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91.
Brain-derived heat shock protein 70-peptide complexes induce NK cell-dependent tolerance to experimental autoimmune encephalomyelitis 总被引:1,自引:0,他引:1
Galazka G Stasiolek M Walczak A Jurewicz A Zylicz A Brosnan CF Raine CS Selmaj KW 《Journal of immunology (Baltimore, Md. : 1950)》2006,176(3):1588-1599
Heat shock proteins (Hsp) are markedly up-regulated at sites of inflammation during autoimmune diseases like experimental autoimmune encephalomyelitis (EAE). In this study, we show that Hsp70-peptide complexes (pc) isolated from brains of mice with EAE prevented the development of EAE clinically and pathologically when administered before proteolipid protein 139-151 (PLP139-151) immunization. In contrast, pure Hsp70 or Hsp70-pc derived from brains of healthy mice or other inflamed tissue did not modulate the expression of EAE. In animals in which EAE had been suppressed by Hsp70-pc, lymphocytes showed increased cell death in response to PLP139-151 that correlated with elevated IFN-gamma and NO production. Coculture of spleen cells from Hsp70-pc immunized mice with spleen cells from untreated EAE mice, in addition to depletion experiments, showed that NK cells reduced reactivity to PLP139-151. Transfer of NK cells from Hsp70-pc-immunized mice to recipients sensitized for EAE abolished disease development. Thus, we propose that Hsp70 demonstrate the ability to bind to peptides generated during brain inflammation and to induce a regulatory NK cell population that is capable of preventing subsequent autoimmunization for EAE. 相似文献
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94.
Staphylokinase is a 135 amino acid protein produced by certain strains of Staphylococcus aureus. It belongs to fibrin-specific plasminogen activator. Staphylokinase converts plasminogen--the inactive proenzyme--to the plasmin, which dissolves the fibrin of a blood clots. This review will focus on the biochemical and thrombolytic properties of staphylokinase and its derivatives, which would make use of treatment in acute myocardial infarction and other cardiovascular diseases. 相似文献
95.
In the dog, unlike most other domestic animal species, corpus luteum (CL) life span is not affected by hysterectomy. Only in pregnant dogs, during the immediate prepartum decline of progesterone, does PGF2alpha clearly seem to act as an endogenous luteolytic agent. Whether endogenous PGF2alpha plays a role in the slow regression of the corpora lutea of the nonpregnant cycle is not known. To test for possible paracrine/autocrine effects of locally produced PGF2alpha, luteal expression of the key rate-limiting enzymes in prostaglandin biosynthesis, i.e. cyclooxygenase 1 and 2 (Cox1 and Cox2), was examined in dogs during diestrus, including the periods of CL formation, as well as early and late CL regression. Corpora lutea were collected by ovariohysterectomy from nonpregnant bitches 5, 15, 25, 35, 45 and 65 days after ovulation. On the mRNA-level, expression of Cox1 and Cox2 was tested by qualitative and quantitative, Real Time (Taq Man) RT-PCR; on the protein level, expression of Cox2 was studied by immunohistochemistry. The mRNA for Cox1 and Cox2 were detected at all stages of diestrus. Expression of Cox1 was lowest on Day 5 (ovulation = Day 0) and higher and nearly constant thereafter. Expression of Cox2-mRNA was distinctly cycle related and highest on Day 5; it decreased by Day 15 and remained constantly low until Day 65. Immunohistochemistry localized expression of Cox2 in the cytoplasm of luteal cells. Staining was restricted to Days 5 and 15, with stronger signals on Day 5. These data suggested that increased expression of Cox2 is associated with luteal growth and development and not luteal regression. Furthermore, the expression of Cox1 more likely reflected activity of a housekeeping gene. 相似文献
96.
