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1.
    
Partial and total loss of function mutant alleles of a putative Drosophila homologue (DPhK-) of the vertebrate phosphorylase kinase -subunit gene have been isolated. DPhK- is required in early embryonic processes, such as gastrulation and mesoderm formation; however, defects in these processes are seen only when both the maternal and zygotic components of DPhK- expression are eliminated. Loss of zygotic expression alone does not appear to affect normal embryonic and larval development; some pupal lethality is observed but the majority of mutant animals eclose as adults. Many of these adults show defects in their leg musculature (e.g. missing and degenerating muscles), in addition to exhibiting melanised tumours on their leg joints. Loss of only the maternal component has no obvious phenotypic consequences. The DPhK gene has been cloned and sequenced. It has an open reading frame (ORF) of 1680 by encoding a 560 amino acid protein. The predicted amino acid sequence of DPhK- has two conserved domains, the catalytic kinase and calmodulin-binding domains, separated by a linker sequence. The amino acid sequence of DPhK- is homologous to that of mammalian PhK- proteins but differs in the length and amino acid composition of its linker sequence. The expression of DPhK- mRNA is developmentally regulated. We discuss the implications of these observations.  相似文献   

2.
Interferon- (IFN-) and tumor growth inhibitory factor (TGIF) were inducedin vitro in the supernatant from mixed culture of human peripheral blood mononuclear cells (PBMC) and OK-432. TGIF activity was determined by growth inhibition of a human gastric adenocarcinoma cell line, MK-1 cells, and IFN- activity was measured by radioimmunoassay. The production of TGIF and IFN- was time-dependent, reaching its maximum around 48 hrs. Although there was no significant correlation between TGIF production and IFN- production, combination of a subthreshold concentration of recombinant IFN- (rIFN-) and TGIF induced significant growth inhibition of MK-1 cells. This fact indicates that the effects of rIFN- and TGIF are synergistic. The antiproliferative effect of these cytokines are highly species-specific, and their synergistic effects were also species-specific. rIFN--sensitive and -resistant clones were successfully established from the original MK-1 cell line; those clones are both sensitive to TGIF. Synergistic antiproliferative effects were found when the rIFN--sensitive clone, but not the resistant clone, was used as a target, suggesting that the synergistic effects require the target cells' sensitivity to IFN-. These results indicate that the synergistic effects of TGIF and IFN- may produce a clinical antitumor action in cancer patients receiving OK-432 administration.  相似文献   

3.
Proteolytic cleavage of recombinant human interferon- (IFN-) expressed in Chinese hamster ovary (CHO) cells during batch fermentation has been monitored by mass spectrometric peptide mapping. IFN- was purified from cell-free culture supernatant by immunoaffinity chromatography and cleaved by endoprotease Asp-N. Peptide fragments were resolved by reverse-phase HPLC and identified by a combination of matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) and automated N-terminal peptide sequencing. Using this approach, a peptide was identified as the C-terminal fragment of the IFN- polypeptide. Analysis of this peptide by MS indicated that the recombinant IFN- polypeptide secreted by CHO cells was truncated by at least ten amino acids, initially at Gln133-Met134. No full length (143 amino acids) polypeptide molecules were observed at any stages of the fermentation. Additional proteolytic cleavages at basic amino acids N-terminal of Gln133 occurred during the later stages of the culture resulting in a heterogeneous IFN- polypeptide population with 'ragged' C-termini.  相似文献   

4.
    
