Search results for "rats"
showing 10 items of 3537 documents
Lymphocytes from hepatic inflammatory infiltrate kill rat hepatocytes in primary culture
1990
In the last few years it has become possible in the liver to isolate lymphocytes from inflammatory infiltrates and to culture them in vitro. Most of the lymphocyte clones obtained are CD 8 + cytotoxic cells, but interactions between these lymphocytes and hepatocytes in primary culture have not been analysed previously. In this study, cloned human T lymphocytes from liver biopsies and from the peripheral blood of patients with chronic hepatitis B or primary biliary cirrhosis, after phenotypical and functional characterization into CD 8+ or CD 4+ cytotoxic lymphocytes, were activated in an antigen-independent fashion by adding either anti CD 3 or anti CD 2/R-3 monoclonal antibodies to the cel…
Identification and characterization of a monoclonal antibody to the membrane fatty acid binding protein
1992
A monoclonal antibody to the rat liver membrane fatty acid binding protein (MFABP) was prepared by immunizing mice with purified MFABP isolated from solubilized rat liver plasma membrane proteins by oleate-agarose affinity chromatography technique. The monoclonal antibody K15/6 identified a single 40 kDa protein in rat liver plasma membranes with pI values of 8.5, 8.8 and 9.0, which is identical to the authentic MFABP, but clearly distinct from rat mitochondrial GOT. The antibody K15/6 selectively inhibited cellular influx as well as membrane binding of fatty acids, but not of cholesterol or vitamin E. The same antibody was used in immunofluorescence, ELISA and Western blot analysis to dete…
Carcinogenic aspect of xenobiotic molecules belonging to the peroxisome proliferator family.
1999
It is known that a short-term exposure of rat, mice or incubation of hepatic cells with fibrate molecules leads to increase in peroxisome number and cell hyperplasia. Further, long-term incubation of cells (at least a year) show transformed characteristics with foci and nodules. To explain the hepatocarcinogenic effect of peroxisome proliferators in rodents we studied the effect of peroxisome proliferators on rat liver oncogenes expression. Earlier, we reported an increase in liver and kidney mRNA level of c-myc and N-myc. Since several metabolic genes are activated by PPAR (peroxisome proliferators activated receptor) through a PPRE (peroxisome proliferator response element), we suggest th…
Geranylgeranyl as well as farnesyl moiety is transferred to Ras p21 overproduced in adrenocortical cells transformed by c-Ha-rasEJ oncogene.
1997
The ras-transformed newborn rat adrenocortical (RTAC) cells were obtained by transfection with the mutated c-Ha-rasEJ oncogene. They are proliferative and tumorigenic cells characterized by expression of the c-Ha-rasEJ oncogene and overexpression of a wild-type ras oncogene. The overproduced Ras p21 was identified here as Ki-Ras p21 by western blotting using a specific anti-Ki-Ras monoclonal antibody. Radioactivity derived from [14C]mevalonolactone was strongly incorporated into Ras p21 overproduced in RTAC cells. RTAC cells pretreated with lovastatin and labeled with either [3H]geranylgeranyl-pyrophosphate or [3H]farnesyl-pyrophosphate incorporated also radioactivity into Ras p21. These re…
Anti-inflammatory activity of two cucurbitacins isolated from Cayaponia tayuya roots.
2004
Fractionation of an anti-inflammatory extract from Cayaponia tayuya roots yielded two active compounds, identified as 23,24-dihydrocucurbitacin B (1) and cucurbitacin R (2). Both were evaluated for their anti-inflammatory activity on several experimental models of pain and inflammation. In addition, their cytotoxicity and effects on leukotriene B 4 (LTB 4 ) formation were evaluated in rat polymorphonuclear leukocytes. Both compounds showed activity in the following models: carrageenan-induced mouse paw oedema (1, 4 mg/kg p.o., 46% inhibition at 3 h), phospholipase A 2 -induced mouse paw oedema (2, 3 mg/kg i.p., 61% inhibition at 60 min), serotonin-induced mouse paw oedema (1 and 2, 0.5 mg/k…
Anti-inflammatory activity of 5-O-demethylnobiletin, a polymethoxyflavone isolated from Sideritis tragoriganum.
