An established cell culture system of isolated human endometrial stromal and epithelial cells has been used to study the effects of oestrogen and progesterone, as well as their antagonists, upon ...endometrial cells. Normal hormonal regulation in vivo was investigated simultaneously in endometrial tissue samples taken at different phases of the menstrual cycle. Several marker molecules analysed by immunohistochemistry appeared to depend strongly on endocrine regulation and could be traced in culture. Immunohistochemically, basic parameters of cell biology were identified in vitro, e.g. cell proliferation (Ki-67), adhesion molecules (β3 integrin) and paracrine factors (leukaemia inhibitory factor). The most reliable parameters to assess hormonal influences were oestrogen and progesterone receptor molecules. Immunohistochemical localization could be improved by molecular biological analysis using RT-PCR. In the presence of oestrogen, a significant expression of hormone receptors was also shown by RT-PCR, and withdrawal of oestrogens and addition of gestagen, i.e. medroxyprogesterone acetate, caused receptor downregulation. Addition of the anti-oestrogen ICI 182.780 to cell-culture medium significantly decreased the synthesis of progesterone receptors. Keywords:endometrial cell culture/marker molecules/oestradiol/oestradiol antagonist/progestin
Data from mouse tumor models suggest that tumor-associated monocyte/macrophage lineage cells (MMLCs) dampen antitumor immune responses. However, given the fundamental differences between mice and ...humans in tumor evolution, genetic heterogeneity, and immunity, the function of MMLCs might be different in human tumors, especially during early stages of disease. Here, we studied MMLCs in early-stage human lung tumors and found that they consist of a mixture of classical tissue monocytes and tumor-associated macrophages (TAMs). The TAMs coexpressed M1/M2 markers, as well as T cell coinhibitory and costimulatory receptors. Functionally, TAMs did not primarily suppress tumor-specific effector T cell responses, whereas tumor monocytes tended to be more T cell inhibitory. TAMs expressing relevant MHC class I/tumor peptide complexes were able to activate cognate effector T cells. Mechanistically, programmed death-ligand 1 (PD-L1) expressed on bystander TAMs, as opposed to PD-L1 expressed on tumor cells, did not inhibit interactions between tumor-specific T cells and tumor targets. TAM-derived PD-L1 exerted a regulatory role only during the interaction of TAMs presenting relevant peptides with cognate effector T cells and thus may limit excessive activation of T cells and protect TAMs from killing by these T cells. These results suggest that the function of TAMs as primarily immunosuppressive cells might not fully apply to early-stage human lung cancer and might explain why some patients with strong PD-L1 positivity fail to respond to PD-L1 therapy.
After its original description as a steroid-dependent protein in the rabbit uterus, uteroglobin became one of the best characterized
proteins. However, detailed knowledge of its physiological role ...remains an enigma. In this study we investigate how its structure
is phylogenetically conserved in the horse compared to other mammalian species. Northern blot analysis showed that in horses,
the main expression of uteroglobin appears in lung, uterus, and prostate tissues. Western blot analysis demonstrated that
the dimeric form of uteroglobin is found predominantly in biological compartments. Using a RACE-PCR technique, we cloned and
sequenced the full-length cDNA (473 base pairs) that encodes equine uteroglobin. The nucleotide sequence was shown to characterize
the primary structure of this protein. This enabled us to add equine uteroglobin to a comparative amino acid alignment of
8 other uteroglobin molecules, and finally, to unravel 14 evolutionary completely conserved amino acids. We summarize these
results with a computer-based 3-D model of horse uteroglobin, and discuss new concepts on the physiological role of uteroglobin,
in particular as a specific binding protein.
CENP-A (CID in flies) is the histone H3 variant essential for centromere specification, kinetochore formation, and chromosome segregation during cell division. Recent studies have elucidated major ...cell cycle mechanisms and factors critical for CENP-A incorporation in mitosis, predominantly in cultured cells. However, we do not understand the roles, regulation, and cell cycle timing of CENP-A assembly in somatic tissues in multicellular organisms and in meiosis, the specialized cell division cycle that gives rise to haploid gametes. Here we investigate the timing and requirements for CID assembly in mitotic tissues and male and female meiosis in Drosophila melanogaster, using fixed and live imaging combined with genetic approaches. We find that CID assembly initiates at late telophase and continues during G1 phase in somatic tissues in the organism, later than the metaphase assembly observed in cultured cells. Furthermore, CID assembly occurs at two distinct cell cycle phases during male meiosis: prophase of meiosis I and after exit from meiosis II, in spermatids. CID assembly in prophase I is also conserved in female meiosis. Interestingly, we observe a novel decrease in CID levels after the end of meiosis I and before meiosis II, which correlates temporally with changes in kinetochore organization and orientation. We also demonstrate that CID is retained on mature sperm despite the gross chromatin remodeling that occurs during protamine exchange. Finally, we show that the centromere proteins CAL1 and CENP-C are both required for CID assembly in meiosis and normal progression through spermatogenesis. We conclude that the cell cycle timing of CID assembly in meiosis is different from mitosis and that the efficient propagation of CID through meiotic divisions and on sperm is likely to be important for centromere specification in the developing zygote.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
► Detailed overview on safety assessment aspects of railway axles. ► Combines questions of basic and applied research with questions of practical application. ► Proposals for further improvement of ...railway axle safety.
