Search results for "Cell Differentiation"
showing 10 items of 907 documents
Immunohistochemical characterization of endometriosis-associated smooth muscle cells in human peritoneal endometriotic lesions
2011
Background Smooth muscle cells (SMC) are common components of endometriotic lesions. SMC have been characterized previously in peritoneal, ovarian and deep infiltrating endometriotic lesions and adenomyosis. The aim of this retrospective study was to investigate the extent of differentiation in endometriosis-associated SMC (EMaSMC) in peritoneal endometriotic lesions. Methods We obtained biopsies from peritoneal endometriotic lesions (n = 60) and peritoneal sites distant from the endometriotic lesion (n = 60), as well as healthy peritoneum from patients without endometriosis (control tissue, n = 10). These controls were hysterectomy specimens from patients without endometriosis or adenomyos…
The role of recent thymic emigrant-regulatory T-cell (RTE-Treg) differentiation during pregnancy.
2014
During pregnancy, regulatory T cells (Tregs) have a key role in maternal immune tolerance to the semi-allogeneic fetus. Our previous results showed that the naive CD45RA(+)-Treg pool is functionally improved in pregnant women compared with non-pregnant women. Therefore, we examined the thymic output and differentiation of CD45RA(+)CD31(+) recent thymic emigrant (RTE)-Tregs during normal pregnancy and in the presence of preeclampsia. With the onset of pregnancy, the composition of the total CD4(+)CD127(low+/-)FoxP3(+)-Treg pool changed in the way that its percentage of RTE- and CD45RA(-)CD31(+)-memory Tregs decreased strongly, whereas that of the CD45RA(+)CD31(-)-mature naive (MN)-Tregs did …
Myelosuppressive effects of cytosine arabinoside (Ara‐C) on growth factor‐dependent human long‐term bone marrow cultures (LTBMC)
1992
Freshly isolated human mononuclear cells (5 × 106) were incubated in a Dexter-type long-term bone marrow culture (LTBMC) system to study myelosuppressive effects of cytosine arabinoside (Ara-C) in combination with granulocyte-macrophage colony-stimulating factor (GM-CSF) or interleukin 3 (IL-3). Differential counts (dc) of the nonadherent cell (nac) populations, starting with culture initiation, were performed weekly. After one week of simultaneous incubation of LTBMCs with either cytokine (100 ng/ml) and Ara-C (1 mg/ml), nac numbers were markedly reduced compared to controls. Dc after week 1 of culture demonstrated significant decreases of all myeloid cell fractions except for macrophages,…
The role of regulatory T cell (Treg) subsets in gestational diabetes mellitus.
2014
Physiological changes during normal pregnancy are characterized by an inflammatory immune response and insulin resistance. Therefore, we hypothesize that gestational diabetes mellitus (GDM) may be caused by an inappropriate adaption of the maternal immune system to pregnancy. In this study we examined the role of regulatory T cell (Treg) differentiation for the development of GDM during pregnancy. We used six-colour flow cytometric analysis to demonstrate that the total CD4(+) CD127(low+/-) CD25(+) forkhead box protein 3 (FoxP3(+)) T(reg) pool consists of four different T(reg) subsets: naive CD45RA(+) T(regs), HLA-DR(-) CD45RA(-) memory T(regs) (DR(-) T(regs)) and the highly differentiated …
In the presence of IL-21 human cord blood T cells differentiate to IL-10-producing Th1 but not Th17 or Th2 cells.
2012
Abstract IL-21, a member of the IL-2 cytokine family, is mainly produced by activated CD4+ T cells and controls the activity of immune and also non-immune cells. As a pleiotropic cytokine, IL-21 acts on both innate and adaptive immune responses, suggesting that IL-21 may be a master regulator of the T-cell-dependent adaptive immune response. Although IL-21 is described as mostly promoting inflammation, evidence also suggests inhibitory effects of IL-21. However, its role, particularly in the human neonatal immune system, has not been detailed so far. Here, we assessed the effect of IL-21 in the specific context of the neonatal immune response and delineated differences between the human new…
Hedgehog signaling and primary cilia are required for the formation of adult neural stem cells.
2008
Neural stem cells that continue to produce neurons are retained in the adult hippocampal dentate gyrus. The mechanisms by which embryonic neural progenitors expand and transform into postnatal neural stem cells, an essential process for the continual production of neurons throughout life, remain unknown. We found that radial astrocytes, the postnatal progenitors in the dentate gyrus, failed to develop after embryonic ablation of ciliary genes or Smoothened (Smo), an essential component for Sonic hedgehog (Shh) signaling. Postnatal dentate neurogenesis failed in these mutant mice, and the dentate gyrus became severely hypotrophic. In contrast, expression of a constitutively active Smo (SmoM2…
Activation by mitogens and superantigens of axolotl lymphocytes: functional characterization and ontogenic study.
1996
Urodele amphibians have weak and slow immune responses compared to mammals and anuran amphibians. Using new culture conditions, we tested the ability of lymphocytes of a well-studied salamander, the Mexican axolotl (Ambystoma mexicanum) to proliferate in vitro with diverse mitogenic agents. We demonstrated that the axolotl has a population of B lymphocytes that proliferate specifically and with a high stimulation index to the lipopolysaccharide (LPS) known as a B-cell mitogen in mammals. This proliferative capacity is observed without significant changes throughout ontogenesis. In the presence of LPS, axolotl B lymphocytes are able to synthesize and secrete both isotopes of immunoglobulin d…
Terminal nerve in the mouse-eared bat (Myotis myotis): ontogenetic aspects.
2006
As in other mammals, ontogenesis of the terminal nerve (TN) in the mouse-eared bat (Myotis myotis) starts shortly after the formation of the olfactory placode, a derivative of the ectoderm. During development of the olfactory pit, proliferating neuroblasts thicken the placodal epithelium and one cell population migrates toward the rostroventral tip of the telencephalon. Here they accumulate in a primordial terminal ganglion, which successively divides into smaller units. Initial fibers of the TN can be distinguished from olfactory fibers in the mid-embryonic period. The main TN fiber bundle (mfb) originates from the anteriormost ganglion in the nasal roof, whereas one or more inconstant sma…
Telomere Shortening in Neural Stem Cells Disrupts Neuronal Differentiation and Neuritogenesis
2009
Proliferation in the subependymal zone (SEZ) and neurogenesis in the olfactory bulb decline in the forebrain of telomerase-deficient mice. The present work reveals additional effects of telomere shortening on neuronal differentiation, as adult multipotent progenitors with critically short telomeres yield reduced numbers of neurons that, furthermore, exhibit underdeveloped neuritic arbors. Genetic data indicate that the tumor suppressor protein p53 not only mediates the adverse effects of telomere attrition on proliferation and self-renewal but it is also involved in preventing normal neuronal differentiation of adult progenitors with dysfunctional telomeres. Interestingly, progenitor cells …
Effects of Nrf2 deficiency on bone microarchitecture in an experimental model of osteoporosis
2014
Objective. Redox imbalance contributes to bone fragility. We have evaluated the in vivo role of nuclear factor erythroid derived 2-related factor-2 (Nrf2), an important regulator of cellular responses to oxidative stress, in bone metabolism using a model of postmenopausal osteoporosis. Methods. Ovariectomy was performed in both wild-type and mice deficient in Nrf2 (Nrf2-/-). Bone microarchitecture was analyzed by CT. Serum markers of bone metabolism were also measured. Reactive oxygen species production was determined using dihydrorhodamine 123. Results. Sham-operated or ovariectomized Nrf2 -/- mice exhibit a loss in trabecular bone mineral density in femur, accompanied by a reduction in co…