased in number during the first 5 weeks of gestation. DC-SIGN+ cells showed a clear differential distribution in the decidua in the first 2 weeks of pregnancy, being found only adjacent to the implantation site, in marked contrast to the widespread distribution of CD68+ macrophages and CD56+ NK cells throughout the endometrium. DC-SIGN+ cells also showed a more dendritic morphology than the general CD68+ cell population, and analysis of serial sections indicated an overlapping but not identical localization of these markers. Mature dendritic cells could not be detected as judged by total absence of immunostaining for CD83, CD86, DEC-205, or CD1a. DC-SIGN+ cells were defined as MHC class II+ and CD14+ by flow cytometry. We conclude that DC-SIGN expression is an early response by the primate maternal immune system to the implanting embryo. The selectively distributed population of DC-SIGN+ decidual leukocytes may represent a morphologically and phenotypically distinct subpopulation of decidual macrophages of early pregnancy that could contribute to the establishment of maternal-fetal immune tolerance.

[Effect of thymic peptides on the functional activity of phagocytic cells of donor peripheral blood]. / Vliianie timicheskikh peptidov na funktsional'nuiu aktivnost' fagotsitarnykh kletok perifericheskoi krovi donorov.

The direct action of synthetic peptide preparations, analogous to thymic hormones, on the functions of phagocytic cells was studied. The preparations Thymogen, Neogen and Thymodepressin in a dose of 10 mM produced a stimulating effect on the ingestive activity of the neutrophil, but not monocytic, population. All three preparations also enhanced the formation of oxygen metabolites registered in the luminol-dependent chemiluminescent analysis. The characteristics of spontaneous chemiluminescence (CL) reflecting the basal level of the synthesis of the active forms of oxygen and CL induced by opsomized zymosan significantly increased also in those cases when the preparations were used in a dose of 10 mM. The level of the synthesis of hydrogen peroxide in individual cells could be appraised by the intensity of the luminescence of dichlorofluorescein diacetate (DCF-DA), evaluated with the use of flow cytometry. All preparations produced a stimulating effect on the formation of hydrogen peroxide in monocytes. The reaction of neutrophils was even more active: Neogen (10 mM) produced the twofold change in the intensity of the luminescence of DCF-DA) in neutrophils, Thymogen and Thynodepressin increased the average intensity of the luminescence of DCF-DA by 80% and 60%, respectively.

[Flow laser cytometry for evaluation of the human immune system]. / Protochnaia lazernaia tsitometriia v otsenke immunnoi sistemy cheloveka.

Some flow laser cytometry (FLC) techniques intended for studies of the immune system cells are reviewed. A widespread analytical method is the phenotyping of lymphocytes by the markers they express. The use of FLC permits the evaluation of practically all functional parameters of immunocompetent cells. Thus, to analyze their ingestive and microbicidal activity fluorochrome-labeled microorganisms are used. The apploication of indicator dyes makes it possible to evaluate calcium mobilization and formation of active forms of oxygen. FLC is used for the identification of cytokines inside the cell and in the medium. The authors propose tests for the analysis of the proliferative activity of lymphocytes, the cytotoxicity of natural killers, the evaluation of apoptosis and protein processing with monocytes/macrophages.