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41.
Immunization with dendritic cells (DCs) using various Ag-loading approaches has shown promising results in tumor-specific immunotherapy and immunoprevention. Fused cells (FCs) that are generated from DCs and tumor cells are one of effective cancer vaccines because both known and unknown tumor Ags are presented on the FCs and recognized by T cells. In this study, we attempted to augment antitumor immunity by the combination of DC-tumor FC vaccination with immunostimulatory oligodeoxynucleotides containing CpG motif (CpG ODN). Murine DCs were fused with syngeneic tumor cells ex vivo using inactivated hemagglutinating virus of Japan (Sendai virus). Mice were intradermally (i.d.) immunized with FCs and/or CpG ODN. Coadministration of CpG ODN enhanced the phenotypical maturation of FCs and unfused DCs, and the production of Th1 cytokines, such as IFN-gamma and IL-12, leading to the induction of tumor-specific CTLs without falling into T cell anergy. In addition, immunization with FCs + CpG ODN provided significant protection against lethal s.c. tumor challenge and spontaneous lung metastasis compared with that with either FCs or CpG ODN alone. Furthermore, among mice that rejected tumor challenge, the mice immunized with FCs + CpG ODN, but not the mice immunized with FCs or CpG ODN alone, completely rejected tumor rechallenge, indicating that CpG ODN provided long-term maintenance of tumor-specific immunity induced by FCs. Thus, the combination of DC-tumor FCs and CpG ODN is an effective and feasible cancer vaccine to prevent the generation and recurrence of cancers.  相似文献   
42.
Existence of a Mr = 56,000 polypeptide associated with 10S DNA polymerase alpha was shown by production of a monoclonal anti-calf thymus 10S DNA polymerase alpha antibody secreted from a hybridoma line named 3H1. The antibody bound three polypeptides with Mr = 180,000, 56,000 and 32,000 in hydroxylapatite fraction of 10S DNA polymerase alpha by immunoblot. The antibody co-precipitated the polypeptides with the large polypeptide (Mr = 150,000-140,000) of 10S DNA polymerase alpha with the aid of second antibody. Among three polypeptides, the Mr = 56,000 polypeptide was co-purified with DNA polymerase alpha through DNA-cellulose chromatography and repeated sucrose rate-zonal centrifugations. The Mr = 56,000 polypeptide was still associated with 10S DNA polymerase alpha after second sucrose rate-zonal centrifugation, but the amount of it was reduced. The polypeptide was banded at pH 7.2-8.0 and displayed microheterogeneity in respect of isoelectric point by isoelectrofocusing with 7 M urea, and showed weak DNA-binding property after blotting onto a nitrocellulose. The antibody against the polypeptide precipitated DNA polymerase alpha from human, rat, and mouse, and Mr = 56,000 and 32,000 polypeptides were detected in these DNA polymerase alpha fractions by immunoblot. These results suggest that the polypeptide with Mr = 56,000 may take part in the DNA polymerase reaction.  相似文献   
43.
We isolated two new keratin cDNAs by screening a cDNA library constructed from poly(A)+ RNA of the dorsal and abdominal skin of C57BL/10J mice with a probe of human KRT14. Due to its high sequence homology to human keratin 17 cDNA, one full-length cDNA is most likely to be mouse keratin 17 (Krt1-17) cDNA. The other is the putative full-length cDNA of a novel type I keratin gene, designated Krt1-c29. These two keratin genes were mapped to the distal portion of Chromosome 11, where the mouse keratin gene complex-1 (Krt1) is localized. To elucidate the genomic organization of Krt1 in mice, we carried out genetic and physical analyses of Krt1. A large-scale linkage analysis using intersubspecific backcrosses suggested that there are two major clusters in Krt1, one containing Krt1-c29, Krt1-10, and Krt1-12 and the other containing Krt1-14, -15, -17, and -19. Truncation experiments with two yeast artificial chromosome clones containing the two clusters above have revealed that the gene order of Krt1 is centromere-Krt1-c29-Krt1-10-Krt1-12-Krt1-13-K rt1-15-Krt1-19-Krt1-14-K rt1-17-telomere. Finally, we analyzed sequence divergence between the genes belonging to the Krt1 complex. The results clearly indicated that genes are classified into two major groups with respect to phylogenetic relationship. Each group consists of the respective gene cluster demonstrated by genetic and physical analyses in this study, suggesting that the physical organization of the Krt1 complex reflects the evolutionary process of gene duplication of this complex.  相似文献   
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45.
