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1.
Adenovirus-mediated gene transfer into the brain is associated with significant inflammation and activation of anti-vector and anti-transgene immune responses that curtail the gene delivery of adenoviruses and therapeutic efficacy. Elucidating the molecular mediators of inflammatory and immune responses to adenoviruses injected into the brain should allow us to inhibit their inflammatory actions, thereby reducing vector clearance and enhance adenoviral-mediated gene transfer into the CNS. Cytokines are primary mediators of the immune response and are released during inflammation. Here we report for the first time that injection of replication-deficient adenovirus vectors into the cerebral ventricles of rats causes a rapid increase in body temperature. This fever response precedes any vector-encoded transgene expression and occurs with vectors encoding no transgene, as well as with vectors encoding a therapeutic transgene i.e., HSV1-thymidine kinase. No fever is detected after infection of the striatum, an important brain target in studies on neurodegeneration. After infection of the brain ventricles, CSF levels of immunoreactive tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta increase significantly (up to 300-fold). In the hypothalamus, the locus of thermoregulation in the brain, only IL-1beta and IL-6 are significantly elevated. A neutralizing TNF-alpha antibody has no effect on adenovirus-induced fever. However, pretreatment with either the IL-1 receptor antagonist or the cyclooxygenase inhibitor flurbiprofen completely abolishes adenovirus-induced fever, suggesting that IL-1 and prostaglandins are direct mediators of this response. These results are the first to demonstrate that IL-1, but not TNF-alpha, is the main mediator of a very early inflammatory response to adenovirus in the brain.  相似文献   

2.
A polymerase chain reaction test for the detection of ovine herpesvirus-2 (OHV-2) DNA was used to identify sites of OHV-2 infection in peri-natal lambs and in adult sheep. OHV-2 was detected in the nasal secretions from all lambs within a period of two months following birth. Subsequently, OHV-2 DNA was identified in a number of epithelial tissues including the cornea, turbinates and pharynx. In addition, OHV-2 DNA was detected exclusively in B-lymphocytes from six of ten adult sheep tested. An infection cycle for OHV-2 in sheep is proposed which bears similarities with the gammaherpesviruses Epstein-Barr virus and mouse herpesvirus-68.  相似文献   

3.
A child had essentially her entire lip and most of her nose bitten off in one piece by a dog. This was replanted by microvascular anastomoses. Most of the fragment survived.  相似文献   

4.
5.
Recombinant ovine interleukin-5 (rovIL-5) expressed from Chinese hamster ovary (CHO) cells was tested for cell-specific bioreactivity, in vitro, in a soft agar clonogenic assay and in an enzyme-based microassay for eosinophil potentiating activity (EPA). In soft agar assays, colony and cluster formation from sheep bone marrow cells (SBMC) incubated with rovIL-5 was significantly enhanced compared with SBMC incubated with control supernatants from mock-transfected CHO cells. Colony analysis at 14 days demonstrated that for three separate rovIL-5 preparations 45%, 61% and 66% of colonies were eosinophilic, as were 55%-71% of clusters. In contrast, no eosinophil colonies were detected in parallel control cultures. RovIL-5 was also shown to possess potent and dose-responsive EPA, on the basis of eosinophil peroxidase (EPO) and arylsulphatase (EAS) assay in 7 day SBMC cultures. This activity was inhibited in a dose-responsive manner by TRFK-5, a rat anti-murine IL-5 monoclonal antibody (MAb) previously shown to have cross-reactivity in the ovine EPA assay. The results demonstrate that rovIL-5 exhibited eosinophil-specific properties similar to those of IL-5 derived from other mammalian species.  相似文献   

6.
Metallurgical and Materials Transactions B - The effect of the surface tension–viscosity dissipation driving liquid Ti flow into a B4C packed bed was analyzed at 1941 K and 2573 K. The model...  相似文献   

7.
Biological activities of C5a and C5adesArg from hog serum   总被引:1,自引:0,他引:1  
The complement-derived peptides C5a and C5adesArg (highly purified from yeast-activated hog serum) were both active in the following biological assays: in aggregation of human leukocytes (potency ratio for C5a:C5adesArg 3:1), in aggregation of guinea pig platelets (10:1), in chemotaxis of peritoneal rabbit leukocytes (10:1), and in contraction of isolated guinea pig ileum (1.4:1). The fact that C5adesArg preparations have 30 and 40% of the activity of C5a in leukocyte aggregation and smooth muscle contraction but only 10% of C5a chemotactic activity, clearly indicates that aggregation and spasmogenic activity are inherent properties of C5adesArg. Evidence that C5adesArg owns all activities studied is further given by the following findings: chromatographic separation of mixtures of C5a and C5adesArg results in the appearance of two peaks of spasmogenic activity; treatment of C5adesArg with carbopeptidase B does neither lead to release of detectable arginine nor abrogate any of the biological effects; treatment of C5a with carboxypeptidase B reduces the activities quantitatively to those of C5adesArg, and liberates the theoretically expected amount of arginine.  相似文献   