-Crystallin is the major and most abundant lens protein present in the eye lens of lower vertebrates such as amphibian and piscine species. To facilitate structural characterization of-crystallins isolated from the lens of the bullfrog (Rana catesbeiana), a cDNA mixture was synthesized from the poly(A)+mRNA isolated from fresh eye lenses. cDNA encoding-crystallin was then amplified using polymerase chain reaction (PCR) based on two primers designed according to the relatively conserved N- and C-terminal sequences of known-crystallins from teleostean fishes. PCR-amplified product corresponding to-crystallin isoforms was obtained, which was then subcloned in pUC18 vector and transformed intoEscherichia coli strain JM109. Plasmids containing amplified-crystallin cDNAs were purified and prepared for nucleotide sequencing by the dideoxynucleotide chain-termination method. Sequencing several clones containing DNA inserts of about 0.54 kb revealed the presence of two isoforms with an open reading frame of 534 base pairs, covering two-crystallins each with a deduced protein sequence of 177 amino acids including the translation-initiating methionine. These-crystallins of pI 6.364 and 6.366 contain a low-methionine content of 2.81%, in contrast to 11–16% obtained for those-crystallins with high-methionine content from most teleostean lenses. Pairwise sequence comparison of bullfrog-crystallins with those published sequences of-crystallins from carp, shark,Xenopus and anotherRana frog, bovine, and human lenses indicates that there is only 46–63% sequence similarity among these species, revealing that amphibians possess a very complex and heterogeneous group of-crystallins even from closely related species ofRana frogs. The sequence analysis and comparison of various isoforms of the frog-crystallin family provide a firm basis for identifying these lens proteins as members of a multigene family more complex than that reported for mammalian-crystallins.  相似文献   

5.
A systematic characterization of lens crystallins from five major classes of vertebrates was carried out by exclusion gel filtration, cation-exchange chromatography and N-terminal sequence determination. All crystallin fractions except that of -crystallin were found to be N-terminally blocked. -Crystallin is present in major classes of vertebrates except the bird, showing none, or decreased amounts, of this protein in chicken and duck lenses, respectively. N-Terminal sequence analysis of the purified -crystallin polypeptides showed extensive homology between different classes of vertebrates, supporting the close relatedness of this family of crystallin even from the evolutionarily distant species. Comparison of nucleotide sequences and their predicted amino acid sequences between -crystallins of carp and rat lenses and heat-shock proteins demonstrated partial sequence homology of the encoded polypeptides and striking homology at the gene level. The unexpected strong homology of complementary DNA (cDNA) lies in the regions coding for 40 N-terminal residues of carp -II, rat 2-1, and the middle segments of 23,000- and 70,000-M r heat-shock proteins. The optimal alignment of DNA sequences along these two segments shows about 50% homology. The percentage of protein sequence identity for the corresponding aligned segments is only 20%. The weak sequence homology at the protein level is also found between the invertebrate squid crystallin and rat -crystallin polypeptides. These results pointed to the possibility of unifying three major classes of vertebrate crystallins into one // superfamily and corroborated the previous supposition that the existing crystallins in the animal kingdom are probably mutually interrelated, sharing a common ancestry.  相似文献   

6.
Adoptive immunotherapy using MHC-nonrestricted-lymphocytes, peripheral blood T cells and NK cells was devised. Peripheral blood mononuclear cells (3 x 107) were selected by immobilization to anti-CD3 monoclonal antibody for 4 days and cultured for 2 weeks in the presence of IL-2. Thereafter they were reactivated by 500 U/ml of IFN- and 1000 U/ml of IL-2 for 1 hour. Enhancement of NK and LAK activities was confirmed. Peripheral blood T cells proliferated in response to immobilized anti-CD3 antibody (3% to 30%). Approximately 6 x 109 BRM-activated killer (BAK) cells composed of CD56+ T cells and CD56+ NK cells, were dispensed to cancer patients via intravenous drip infusion. Nine patients were treated with BAK cells every 2 weeks or every month on an outpatient basis. During the course of adoptive immunotherapy, the crossed affinity immunoelectrophoresis (CAIE) pattern of serum immunosuppressive acidic protein (IAP) was analysed. Both the production and glycosylation pattern of IAP is changed in response to tumor enlargement and may therefore act as a marker of the disease progression. During the course of BAK therapy, the glycosylation IAP pattern of 6 patients changed from tumor (T) to normal (N). In addition, the performance status of all patients was maintained at 90–100% of the Karnofsky scale and any side effects including fever were not observed during treatments with BAK cells. Moreover, the overall quality of life (QOL) of the patients, scored at the Face scale was favorable. In addition, blood levels of activated T cells producing IFN- were assayed as an indication marker of BAK therapy. The normal range of IFN- producing T cells comprised 6.9 ± 0.9% of peripheral blood mononuclear cells (PBMC), according to a single cell FACScan analyses of PBMCs derived from normal individuals. IFN- producing T cells of Patients No. 8 and 9, who received extensive chemotherapy before initiation of BAK therapy, comprised only 0.2% and 2% of PBMC, respectively. These patients died 3 and 6 months after beginning BAK therapy. Peripheral blood T cells of Patients Nos. 1–7 proliferated in response to immobilized anti-CD3 antibody and the frequency of IFN- producing T cells in PBMC preparation of these patients were over 3% before initiation of BAK therapy. Since our data show a positive correlation between survival time and initial T cell counts, a low frequency of these cells may contraindicate BAK therapy.  相似文献   

