Search results for "differentiation"

Perlecan Maintains microvessel integrity in vivo and modulates their formation in vitro

2012

Perlecan is a heparan sulfate proteoglycan assembled into the vascular basement membranes (BMs) during vasculogenesis. In the present study we have investigated vessel formation in mice, teratomas and embryoid bodies (EBs) in the absence of perlecan. We found that perlecan was dispensable for blood vessel formation and maturation until embryonic day (E) 12.5. At later stages of development 40% of mutant embryos showed dilated microvessels in brain and skin, which ruptured and led to severe bleedings. Surprisingly, teratomas derived from perlecan-null ES cells showed efficient contribution of perlecan-deficient endothelial cells to an apparently normal tumor vasculature. However, in perlecan…

Prestress in the extracellular matrix sensitizes latent TGF-β1 for activation

2014

A mild strain induced by matrix remodeling mechanically primes latent TGF-β1 for its subsequent activation and release in response to contractile forces.

α5β1 integrin-mediated adhesion to fibronectin is required for axis elongation and somitogenesis in mice.

2011

The arginine-glycine-aspartate (RGD) motif in fibronectin (FN) represents the major binding site for α5β1 and αvβ3 integrins. Mice lacking a functional RGD motif in FN (FN(RGE/RGE)) or α5 integrin develop identical phenotypes characterized by embryonic lethality and a severely shortened posterior trunk with kinked neural tubes. Here we show that the FN(RGE/RGE) embryos arrest both segmentation and axis elongation. The arrest is evident at about E9.0, corresponding to a stage when gastrulation ceases and the tail bud-derived presomitic mesoderm (PSM) induces α5 integrin expression and assumes axis elongation. At this stage cells of the posterior part of the PSM in wild type embryos are tight…

β1D Integrin Inhibits Cell Cycle Progression in Normal Myoblasts and Fibroblasts

1998

Integrins are alphabeta heterodimeric transmembrane receptors involved in the regulation of cell growth and differentiation. The beta1 integrin subunit is widely expressed in vivo and is represented by four alternatively spliced cytoplasmic domain isoforms. beta1D is a muscle-specific variant of beta1 integrin and a predominant beta1 isoform in striated muscles. In the present study we showed that expression of the exogenous beta1D integrin in C2C12 myoblasts and NIH 3T3 or REF 52 fibroblasts inhibited cell proliferation. Unlike the case of the common beta1A isoform, adhesion of beta1D-transfected C2C12 myoblasts specifically via the expressed integrin did not activate mitogen-activated pro…

Induction of interferon regulatory factors, 2′‐5′ oligoadenylate synthetase, P68 kinase and RNase L in chronic myelogenous leukaemia cells and its re…

1996

The genes crucially determining the therapeutic response of chronic myelogenous leukaemia (CML) to interferon-alpha (IFN-alpha) are unknown. Recently, two independent IFN-alpha signalling pathways were identified: the classic pathway mediates induction of 2'-5' oligoadenylate synthetase (2-5 OAS), p68 kinase and IFN regulatory factor-2 (IRF-2), whereas the alternate pathway leads to activation of IFN regulatory factor-1 (IRF-1). We investigated whether deficient or imbalanced expression of components of these two pathways is associated with resistance of CML cells to antiproliferative action of IFN alpha/beta. Constitutive and IFN-induced transcript levels of IFN-dependent genes in mononucl…

Cloned T helper cells reverting to a resting state develop increasing sensitivity in their antigen-mediated interaction with accessory cells.

1988

A cloned murine T cell line, KIII5, specific for the polypeptide poly-L(Tyr,Glu)-poly-D,L-Ala--poly-L-Lys [(T,G)-A--L] was compared at different stages after antigenic stimulation with respect to the conditions required for the reinduction of growth by varying concentrations of antigen presented on different types of accessory cells (AC). We show that the dose of antigen necessary for inducing half maximal proliferation in the presence of splenic AC shifts to considerably lower concentrations when the T cell blasts revert to a resting state (100 micrograms/ml on day 7 to 10 micrograms/ml on day 21-35). During the same time period the expression of interleukin 2 (IL2) receptor and the reacti…

Human interleukin 2: molecular biology, physiology and clinical possibilities.

1986

Interleukin-12 and -23 Control Plasticity of CD127(+) Group 1 and Group 3 Innate Lymphoid Cells in the Intestinal Lamina Propria.

2015

Human group 1 ILCs consist of at least three phenotypically distinct subsets, including NK cells, CD127(+) ILC1, and intraepithelial CD103(+) ILC1. In inflamed intestinal tissues from Crohn's disease patients, numbers of CD127(+) ILC1 increased at the cost of ILC3. Here we found that differentiation of ILC3 to CD127(+) ILC1 is reversible in vitro and in vivo. CD127(+) ILC1 differentiated to ILC3 in the presence of interleukin-2 (IL-2), IL-23, and IL-1β dependent on the transcription factor RORγt, and this process was enhanced in the presence of retinoic acid. Furthermore, we observed in resection specimen from Crohn's disease patients a higher proportion of CD14(+) dendritic cells (DC), whi…

PSA-NCAM is expressed in immature, but not recently generated, neurons in the adult cat cerebral cortex layer II

2011

Neuronal production persists during adulthood in the dentate gyrus and the olfactory bulb, where substantial numbers of immature neurons can be found. These cells can also be found in the paleocortex layer II of adult rodents, but in this case most of them have been generated during embryogenesis. Recent reports have described the presence of similar cells, with a wider distribution, in the cerebral cortex of adult cats and primates and have suggested that they may develop into interneurons. The objective of this study is to verify this hypothesis and to explore the origin of these immature neurons in adult cats. We have analyzed their distribution using immunohistochemical analysis of the …

Argentum-quarz solution in the treatment of anorectal fistulas: Is it possible a conservative approach?

2012

Patients suffering from chronic intestinal diseases (Crohn's disease, Ulcerative Colitis, Indeterminate Colitis) are prone to the development of pyogenic complications. These complications are most commonly in the form of perianal or intraabdominal abscesses and/or fistulas. The treatment of these complications are managed differently but, after an initial treatment based on medical or minimally invasive management, the solution of the pathological condition is always achieved by a surgical procedure. In the last few years prospective studies have proposed an alternative conservative therapeutic approach based on application of fibrin glue in the healing of patients with fistulas-in-ano. In…