The novel chemical structure and immunobiological activities of Prevotella intermedia ATCC 25611 lipid A were investigated. A lipopolysaccharide (LPS) preparation of P. intermedia was extracted using a phenol-chloroform-petroleum ether method, after which its purified lipid A was prepared by weak acid hydrolysis followed by chromatographic separations. The lipid A structure was determined by mass spectrometry and nuclear magnetic resonance to be a diglucosamine backbone with a phosphate at the 4-position of the non-reducing side sugar, as well as five fatty acids containing branched long chains. It was similar to that of Bacteroides fragilis and Porphyromonas gingivalis, except for the phosphorylation site. P. intermedia lipid A induced weaker cytokine production and NF-kappaB activation in murine cells via Toll-like receptor (TLR) 4 as compared to Escherichia coli synthetic lipid A (compound 506). Our results indicate that P. intermedia lipid A activates cells through a TLR4-dependent pathway similar to E. coli-type lipid A, even though these have structural differences.  相似文献   
46.
In the course of gene array studies aimed at identifying IFN-stimulated genes associated with interferon beta (IFN-beta)-induced apoptosis, we identified X-linked inhibitor of apoptosis-associated factor-1 (XAF1) as a novel IFN-stimulated gene. XAF1 mRNA was up-regulated by IFN-alpha and IFN-beta in all cells examined. However, IFNs induced high levels of XAF1 protein predominantly in cell lines sensitive to the proapoptotic effects of IFN-beta. In apoptosis-resistant cells including WM164 melanoma, WM35 melanoma, U937 pro-monocytic leukemia, and HT1080 fibrosarcoma cells, XAF1 mRNA was strongly up-regulated but XAF1 protein was up-regulated only weakly or not at all. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a critical mediator of IFN-beta-induced apoptosis, but most melanoma cell lines were resistant to recombinant TRAIL protein. For example, A375 melanoma cells were defective in TRAIL induction by IFN-beta and were resistant to TRAIL-induced apoptosis. However, IFN-beta pretreatment sensitized them to subsequent recombinant TRAIL-induced apoptosis. A375 cells expressing XAF1 constitutively were more sensitive to TRAIL-induced apoptosis compared with empty vector-transfected cells. The degree of sensitization by XAF1 was similar to that provided by IFN pretreatment and was correlated with the level of XAF1 expressed. Furthermore, the overexpression of the zinc-finger portion of XAF1 blocked IFN-dependent sensitization of A375 melanoma cells to the proapoptotic effects of TRAIL. These results suggested that IFN-dependent induction of XAF1 strongly influenced cellular sensitivity to the proapoptotic actions of TRAIL.  相似文献   
47.
48.
Adult-onset type II citrullinemia (CTLN2) is characterized by a liver-specific argininosuccinate synthetase deficiency caused by a deficiency of the citrin protein encoded by the SLC25A13 gene. Until now, however, no SLC25A13 mutations have been reported in children with liver diseases. We described three infants who presented as neonates with intrahepatic cholestasis associated with hypermethioninemia or hypergalactosemia detected by neonatal mass screening. DNA analyses of SLC25A13 revealed that one patient was a compound heterozygote for the 851de14 and IVS11+IG-->A mutations and two patients (siblings) were homozygotes for the IVS11+lG-->A mutation. These results suggested that there may be a variety of liver diseases related to CTLN2 in children.  相似文献   
49.
To investigate the possible involvement of histamine H(3) receptors in renal noradrenergic neurotransmission, effects of (R)alpha-methylhistamine (R-HA), a selective H3-receptor agonist, and thioperamide (Thiop), a selective H3-receptor antagonist, on renal nerve stimulation (RNS)-induced changes in renal function and norepinephrine (NE) overflow in anesthetized dogs were examined. RNS (0.5-2.0 Hz) produced significant decreases in urine flow and urinary sodium excretion and increases in NE overflow rate (NEOR), without affecting renal hemodynamics. When R-HA (1 microg x kg(-1) x min(-1)) was infused intravenously, mean arterial pressure and heart rate were significantly decreased, and there was a tendency to reduce basal values of urine flow and urinary sodium excretion. During R-HA infusion, RNS-induced antidiuretic action and increases in NEOR were markedly attenuated. Thiop infusion (5 microg x kg(-1) x min(-1)) did not affect basal hemodynamic and excretory parameters. Thiop infusion caused RNS-induced antidiuretic action and increases in NEOR similar to the basal condition. When R-HA was administered concomitantly with Thiop infusion, R-HA failed to attenuate the RNS-induced antidiuretic action and increases in NEOR. However, in the presence of pyrilamine (a selective H1-receptor antagonist) or cimetidine (a selective H2-receptor antagonist) infusion, R-HA attenuated the RNS-induced actions, similarly to the case without these antagonists. Thus functional histamine H3 receptors, possibly located on renal noradrenergic nerve endings, may play the role of inhibitory modulators of renal noradrenergic neurotransmission.  相似文献   
50.
Achiral carbocyclic "DL-like" 5'-nor nucleosides have been synthesized and analyzed by the chiral capillary electrophoresis to elucidate the "D-like" monomers.  相似文献   
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