SDF-1 alone and in co-operation with HGF regulates biology of human cervical carcinoma cells 总被引:2,自引:0,他引:2
Majka M Drukala J Lesko E Wysoczynski M Jenson AB Ratajczak MZ 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2006,44(3):155-164
Stromal Derived Factor-1 (SDF-1)-CXCR4 axis plays a pivotal role in biology and metastasis of several tumors. The aim of this study was to see if SDF-1 alone or in combination with Hepatocyte Growth Factor (HGF) affects biology of human cervical carcinoma (HCC) cells. We found that HCC cell lines investigated in our study highly express CXCR4 on their surface. CXCR4 was also expressed on tumor cells in tissue sections derived from cervical cancer patients. At the same time normal cervical epithelium was negative for CXCR4 expression what suggests a strong correlation between CXCR4 and malignant cell phenotype. Subsequently, we studied a potential role of the SDF-1-CXCR4 axis in HCC and noticed that SDF-1 (i) chemoattracted HCC cells, (ii) enhanced their scattering, (iii) stimulated nuclear localization of beta-catenins and upregulated their target gene cyclin D1 and (iv) at the molecular level induced calcium flux and activated RAS-MAPK, PI3-AKT and JAK-STAT pathways. SDF-1-mediated functions were additionally enhanced in the presence of HGF. Thus, our data show that the SDF-1-CXCR4 axis affects biology of HCC cells. Furthermore, we postulate that this axis might become a potential target to prevent progression of cervical cancer. 相似文献
97.
Comparison of different signal peptides for protein secretion in nonlytic insect cell system 总被引:1,自引:0,他引:1
Protein expression and secretion in insect cells have been widely studied in the baculovirus-infected insect cell system. In directly transfected insect cells only intracellular expression and purification of recombinant proteins have been studied in detail. To examine multiple recombinant protein variants, easy and fast expression and a purification screening system are required. The aim of this study was to establish an effective and rapid secretion system for human azurocidin using directly transfected insect cells. We also constructed and tested expression vectors possessing heterologous signal peptides derived from human azurocidin, yellow lupin diphosphonucleotide phosphatase/phosphodiesterase (PPD1), and papaya papain IV to secrete yellow lupin and red kidney bean purple acid phosphatases, PPD1, and papain IV. Our results demonstrate that the secretion vectors used here can direct recombinant proteins to the culture medium very effectively, allowing their simple purification on a small/medium scale. Based on secretion and activity analyses it seems that the azurocidin signal peptide is one of the most potent secretion signals. 相似文献
98.
The aim of this study was to look at basic endocrinological disorders in chronic kidney disease, acquainting endocrinologists with information about the definition and classification of kidney diseases and basic metabolic disorders in uraemia. Secondary hyperparathyroidism, insulin resistance and hyperinsulinism, growth hormone disorders and the possibility of growth hormone treatment, the reasons for and the consequences of hyperprolactinaemia are presented in a practical way. Thyroid hormones management, a problem which requires further study, is portrayed extensively. Hypothalamic-pituitary-adrenal axis disorders are equally complex and not yet fully examined. We have largely concentrated on the practical aspects of diagnostics of the presented disorders. 相似文献
99.
Piotrowski P Lianeri M Wudarski M Olesińska M Jagodziński PP 《Molecular biology reports》2012,39(9):8861-8866
The STAT4 has been found to be a susceptible gene in the development of systemic lupus erythematosus (SLE) in various populations. There are evident population differences in the context of clinical manifestations of SLE, therefore we investigated the prevalence of the STAT4 G > C (rs7582694) polymorphism in patients with SLE (n = 253) and controls (n = 521) in a sample of the Polish population. We found that patients with the STAT4 C/G and CC genotypes exhibited a 1.583-fold increased risk of SLE incidence (95 % CI = 1.168-2.145, p = 0.003), with OR for the C/C versus C/G and G/G genotypes was 1.967 (95 % CI = 1.152-3.358, p = 0.0119). The OR for the STAT4 C allele frequency showed a 1.539-fold increased risk of SLE (95 % CI = 1.209-1.959, p = 0.0004). We also observed an increased frequency of STAT4 C/C and C/G genotypes in SLE patients with renal symptoms OR = 2.259 (1.365-3.738, p = 0.0014), (p (corr) = 0.0238) and in SLE patients with neurologic manifestations OR = 2.867 (1.467-5.604, p = 0.0016), (p (corr) = 0.0272). Moreover, we found a contribution of STAT4 C/C and C/G genotypes to the presence of the anti-snRNP Ab OR = 3.237 (1.667-6.288, p = 0.0003), (p (corr) = 0.0051) and the presence of the anti-Scl-70 Ab OR = 2.665 (1.380-5.147, p = 0.0028), (p (corr) = 0.0476). Our studies confirmed an association of the STAT4 C (rs7582694) variant with the development of SLE and occurrence of some clinical manifestations of the disease. 相似文献