7.
N(3, 4-dimethoxycinnamoyl) anthranilic acid (Tranilast) inhibits antibody-mediated hypersensitivity reactions, and is an effective drug for patients with bronchial asthma or allergic rhinitis. Interferon- (IFN-) production of ovalbumin (OA)-stimulated peripheral blood mononuclear cells (PBMCs) from hen's egg-sensitive patients with atopic dermatitis (AD) was significantly higher than those of healthy controls. Tranilast inhibited this IFN- production. Moreover, interleukin-2 (IL-2) production of OA-stimulated PBMCs from hen's egg-sensitive patients with AD was also inhibited by Tranilast. Our results suggest that Tranilast can be used to the patients with food sensitive AD.Abbreviations PBMCs peripheral blood mononuclear cells - OA ovalbumin - BSA bovine serum albumin - AD atopic dermatitis - IL-2 interleukin-2 - IFN- interferon- - Tranilast N(3, 4-dimethoxycinnamoyl) anthranilic acid - IL-4 interleukin 4 - IL-5 interleukin 5  相似文献   

8.
Summary Our previous observations indicated that mutants partially resistant to IFN-y cytotoxicity were defective in the induction of indoleamine 2,3-dioxygenase, (IDO). Two mutants highly resistant to IFN- were isolated following a second round of mutagenesis. The resistance to IFN- was inversely correlated with the inducibility of IDO in these mutants. Moreover, several other IFN- responsive genes, including those encoding 2-5A synthetase, GTP cyclohydrolase and HLA-DR, were also differentially altered in their expression upon INF- treatment. IFN-y receptor gene expression was not changed nor was the binding of the receptor to IFN-. Southern blot analysis failed to reveal any significant abnormality in the IDO gene structure in these mutants. We therefore suggest that these mutants are defective in the IFN- signaling pathway and will be useful in further analysis of the biochemical mechanism of IFN- activated gene expression in target cells.  相似文献   

9.
The impact of type 1 diabetes mellitus on liver -glutamyltranspeptidase, a premalignant marker, was studied. Diabetes was induced in male Sprague Dawley and Fischer 344 rats by administration of Streptozotocin, which produced a stable and moderately severe diabetic state. In liver homogenates, -glutamyltranspeptidase was increased over control levels: 1.2, 8.1 and 13,2 fold in Strague-Dawley rats; 4.8, 58.4 and 84.7 fold in Fischer 344 rats; at 1, 3 and 6 weeks following Streptozotocin treatment. In plasma membranes isolated from the livers of Fischer 344 rats, -glutamyltranspeptidase was increased over control levels: 5.6, 75 and 127 fold at weeks 1, 3 and 6 following Streptozotocin treatment. The relative specific activity of 5-nuleohdase was found to be similar: 9–14, indicating comparable degrees of plasma membrane purity. Plasma glutamate-pyruvate transaminase levels were minimally and similarly affected at all time points indicating lack of association of increasing -glutamyltranspeptidase activity with overt liver damage. Thyroid hormone replacement, with both T3 (0.6 g/Kg) once a day and T4 (6.0 g/kg) twice a day for three days elicited a further 30% increment in enzyme activity. Insulin replacement (20–40 units/200 g body weight) twice a day for five days reduced enzyme activity 51% at week 6. This was associated with an increase in -glutamyltranspeptidase in the plasma from 14 fold over control levels in the diabetic state at week 6 to 53 fold ever control levels after insulin replacement at week 6. It is proposed that the diabetes-induced increase in -glutamyltranspeptidase is reduced by an insulin-directed shedding of the enzyme into the plasma.  相似文献   

