Search results for "Cytotoxic"

New Alkenylresorcinols with Cytotoxic and Antimicrobial Activities from the Leaves of Embelia schimperi.

2020

AbstractA phytochemical study of the methanol extract of the leaves of Embelia schimperi resulted in the isolation of three new alkenylresorcinols, 1 – 3, together with the known analogs 4 – 7. Their structures were established by a combination of spectroscopic techniques. Compounds 1 – 7 exhibited moderate cytotoxic activity against human cervical cancer cells HeLa-S3 and more pronounced antimicrobial properties towards bacteria and filamentous fungi. The present study falls into an ongoing research project on the characterization of bioactive phenolic lipids from plants of the family Primulaceae.

Smad7 in T cells drives T helper 1 responses in multiple sclerosis and experimental autoimmune encephalomyelitis

2010

Autoreactive CD4+ T lymphocytes play a vital role in the pathogenesis of multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis. Since the discovery of T helper 17 cells, there is an ongoing debate whether T helper 1, T helper 17 or both subtypes of T lymphocytes are important for the initiation of autoimmune neuroinflammation. We examined peripheral blood CD4+ cells from patients with active and stable relapsing-remitting multiple sclerosis, and used mice with conditional deletion or over-expression of the transforming growth factor-beta inhibitor Smad7, to delineate the role of Smad7 in T cell differentiation and autoimmune neuroinflammation. We found that Smad…

Inhibition of the mixed lymphocyte reaction by T cell vaccination

1990

Immunization with attenuated activated autoreactive T cell lines and clones induces a response in syngeneic animals which can induce protection or recovery from autoimmune disease. This process has been termed T cell vaccination. The aim of the present study was to investigate the effect of immunization with MHC-reactive T cells on the mixed lymphocyte reaction (MLR). By injecting attenuated activated T cells primed for an alloantigen, we markedly reduced the MLR in both rats and mice. This depression appeared to be mediated by active suppression; lymphoid cells from T cell-vaccinated animals suppressed the MLR responsiveness of T cells from naive animals. Suppression of the MLR was not res…

IL-6 controls Th17 immunity in vivo by inhibiting the conversion of conventional T cells into Foxp3+regulatory T cells

2008

The conditions leading to the induction of adaptive Foxp3+regulatory T cells (T-regs) from peripheral T cells in vivo are incompletely understood. Here, we show that unresponsiveness of T cells to IL-6 by T cell-selective deletion of gp130 or immunization of wild-type mice with antigen in incomplete Freund's adjuvant (IFA), which fails to induce IL-6, promotes the conversion of peripheral CD4+T cells into adaptive Foxp3+T-regs. Thus, both T cell-conditional gp130 knockout (KO) mice immunized with MOG35-55 in complete Freund's adjuvant (CFA) and wild-type mice immunized with MOG35-55 in IFA develop overwhelming antigen-specific T-reg responses and are protected from experimental autoimmune e…

TGF-beta as a T cell regulator in colitis and colon cancer

2005

TGF-beta is a pleiotropic cytokine with powerful immunosuppressive functions. Mice deficient for TGF-beta1 show a dramatic phenotype with severe multiorgan inflammation and die shortly after birth. Recent investigations have highlighted the role of TGF-beta in suppression of T cell mediated autoimmune inflammation and anti-tumor immunity. In addition to its direct anti-inflammatory effects on T cells, TGF-beta has been implicated as central regulator of regulatory T cells. TGF-beta not only mediates the suppression of effector T cells by Tregs, recent evidence also reveals a role for TGF-beta along with TCR stimulation in the peripheral induction of regulatory T cells from naïve CD4+CD25- c…

Impact of Ceramic and Metallic Nano-scaled Particles on Endothelial Cell Functionsin vitro

2007

The sections in this article are Introduction Origin of Particles in the Human Environment Evidence for Size-dependent Toxicity of Particles Dissemination and Interferences of Nanoparticles within the Body Endothelial Cells and Nanoparticle Exposure Testing of Nanoparticle-induced Effects on Human Endothelial Cells In Vitro Materials and Methods Cell Culture Particles Transmission Electron Microscopy (TEM) Cytotoxicity Assay Detection of Ki67 Expression Quantification of IL-8 Release in Cell Culture Supernatant Quantification of E-selectin Cell Surface Protein Expression Fluorescence Staining Statistical Analysis Results Discussion Particle Internalization Particle Cytotoxicity Pro-inflamma…

Failure of Cytomegalovirus-Specific CD8+ T Cell Levels at Viral DNAemia Onset to Predict the Eventual Need for Preemptive Antiviral Therapy in Alloge…

2018

Colorectal cancer defeating? Challenge accepted!

2013

Colorectal tumours are actually considered as aberrant organs, within it is possible to notice a different stage of cell growth and differentiation. Their origin is reported to arise from a subpopulation of tumour cells endowed with, just like the healthy stem cells, self-renewal and aberrant multi-lineage differentiation capacity likely to be called colorectal cancer stem cells (CCSCs). Cancer stem cells (CSCs) fate, since their origin, reflects the influences from their microenvironment (or niche) both in the maintenance of stemness, in promoting their differentiation, and in inducing epithelial-mesenchymal transition, responsible of CSCs dissemination and subsequent formation of metastat…

Fully synthetic self-adjuvanting thioether-conjugated glycopeptide-lipopeptide antitumor vaccines for the induction of complement-dependent cytotoxic…

2012

Glycopeptides of tumor-associated mucin MUC1 are promising target structures for the development of antitumor vaccines. Because these endogenous structures were weakly immunogenic, they were coupled to immune-response-stimulating T-cell epitopes and the Pam(3)Cys lipopeptide to induce strong immune responses in mice. A new thioether-ligation method for the synthesis of two- and three-component vaccines that contain MUC1 glycopeptides as the B-cell epitopes, a T-cell epitope peptide, and the Pam(3)CSK(4) lipopeptide is described. The resulting fully synthetic vaccines were used for the vaccination of mice, either in a liposome with Freund's adjuvant or in aqueous PBS buffer. The three-compon…

Frequency of CD8+ T Lymphocytes Specific for Lytic and Latent Antigens of Epstein–Barr Virus in Healthy Virus Carriers

1999

Abstract We investigated CD8 + T cell frequencies of five different Epstein–Barr virus-specific cytotoxic T lymphocyte epitopes located within proteins of the replicative cycle and the latent state in healthy long-term virus carriers with IFN-γ enzyme-linked immunospot assay. Frequencies of the HLA-A3-restricted epitope RVRAYTYSK (RVR) whose minimal length was mapped in this study to amino acid position 148–156 of the immediate-early protein BRLF1 were compared with those of a further known HLA-A3-restricted epitope within EBNA3A, RLRAEAQVK (RLR). Determination of frequencies of CD8 + T lymphocytes directed against lytic antigen epitope RVR revealed that only one of eight donors recognized …