8.
The functions of the C5a anaphylatoxin are expressed through its interaction with a cell-surface receptor with seven transmembrane helices. The interaction of C5a with the receptor has been explained by a two-site model whereby recognition and effector sites on C5a bind, respectively, to recognition and effector domains on the receptor, leading to receptor activation (Chenoweth, D. E., and Hugli, T. E. (1980) Mol. Immunol. 17, 151-161. In addition, the extracellular N-terminal region of the C5a receptor has been implicated as the recognition domain for C5a, responsible for approximately 50% of the binding energy of the C5a-receptor complex (Mery, L., and Boulay, F. (1994) J. Biol. Chem. 269, 3457-3463; DeMartino, J. A., Van Riper, G., Siciliano, S. J., Molineaux, C. J., Konteatis, Z. D., Rosen, H., and Springer, M. S. (1994) J. Biol. Chem. 269, 14446-14450). In this work, the interactions of C5a with the N-terminal domain of the C5a receptor were examined by use of recombinant human C5a molecules and peptide fragments M1NSFN5YTTPD10YGHYD15DKDTL20DLNTP25VDKTS30NTLR(hC5aRF-1-34), acetyl-HYD15DKDTL20DLNTP25VDKTS30NTLR (hC5aRF-13-34), and acetyl-TL20DLNTP25VDKTS30N-amide (hC5aRF-19-31) derived from human C5a receptor. Binding induced resonance perturbations in the NMR spectra of the receptor fragments and the C5a molecules indicated that the isolated Nterminal domain or residues 1-34 of the C5a receptor retain specific binding to C5a and to a C5a analog devoid of the agonistic C-terminal tail in the intact C5a. Residues of C5a perturbed by the binding of the receptor peptides are localized within the helical core of the C5a structure, in agreement with the results from functional studies employing mutated C5a and intact receptor molecules. All three receptor peptides, hC5aRF-1-34, hC5aRF-13-34, and hC5aRF-19-31, responded to the binding of C5a through the 21-30 region containing either hydrophobic, polar, or positively charged residues such as Thr24, Pro25, Val26, Lys28, Thr29, and Ser30. The 21-30 segment of all three receptor fragments was found to have a partially folded conformation in solution, independent of residues 1-18. These results indicate that a short peptide sequence, or residues 21-30, of the C5a receptor N terminus may constitute the binding domain for the recognition site on C5a.  相似文献   

9.
The surgical management of tetralogy of Fallot has undergone important changes in recent years. Earlier repair of tetralogy of Fallot is now favored by many institutions. At Stanford University Medical Center, we have performed definitive repair of tetralogy of Fallot at the time of presentation, regardless of the child's age, with few exceptions. In this report, we describe our results with early repair, and we believe these support the contention that infants who undergo early repair (< 1 year of age) have postoperative results similar to those of children who undergo repair at an older age. Complications related to shunts are prevented by the infant repairs, and, in the future, reduced ventricular ectopy may be demonstrated to be a benefit of such repairs.  相似文献   

10.
In a previous paper we demonstrated that human polymorphonuclear cells (PMN) in the presence of normal human serum (NHS) secrete proinflammatory cytokines in response to Cryptococcus neoformans or its major capsular component, glucuronoxylomannan (GXM). The hypothesis that activation of the complement system could be responsible for the observed phenomenon is supported by the fact that encapsulated and acapsular C. neoformans isolates are activators of the complement system and, in particular, large encapsulated isolates are powerful activators. In the present study we demonstrate that (i) interleukin-8 (IL-8) release in response to acapsular or encapsulated strains of C. neoformans is significantly reduced in the presence of heat-inactivated serum rather than NHS and is completely abrogated in the absence of human serum; (ii) GXM-induced IL-8 release is strictly dependent on the presence of NHS, is inhibited by specific antibodies to either C3a and C5 complement components, and is completely abrogated by the combined use of these antibodies; (iii) the addition of purified C3a and C5a directly stimulates IL-8 release by PMN; and (iv) monoclonal antibody to GXM in combination with GXM or encapsulated C. neoformans potentiates IL-8 release by PMN. These data shed light on the mechanism involved in GXM-induced IL-8 secretion by PMN, provide an additional potential role for complement in the control of C. neoformans infections, and suggest a complex interplay between the complement system, humoral immunity, and cytokine regulation.  相似文献   