10.
Three -glutamyltranspeptidase (enzymes I, II and III) were partially purified from the cell free extracts of the cultured mycelia of Morchella esculenta Fr. The molecular masses of enzymes were 155,000 (I), 219,000 (II) and 102,000 (III). All of them catalyzed both hydrolysis and transpeptidation of various -glutamyl compounds. -l-Glutamyl-cis-3-amino-l-proline occurring in the cultured mycelia of this fungus was a good substrate for both reactions. K m values for hydrolysis were in the order of 10-4 to 10-5 M, and those for transpeptidation were in the order of 10-2 to 10-4 M. The enzymes were inhibited by a -glutamyltranspeptidase inhibitor, l-serine plus borate.Abbreviations -GTP -glutamyltranspeptidase - HPLC High-performance liquid chromatography  相似文献   

11.
The efficacy of systemic infusion of recombinant human macrophage-colony-stimulating factor (M-CSF) in combination with local treatment with human recombinant tumor necrosis factor (TNF) and mouse recombinant interferon (IFN) was studied in vivo on a subclone of B16 melanoma (MmB16) in mice. Short-term intravenous administration of M-CSF at a dose of 106 units daily had no antitumor effect in vivo. Similarly, local treatment of tumor with TNF (5 g daily) did not produce any therapeutic effect. However, simultaneous administration of the same dose of TNF with IFN (1000 units daily) resulted in a synergistic effects manifested by the retardation of tumor growth. Addition of systemic infusion of M-CSF to the local therapy with TNF and IFN induced further augmentation of antitumor efficacy and delayed progression of MmB16 melanoma. The strengthened antitumor effect of combination therapy including M-CSF, TNF and IFN was most probably due to the increased release of monocytes from the bone marrow, their recruitment into the site of tumor growth and subsequent local stimulation of their antitumor activity.  相似文献   

12.
Summary Five monoclonal antibodies raised against an enriched C hordein fraction have been characterized in detail and were found to be specific for the members of the sulphur-rich hordein family. Two antibodies specific for B hordein polypeptides were identified, one of which reacted predominantly with CNBr cleavage class III polypeptides. 1 hordein was recognized by two antibodies, of which one also reacted with 2 hordein and several members of the CNBr cleavage class II B hordein polypeptides. One antibody recognized 3 hordein but cross-reacted at higher antibody concentration with almost all of the B and C hordein polypeptides. The specificity of the monoclonal antibodies was confirmed by Western blotting of one- or two-dimensionally separated hordein from the B hordein-deficient mutant hor2ca and its wild-type Carlsberg II and the 3 hordein-deficient genotype Nevsky. The identification of the hordein-specific monoclonal antibodies was further supported by immune precipitation of in-vitro transcribed and translated 2 hordein, and hor2ca and Carlsberg II mRNA translation products. The monoclonal antibodies were used to screen for mutants in hordein synthesis. Two mutants, one deficient in 1 hordein synthesis and a second in 2 or closely related B hordein polypeptides were identified. A model is proposed for the evolution of the sulphur-rich hordein loci Hor5 and Hor2.  相似文献   

13.
Although the proinflammatory cytokine interferon- (IFN-) has been generally thought to enhance antitumor immune responses and be involved in antitumor mechanisms of many other immunotherapy molecules, it has also been reported that IFN- could promote tumor immune evasion. In this report, by using an ideal mouse model that expresses IFN- locally in muscle, we demonstrate that sustained low-level expression of IFN- promotes the development of several types of tumor including H22 hepatoma, MA782/5S mammary adenocarcinoma and B16 melanoma. However, transitory expression of IFN- does not have such an effect. On the other hand, sustained high-level expression of IFN- mediates significant antitumor effect on H22 hepatoma. Low level of IFN- upregulates expression of PD-L1, PD-L2, CTLA-4 and Foxp3, which may partly account for the tumor immune evasion promoted by IFN-. Furthermore, blockade of PD-L inhibits IFN-s tumor-promoting effect. Our findings provide a mechanistic link between chronic inflammation and cancer and would have potential implications for cancer prevention and also for the design of cytokine–based cancer immunotherapy.  相似文献   