2006
We have studied the effect of 5- O-demethylnobiletin ( 1) on both the inflammation of mouse ears induced by repeated application of 12- O-tetradecanoylphorbol 13-acetate (TPA) and the acute mouse paw oedemas induced by carrageenan and phospholipase A (2) (PLA (2)), and determined its activity on 5-lipoxygenase (5-LOX) and elastase release/activity. Compound 1 reduced the oedema formation, cell infiltration, and tissue damage in the inflammation induced by TPA in mouse ears, along with the acute oedema induced by carrageenan in mouse paws and the acute PLA (2)-induced oedema in mouse paws. The flavone inhibited leukotriene B (4) formation in rat neutrophils and elastase release in human neut…
Preparation of a dansylated fibrate, a new fluorescent tool to study peroxisome proliferation. Effect on hepatic-derived cell lines.
1997
The synthesis of a dansylated fibrate (DNS-X) has been performed in order to identify the cellular affinity sites of peroxisome proliferators and to establish the subcellular localization of such molecules. DNS-X has been obtained by coupling the dansy1 chloride with the amine resulting from the bezafibrate alkaline hydrolysis. The purified DNS-X has been further characterized by spectrum analysis (UV-Vis, fluorescence, [1H]/[13C]-NMR and mass). At 250 microM and incubated for 48 h with the rat hepatic derived cells (Fao cells), DNS-X stimulates 12-fold the palmitoyl-CoA oxidase, a peroxisome proliferation marker enzyme. This increase is comparable to the one obtained with well known peroxi…
Activation of a murine autoreactive B cell by immunization with human recombinant autoantigen La/SS-B: Characterization of the autoepitope
1995
Immunization of Balb/c mice with a homogeneously purified recombinant human La/SS-B protein resulted in activation of an autoreactive B cell secreting a novel monoclonal anti-La antibody termed La4B6. La4B6 reacted with La protein from a variety of sources including human, bovine, rat and mouse. ATP blocked the binding of La4B6 to recombinant La protein. The human epitope was identified as consisting of the amino acid sequence SKGRRFKGKGKGN, which includes the proposed ATP-binding site of the La protein. In the human and bovine La protein, the epitope exists as a continuous amino acid sequence. In rat and mouse the epitope was found to consist of the amino acid sequence SKG interrupted by a…
Injection of Donor-Derived OX62+ Splenic Dendritic Cells With Anti-CD4 Monoclonal Antibody Generates CD4+CD25+FOXP3+ Regulatory T Cells That Prolong …
2009
Abstract Objective To examine in a rat model the ability of donor dendritic cells and anti-CD4 monoclonal antibody (mAb) to generate donor-specific CD4+CD25+ regulatory T cells (Tregs) and to evaluate the capacity of these Tregs to prolong skin allograft survival and abrogate the production of donor-specific antibodies after skin grafting. Materials and Methods OX62+ (nonplasmacytoid) splenic dendritic cells were isolated from Fischer rats using magnetic beads and injected (2 × 10 6 ) into Lewis rat recipients with or without treatment with a nondepleting anti-CD4 (W3/25) mAb. After 4 weeks, splenic CD4+CD25+FOXP3+ T cells were harvested using magnetic beads from conditioned animals and inj…
Adrenergic modulation of astroglial phospholipase D activity and cell proliferation.
1999
As phospholipase D (PLD) activation has been associated with mitogenic signalling in several cell types, we tested an association between adrenergic activation of PLD and cellular proliferation in primary cultures of rat cortical astrocytes. In 2-week old cultures, PLD activation by noradrenaline (EC50: 0.49 microM) was inhibited by prazosin, a specific antagonist at alpha1-adrenergic receptors (IC50: 0.23 microM). Adrenergic PLD activation was not affected by genistein, an inhibitor of tyrosine kinases, or by Ro 31-8220, an inhibitor of protein kinase C (PKC), but was dose-dependently depressed in the presence of brefeldin A (1-100 microg/ml), an inhibitor of ARF activation. In experiments…