The paper gives an overview on safe life and damage tolerance methods applied to railway axles. It describes failure scenarios due to fatigue crack initiation and propagation. Besides common aspects of design, specific features such as corrosion and impact damage from flying ballast are discussed which may reduce the fatigue strength of axles during service. Potential effects of non-metallic inclusions from the steel manufacturing process are addressed in the context of the very high number of loading cycles railway axles are designed for. With respect to damage tolerance general lines of fracture mechanics residual lifetime analyses are introduced. More specific discussion is provided on aspects such as the threshold value of fatigue crack propagation and reliability aspects of non-destructive inspection.
To compare cytokine expression profiles of decidua basalis (containing trophoblast cells) and decidua parietalis (without trophoblast cells) for determination of microenvironments in human first ...trimester decidua.
Retrospective study.
School of Medicine, RWTH University of Aachen, Aachen Germany, and Bourgognekliniek Maastricht, Maastricht, The Netherlands.
Forty-six women who had undergone elective first-trimester termination of viable pregnancy at 5 to 12 weeks.
Quantitative cytokine protein analysis in decidual tissues by enzyme-linked immunosorbent assay, qualitative cytokine messenger (m)RNA analysis in isolated decidual cell samples, and comparative mRNA and protein analysis in tissues of decidua basalis compared with decidua parietalis.
Interleukin-2, interferon-γ (Th-1), interleukin-4 (Th-2), and interleukin-1β proteins are expressed in the human first-trimester decidua. Interleukin-2, interferon-γ, and interleukin-4 mRNA mainly derive from the decidual tissue leukocytes. Interleukin-1β mRNA is expressed by all decidual cell types. Interferon-γ mRNA and protein is detected predominantly in the decidua basalis, which contains trophoblast cells.
Microenvironments are established topographically by different expression of cytokines in decidua basalis and decidua parietalis. These locally specific patterns are indicative of fetomaternal cross-talk. Higher interferon-γ concentrations in decidua basalis may influence leukocyte differentiation (e.g., macrophage activation) and trophoblast invasion (e.g., by induction of expression of major histocompatibility complex).
We have peformed three searches for high-frequency signals in the solar neutrino flux measured by the Sudbury Neutrino Observatory (SNO), motivated by the possibility that solar g-mode oscillations ...could affect the production or propagation of solar {sup 8}B neutrinos. The first search looked for any significant peak in the frequency range l/day to 144/day, with a sensitivity to sinusoidal signals with amplitudes of 12% or greater. The second search focused on regions in which g-mode signals have been claimed by experiments aboard the SoHO satellite, and was sensitive to signals with amplitudes of 10% or greater. The third search looked for extra power across the entire frequency band. No statistically significant signal was detected in any of the three searches.
The transcription factor MEF2D is important in the regulation of differentiation and adaptive responses in many cell types. We found that among T cells, MEF2D gained new functions in Foxp3+ T ...regulatory (Treg) cells due to its interactions with the transcription factor Foxp3 and its release from canonical partners, like histone/protein deacetylases. Though not necessary for the generation and maintenance of Tregs, MEF2D was required for the expression of IL-10, CTLA4, and Icos, and for the acquisition of an effector Treg phenotype. At these loci, MEF2D acted both synergistically and additively to Foxp3, and downstream of Blimp1. Mice with the conditional deletion in Tregs of the gene encoding MEF2D were unable to maintain long-term allograft survival despite costimulation blockade, had enhanced antitumor immunity in syngeneic models, but displayed only minor evidence of autoimmunity when maintained under normal conditions. The role played by MEF2D in sustaining effector Foxp3+ Treg functions without abrogating their basal actions suggests its suitability for drug discovery efforts in cancer therapy.
Glucose is catabolized by two fundamental pathways, glycolysis to make ATP and the oxidative pentose phosphate pathway to make reduced nicotinamide adenine dinucleotide phosphate (NADPH). The first ...step of the oxidative pentose phosphate pathway is catalyzed by the enzyme glucose-6-phosphate dehydrogenase (G6PD). Here we develop metabolite reporter and deuterium tracer assays to monitor cellular G6PD activity. Using these, we show that the most widely cited G6PD antagonist, dehydroepiandosterone, does not robustly inhibit G6PD in cells. We then identify a small molecule (G6PDi-1) that more effectively inhibits G6PD. Across a range of cultured cells, G6PDi-1 depletes NADPH most strongly in lymphocytes. In T cells but not macrophages, G6PDi-1 markedly decreases inflammatory cytokine production. In neutrophils, it suppresses respiratory burst. Thus, we provide a cell-active small molecule tool for oxidative pentose phosphate pathway inhibition, and use it to identify G6PD as a pharmacological target for modulating immune response.
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