14.
The integration of Fas/Apo-1 (CD95) by Fas ligand or anti-Fas antibody induces apoptosis, and this system plays a pivotal role for the lysis of target cells by cytotoxic T lymphocytes. Fas-mediated apoptosis is also increased by a prior incubation of Fas-bearing cells with interferon(IFN)-. Interleukin-1- converting enzyme (ICE) and/or CPP32, or other members of ICE family act as direct cell death executors downstream of this mechanism, and a tetrapeptide inhibitor of these cysteine proteases blocks Fas-mediated apoptosis. In this study, we examined the effect of IFN- on Fas-mediated apoptosis in ACHN cells. IFN- augmented apoptosis in a dose dependent manner and reached a plateau at 400 U/ml when exposed for 48 h before the end of culture. The kinetics revealed a significant increase in apoptosis after 24 h. Exposing ACHN cells to IFN- increased pro-ICE expression accompanied with a decrease of pro-CPP32. These results suggest that direct enhancement of ICE expression and/or upregulation of conversion of pro-CPP32 to active form increases Fas-mediated apoptosis by IFN- in ACHN cells.  相似文献   

15.
This work examines the efficacy of radiation in reducing the viability of certain contaminating bacteria of sugar-cane must and the consequential beneficial effect of lethal doses of radiation on some physiological parameters of the yeast-based ethanolic fermentation. The must from sugar-cane juice was inoculated with different bacteria that usually contaminate the must in the production facilities: Bacillus and Lactobacillus. The contaminated must was irradiated at 2.0, 4.0, 6.0, 8.0 and 10.0 kGy of gamma radiation. The population density of the bacteria in the irradiated must was recorded. Ethanolic fermentation by yeast (Saccharomyces cerevisiae) was carried out and the total acidity, the volatile acidity and the organic acids (lactic and acetic) produced during the fermentation were determined. The ethanol yield was also recorded. The treatment with radiation reduced the population of the contaminating microorganisms of the sugar-cane must. The acidity and the organic acids (lactic and acetic) produced during the fermentation decreased as the dose of radiation applied to the must increased. It is concluded that irradiation was efficient in decontaminating the sugar-cane must and improved the biochemical parameters of the ethanolic fermentation, including the ethanol yield by 2%.  相似文献   

16.
We investigated the influence of the combined use of sizofiran, a-1,3-glucan and a recombinant interferon- (rIFN-) upon biological activities of peritoneal macrophages (M). The number of peritoneal M and the production of cytokines (interleukin-1, interferon- and tumor necrosis factor) was increased by the combined treatment. Fully activated peritoneal M based on the increased number of elongated pseudopods were observed by electromicroscope. Sizofiran seems to assure a sufficient supply of M to kill tumor cells in the peritoneal cavity and co-administered rIFN- seems to directly stimulate the accumulated M in addition to its direct cytotoxicity against tumor cells. This combination therapy may be a step to the prevention of the recurrence of gynecological malignancies including ovarian cancer, after a negative second-look laparotomy.Abbreviations rIFN- recombinant interferon- - IL-1 interleukin-1 - TNF tumor necrosis factor - SLL second look laparotomy  相似文献   

17.
Gene modification of tumor cells with the cDNA for interferon (IFN) has been shown to increase the immunogenicity of some tumor cells. In order to explore further the possible therapeutic relevance of these previous findings, two clones of the nonimmunogenic MCA-102 fibrosarcoma of C57BL/6 origin were retrovirally transduced with the cDNA encoding murine IFN: 102.4JK (4JK), a clone with relatively high major histocompatibility complex (MHC) class I expression, and 102.24JK (24JK), a clone with low expression of surface MHC class I molecules. Retroviral transduction of tumor cells with the cDNA encoding for IFN resulted in a substantial up-regulation of MHC class I surface expression in the 24JK clone but little change of class I in the 4JK clone. In an attempt to generate antitumor lymphocytes, these gene-modified cells were inoculated into mouse footpads and draining lymph nodes (DLN) were removed, dispersed, and cultured in vitro for 10 days with irradiated tumor cells and interleukin-2. DLN from mice bearing either unmodified tumor or tumor transduced with cDNA encoding neomycin resistance (Neo R) or IFN, were used to treat recipients harboring 3-day pulmonary metastases induced by the parental, unmodified tumor. Treatment with DLN cells obtained following the injection of 24JK tumor cells modified with the gene for IFN significantly reduced the number of pulmonary metastases in four separate experiments, compared to groups treated by DLN cells generated from inoculation of either the unmodified, parental 24JK clone or the same clone transduced with theNeo R gene only. In contrast, DLN cells induced either by IFN-transduced 4JK (high expression of MHC class I) or an unmodified 4JK tumor (moderate expression of MHC class I) had significant but equal therapeutic efficacy. Although the in vitro growth rate of tumor cell lines was unaffected by the insertion of the mouse IFN cDNA, their in vivo (s.c.) growth rates were significantly slower than those of the nontransduced tumors. Thus, after retroviral transduction of the murine IFN cDNA into a nonimmunogenic tumor with a very low level of surface expression of MHC class I, modified tumor cells could elicit therapeutic T cells from DLN capable of successfully treating established pulmonary metastases upon adoptive transfer. This strategy significantly confirms previous observations on the potential therapeutic effects of gene modification of tumor cells with IFN and extends the realm of therapeutic possibilities to include the use of DLN cells for the development of T-cell based immunotherapies against nonimmunogenic human tumors.  相似文献   

