Search results for "Hsp"
showing 10 items of 557 documents
Different Efficiency of Heat Shock Proteins (HSP) to Activate Human Monocytes and Dendritic Cells: Superiority of HSP60
2002
Abstract One essential immunoregulatory function of heat shock protein (HSP) is activation of the innate immune system. We investigated the activation of human monocytes and monocyte-derived dendritic cells (DC) by recombinant human HSP60, human inducible HSP72, and preparations of human gp96 and HSP70 under stringent conditions, in the absence of serum and with highly purified monocytes. HSP60 induced human DC maturation and activated human DC to secrete proinflammatory cytokines. HSP72 induced DC maturation to a lesser extent, but activated human monocytes and immature DC as efficiently as HSP60 to release proinflammatory cytokines. The independence of the effects of HSP60 and HSP72 from …
Toxicological assessment of mesoporous silica particles in the nematode Caenorhabditis elegans
2018
[EN] Here we report the toxicological evaluation of mesoporous silica particles (MSPs) in the nematode C. elegans. Specifically, we have investigated the effect of bare micro- (M0) and nano-sized (N0) MSPs, and their corresponding functionalized particles with a starch derivative (Glu-N) (M1 and N1, respectively) on C. elegans ageing parameters. The toxicity of MSPs, their impact on C. elegans lifespan, movement capacity, progeny and ability to survive upon exposure to acute oxidative stress were assessed. This study demonstrated that both size particles assayed (M0 and N0), labeled with rhodamine and monitored through fluorescence microscopy, are ingested by the nematode. Moreover, toxicit…
Association between Serum Heat Shock Proteins and Gamma-Delta T Cells—An Outdated Clue or a New Direction in Searching for an Anticancer Strategy? A …
2021
HSPs demonstrate a strong association with gamma-delta (γδ) T cells. Most of the studies regarding interactions between the parameters were conducted in the 1990s. Despite promising results, the concept of targeting γδ T cells by HSPs seems to be a forgotten direction due to potent non-peptidic phosphoantigens rather than HSPs have been found to be the essential stimulatory components for human γδ cells. Currently, with greater knowledge of lymphocyte diversity, and more accurate diagnostic methods, we decided to study the correlation once again in the neoplastic condition. Twenty-one children with newly diagnosed acute lymphoblastic leukaemia (ALL) were enrolled on the study. Serum HSP90 c…
Modulation of 2′-5′oligoadenylate synthetase by environmental stress in the marine spongeGeodia cydonium
1997
Recently we established the presence of relatively high amounts of 2′-5′oligoadenylates (2′-5′A) and 2′-5′oligoadenylate synthetase (2′-5′A synthetase) in the marine sponge Geodia cydonium. Here we determined by applying radioimmunoassay and high-performance liquid chromatographical methods that the concentration of 2′-5′A and the activity of 2′-5′A synthetase change following exposure of G. cydonium tissue to environmental stress. The 2′-5′A content and the activity of 2′-5′A synthetase, present in crude sponge extract, increase by up to three-fold after treating sponge cubes for 2 h with natural stressors including heat shock (26°C), cold shock (6°C), pH shock (pH 6), and hypertonic shock…
Discovery and validation of small-molecule heat-shock protein 90 inhibitors through multimodality molecular imaging in living subjects.
2012
Up-regulation of the folding machinery of the heat-shock protein 90 (Hsp90) chaperone protein is crucial for cancer progression. The two Hsp90 isoforms (α and β) play different roles in response to chemotherapy. To identify isoform-selective inhibitors of Hsp90(α/β)/cochaperone p23 interactions, we developed a dual-luciferase (Renilla and Firefly) reporter system for high-throughput screening (HTS) and monitoring the efficacy of Hsp90 inhibitors in cell culture and live mice. HTS of a 30,176 small-molecule chemical library in cell culture identified a compound, N -(5-methylisoxazol-3-yl)-2-[4-(thiophen-2-yl)-6-(trifluoromethyl)pyrimidin-2-ylthio]acetamide (CP9), that binds to Hsp90(α/β) an…
Cadmium regulation of apoptotic and stress response genes in tumoral and immortalized epithelial cells of the human breast
2008
Cadmium (Cd) is a widely-disseminated metal which can be imported and accumulated in living cells thereby drastically interfering with their biological mechanisms. Increasing interest has been recently focused on the elucidation of the cellular and molecular aspects of Cd-dependent regulation of gene expression and signal transduction pathways in different model system. Concerning breast cancer, very limited studies have been produced so far on the role played by Cd on estrogen receptor-negative human breast cancer cells, that are expected to be insensitive to the already-proven metallo-estrogenic effect exerted by Cd on the estrogen receptor-positive cell counterparts. Here, we have examin…
Constitutive hsp70 is essential to mitosis during early cleavage of Paracentrotus lividus embryos: The blockage of constitutive hsp70 impairs mitosis
1999
Localization of constitutive hsp70 in eggs and early embryos of sea urchin Paracentrotus lividus is shown by means of in situ immunostaining. An accumulation of this protein is shown in the mitotic structures (asters, spindles and centrosomes). Microinjection of anti-hsp70 antibodies into eggs causes impairment of formation of mitotic structures and of cell division. This impairment goes from a complete mitotic block, to irregular mitotic apparatus formation with irregular cleavage, depending upon the antibody concentration. The localization of hsp70 after antibody microinjection is also described. Blockage of mitotic apparatus formation by nocodazole also blocks the concentration of hsp70 …
Coelomocytes and post-traumatic response in the common sea star Asterias rubens.
2008
Coelomocytes are recognized as the main cellular component of the echinoderm immune system. They are the first line of defense and their number and type can vary dramatically during infections or following injury. Sea stars have been used as a model system to study the regeneration process after autotomy or predation. In the present study we examined the cellular and biochemical responses of coelomocytes from the European sea star Asterias rubens to traumatic stress using immunochemical and biochemical approaches. In terms of trauma and post-traumatic stress period, here we consider the experimental arm amputation and the repair phase involved in the first 24 hours post-amputation, which mi…
Adhesion and adaptive response of osteoblastlike cells (SAOS-2) grown on dfferent ti-6al-4v surfaces.
2004
Osteoblastic-like cells (SAOS-2) were seeded on three differently treated surfaces of Ti- 6Al-4V (T1: not treated; T2: chemically treated; T3: electrochemically treated). After 6h, the cells grown on T1 and T2 surfaces showed a typical poligonal morphology, they were strongly adherent to the surface and after 24h-48h they spread and formed a confluent monolayer. On the contrary, cells seeded on T3 showed heterogeneous morphology, decreased adhesion, loss of thin cellular expansions, and showed cellular shrinkage and apoptotic blebbing; only after 48h they were able to attach and form a monolayer after 4 days of seeding. Cell proliferation was significantly lower on T3 than T1 and T2 surface…
Adaptive response of osteoblasts grown on a titanium surface: morphology, cell proliferation and stress protein synthesis.
2005
Titanium is one of the most widely used biomaterials in orthopaedic, dental and trauma surgery. Superficial adhesion and cell proliferation represent the first steps of cell-biomaterial interactions. The efficacy of this early phase influences the subsequent ability to differentiate, and hence the knowledge of these cell activities is important for studying and improving the biocompatibility of biomaterials. The aim of this study was to test the adaptive ability of osteoblastic cells grown on titanium surfaces, including morphologic, proliferative and adaptative aspects.