11.
The serotonin (5-HT)(2A/2c) agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), the 5-HT2C agonist 6-chloro-2-[1-piperazinyl]-pyrazine and the 5-HT2A partial agonist m-chloro-phenylpiperazine (mCPP) were injected bilaterally into the medial prefrontal cortex of male rats. DOI and mCPP, but not 6-chloro-2-[1-piperazinly]-pyrazine, elicited a dose-dependent head-twitch response (HTR). DOI-induced HTR had an ED50 of 12.8 nmoles/0.5 microl/side and was inhibited by the 5-HT2A antagonists ketanserin and MDL 100,907 but was not blocked by pretreatment with the selective 5-HT(2C/2B) antagonist SDZ SER 082. The HTR to mCPP demonstrated a bell-shaped dose-response curve with an ED50 of 1.5 nmoles/0.5 microl/side and a peak effect after 3 nmoles/side. The response to mCPP was greatly diminished by both ketanserin and MDL 100,907 and was partially reversed by SDZ SER 082. These findings suggest that the HTR produced by the direct injection of serotonergic agonists into the medial prefrontal cortex is, in part, mediated by the activation of 5-HT2A receptors. Pretreatment of rats with the 5-HT1A agonist (+/-)-8-hydroxy-dipropylaminotetralin hydrobromide inhibited the HTR to DOI. This is consistent with other evidence that suggests a functional antagonism between 5-HT1A and 5-HT2A receptor activation. The HTR to DOI was potentiated by the novel 5-HT1A selective antagonist WAY 100,635, which suggests that 5-HT1A receptors tonically regulate this behavioral response to stimulation of cortical 5-HT2A receptors.  相似文献   

12.
BACKGROUND & AIMS: Mutations in hepatitis C virus (HCV) nonstructural protein 5A (NS5A) may correlate with response to interferon in Japanese patients with chronic hepatitis C. The aim of this study was to examine whether these findings could be expanded to European patients infected with genotypes associated to low (1b) or high (3a) response rates. METHODS: Pretreatment serum samples of 66 patients with chronic HCV infection, 48 infected with genotype 1b and 18 with 3a, were analyzed. RESULTS: Among patients infected with genotype 3a, 1 of 7 long-term responders and none of 11 nonresponders showed NS5A amino acid mutations. Among patients infected with genotype 1b, all 7 long-term responders, but also 27 of 41 nonresponders, showed NS5A mutations. There was no correlation between number of mutations and response to therapy. In 10 patients, sequences obtained before and after treatment were compared and failed to show any change. Serum HCV RNA levels did not differ between patients with and without mutations in NS5A sequence. CONCLUSIONS: No significant correlation was found in patients infected with genotypes 1b or 3a between NS5A sequence and response to interferon alfa. NS5A mutations do not correlate with viral load. Changes in this region were not found during interferon alfa treatment.  相似文献   

13.
5-Thiomannose-containing oligomannoside mimics, 5SMan alpha(1,6)Man, 5SMan alpha(1,3)Man, 5SMan alpha(1,6)?Man alpha(1,3)Man?, Man alpha(1,6)?5SMan alpha(1,3)Man?, and 5SMan alpha(1,6)?5SMan alpha(1,3)Man?, were synthesized. Dissociation constants for the binding of these mimics to concanavalin A (ConA) were determined by a fluorescence anisotropy inhibition assay. Comparison of these data with those of the natural oligomannosides and with a crystal structure of the trimannoside-ConA complex established that replacing a ring oxygen atom with a sulfur atom causes about 1 kcal/mol decrease in the binding free energy when the ring oxygen is recognized with a hydrogen bonding.  相似文献   

14.
15.
Enzootic nasal tumour (ENT) and sheep pulmonary adenomatosis (SPA) are two contagious adenocarcinomas of the respiratory tract of sheep and goats. Both diseases are associated with related, but distinct, type-D-retroviruses (ENTV and JSRV respectively). No evidence of circulating antibodies has been described in animals affected by either ENT or SPA using antigens from natural sources. We evaluated the usefulness of a recombinant JSRV capsid protein (JSRV-CA) as antigen to study the antibody responses of animals naturally affected by ENT or SPA, using immunoblotting. Positive reactions were detected in the sera of both affected and unaffected sheep and goats. The reactivity was abolished completely by absorption with the GST fusion partner but not by JSRV-CA, suggesting that it was not specific. The results support prior observations indicating that sheep and goats infected by JSRV and ENTV do not develop specific humoral responses to these retroviruses.  相似文献   