18.
Summary A comparative conformational analysis of two short pseudopeptides with ETB receptor affinity has been performed by molecular modelling and NMR techniques. This analysis aimed to get insight into probable biorelevant conformations and pharmacophoric patterns necessary for an efficient interaction with the receptor. Thus, it was shown that the two compounds can adopt -turn (or -turn-like) conformations, based on which the synthesis of particular, more rigid analogs might be proposed. The results obtained should prove valuable in a strategy aiming to design new endothelin antagonists following a peptide to non-peptide approach.  相似文献   

19.
We previously characterized the expression of CD80 in different murine head and neck squamous cell carcinoma (HNSCC) clones derived following tumor progression in the absence of T cell–mediated immunity in severe combined immunodeficient (SCID) mice. We found that HNSCCs that did not express CD80 grew as progressors, while those that expressed CD80 were regressors when grown in immune-competent animals. In the present study, we characterized expression of a repertoire of immunoregulatory cytokines in these HNSCC lines, and found that HNSCCs that express cytokines IL-1, IL-6, and GM-CSF do not express CD80, suggesting the hypothesis that these cytokines may down-modulate expression of CD80. Cytokine-conditioned medium from progressor HNSCC and recombinant IL-1, IL-6, and GM-CSF caused a reduction of CD80 expression in regressor HNSCCs without affecting proliferation. Conversely, the decrease in CD80 expression in progressor HNSCCs could be restored by IFN-, a known inducer of CD80 expression. These data strongly suggest that high levels of cytokines IL-1, IL-6, and GM-CSF expressed by tumor cells can down-regulate CD80 expression in HNSCC, and that IFN- can independently stimulate expression. These data provide evidence for a novel mechanism of cytokine-mediated down-modulation of CD80 during malignant progression of HNSCC that can be restored by IFN-.  相似文献   

20.
Bacteria, yeasts, and molds which grew in a medium containing a synthetic lignin — a dehydrogenation polymer (DHP) of coniferyl alcohol — as a sole carbon source, were isolated from soil. One fungus, Fusarium solani M-13-1, was found to degrade the DHP most vigorously among the isolated organisms. It was shake-cultured in a medium containing dehydrodiconiferyl alcohol (DHCA) (I), an important lignin model compound, and the following six metabolic products were isolated and identified: 1) Phenylcoumaran--aldehydic (II) and -carboxylic compounds, 2) phenylcoumaran--aldehydic compound (IV), formed by release of a 2-carbon fragment from the phenylcoumaran--carboxylic compound, 3) 5-acetylvanillyl alcohol (V), formed by cleavage of the coumaran ring and reduction of the -aldehyde group, 4) 5-carboxyvanillyl alcohol (VI), formed by subsequent oxidation of the acetyl group, and 5) the -ether of DHCA (VII), considered to be a by-product. A degradation pathway for DHCA was proposed on the basis of these metabolic products.Non-Standard Abbreviations DHP dehydrogenation polymer - DHCA dehydrodiconiferyl alcohol - DDQ dichlorodicyano-p-benzoquinone - DDHQ dichlorodicyano-p-hydroquinone - Ar aromatic - TLC thin layer chromatography - GC-MS gas chromatography-mass spectrometry  相似文献   

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