16.
A possible role of metabolism by cytochrome P450 (P450) in ethyl carbamate-induced suppression of the antibody response to a T-cell-dependent antigen, sheep erythrocytes (SRBCs), was investigated in female Balb/C mice. When mice were treated with ethyl carbamate intraperitoneally for 14 consecutive days at 25, 50, 100, 200 and 400 mg/kg, the antibody response was significantly suppressed from 200 mg/kg. These doses also caused a decrease in thymus weight. An acute dosing of ethyl carbamate at 1 g/kg also caused not only a significant suppression of the antibody response, but also a decrease in thymus weight. The antibody response was most likely to be the IgM antibody response, which was demonstrated in a haemagglutination study. When mice were pretreated with phenobarbital (80 mg/kg) for 3 days to induce P450 enzymes, followed by administration of ethyl carbamate intraperitoneally for 7 consecutive days, the antibody response was more suppressed than in saline-pretreated controls. Moreover, a study using aminoacetonitrile, a P450 inhibitor, showed that the antibody response suppressed by ethyl carbamate was completely recovered by the inhibitor. The present results suggest that metabolism of ethyl carbamate by P450 may be the critical pathway to produce metabolites capable of suppressing the antibody response.  相似文献   

17.
18.
Peptide 161-180 of human interphotoreceptor retinoid-binding protein (IRBP) contains a major uveitogenic epitope for mice of the H-2r haplotype. The human and bovine homologs differ from the autologous murine homolog by three and four amino acid residues, respectively. We compare the immunogenicity and pathogenicity of the three homologs, and investigate their ability to induce oral tolerance to experimental autoimmune uveoretinitis (EAU) induced by the autologous peptide. All three 161-180 homologs were pathogenic, with a hierarchy: human > murine > bovine. All crossreacted with each other and with IRBP. Feeding any of the three homologs (6 x 200 microg over 2 weeks) lowered antigen-specific responses and protected from EAU induced by the autologous homolog, and reduced EAU induced with whole IRBP. Peptide-fed mice had a reduced frequency of peptide-reactive T cells, suggesting a mechanism involving anergy and/or deletion. The results indicate that non-identical, but crossreactive, heterologous epitopes can protect against EAU induced by the corresponding autologous epitope, and even by the whole multi-epitope protein. These findings may impact on clinical trials in which uveitis patients are undergoing oral immunotherapy with bovine retinal antigens.  相似文献   

19.
Using sera from hepatitis C virus (HCV)-infected patients and noninfected subjects to screen random peptide libraries displayed on phage, we selected peptides specifically reacting with sera from infected patients. These phage- borne peptides were shown to mimic distinct HCV determinants. They detected in all cases the presence of anti-HCV Abs in a large panel of patients' sera, thus demonstrating the high sensitivity of the selected peptides as diagnostic markers. In addition, this diagnostic approach allowed a detailed characterization of the individual humoral response to viral infection. Phage-displayed HCV mimics were substitutes for the authentic HCV epitopes in inducing a strong specific response against HCV when used as immunogens in mice. These results support the search for HCV mimics with the potential to elicit a protective immune response as leads for the development of a mimotope-based vaccine against viral infection.  相似文献   

20.
Interaction between protein disulfide isomerase, possessing not only isomerase but also chaperone-like activity, and olygomeric enzyme, GAPDH, has been studied using technique of immobilization on insoluble support. PDI dimers bound to CNBr-activated Sepharose were shown to possess high TPOR activity as well as the ability to reactivate lysozyme. Immobilized PDI was not found to interact neither with soluble tetrameric GAPDH, nor with soluble denatured GAPDH. However, soluble PDI binds effectively to immobilized GAPDH monomers; Kd was found to be 3.7 x 10(-6) M, stoichiometry 0.824 mole PDI monomers per mole GAPDH monomers. Immobilized GAPDH tetramers do not interact with PDI. These observations are also confirmed by the data on electrophoresis of proteins bound to immobilized GAPDH monomers and tetramers. The ability of PDI to interact with denatured protein form, but not with the native one, is considered to be evidence of chaperone-like activity of the enzyme.  相似文献   

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