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1.
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   

2.
Bulk populations of T-cell receptor (Tcr) -expressing splenocytes from different inbred strains of mice were examined for the diversity of Tcr proteins. Immunoprecipitations with anti-C1/2, anti-C4, and anti-V1 sera demonstrated that splenocytes from B10.BR, C57BL/6, and C57L strains of mice expressed the same array of Tcr proteins, namely V1-C2, V1-C4, and V2-C1, although the Tcr heterodimers observed for each of these strains were biochemically distinct. Examination of bulk splenic Tcr heterodimers from several other inbred strains of mice demonstrated that each of the strains could be categorized into one of three basic phenotypes. For several reasons, the differences observed between the strains appeared to be solely dependent on polymorphisms of the Tcrg loci. First, F1 mice co-expressed both parental Tcr phenotypes. Second, the distinguishing polymorphism between mice of phenotype 1 and phenotypes 2 or 3 was due to the presence of an N-linked glycosylation site within the Tcrg-C1 gene segment, previously described for BALB.B and C57BL/6 Tcrg-C1 genes. Finally, the V1-C4 polymorphism between mice of phenotype 3 and phenotypes 1 or 2 was due to differences in core protein size. Furthermore, the three defined Tcr chains were expressed independently of the major histocompatibility complex (MHC) haplotype. Although no striking qualitative differences in Tcr heterodimers were observed between strains (including those with autoimmune disorders), a quantitative difference in the relative amount of C4-encoded proteins was observed on Tcr splenocytes from both newborn euthymic and adult athymic mice when compared to adult Tcr splenocytes from euthymic mice. These results demonstrate that genetic polymorphisms exist among different mouse strains and suggest that selective developmental pressures may govern Tcr expression. Offprint requests to: J. A. Bluestone  相似文献   

3.
Summary We have previously reported that the combination of murine recombinant interferon (Mu-rIFN) with murine recombinant interferon (Mu-rIFN) provided greater inhibition of tumor growth than did each one alone in MethA-bearing mice. In the present study the effect of addition of human recombinant interleukin-2 (Hu-rIL-2) to the combination of Mu-rIFN with Mu-rIFN on tumor growth in BALB/c mice bearing syngeneic MethA fibrosarcoma was examined. Low doses of Hu-rIL-2 (5 × 103 U or 5 × 104 U at 3-day intervals) showed no antitumor activity, while a high dose of Hu-rIL-2 (5 × 105 U) showed profound growth inhibition. The administration of IL-2 (ranging between 5 × 103 U and 5 × 105 U) in addition to the combination of IFN and IFN showed more augmented antitumor effects in a dose-dependent manner. Furthermore, the simultaneous administration of IL-2, IFN and IFN had more effective therapeutic activity, compared with the sequential administration of interferons and IL-2. These findings indicated that IL-2 in combination with IFN and was effective for cancer treatment.  相似文献   

4.
We have isolated an unusual T cell receptor chain cDNA clone (7.1) from a library made from RNA derived from adult thymus of C57BL/Ka mice. This cDNA clone corresponds to the appropriately processed C1 constant region exons preceded by 1.5 kb of J-C1 intron. The 7.1 coding region is extremely homologous to the C1 gene of BALB/c mice, differing at the protein level by a single deletion (alanine 139) and a single substitution. This latter change eliminates the sole N-linked sugar attachment site, providing a basis for strain-specific glycosylation patterns. The J-C1 intronic region contains two DNA segments (termed J1 and J2) that are highly reminiscent of joining (J) segments; both have potentially functional recombination and donor splice sequences flanking an open reading frame. Northern analysis suggests that 7.1 may be derived from a large, variable region-containing precursor.  相似文献   

5.
The receptor with high affinity for immunoglobulin E (FcERI) is a key molecule in triggering the allergic reaction. It is tetrameric complex of one subunit, one subunit, and two disulfide-linked subunits. This receptor is present exclusively on mast cells and basophils. Molecules identical to the subunit of FcRI also form cell surface complex with other Fc receptors such as mouse FcRIIa in macrophages and most probably with human FcRIII (CD16) in natural killer (NK) cells. Here we show by in situ hybridization that the human genes for the (FCER1A) and subunits (FCER1 G) of FcERI and the gene for FcRIII (FCGR3, CD16) are located on human chromosome band 1823.  相似文献   

6.
Summary A comparative study of the antitumor effect of murine recombinant interferon() Mu-rIFN() and murine recombinant interferon() Mu-rIFN() on B16-F10 melanoma was conducted. Administration of Mu-rIFN() i.p. into C57BL/6 mice on days 1 to 7 produced a higher suppressive effect than Mu-rIFN() both on the growth of s.c. implanted tumor and on the formation of artificial pulmonary metastasis. Pharmacokinetic study of Mu-rIFN() demonstrated that high plasma levels were retained for a long time. In clonogenic assay, Mu-rIFN() at 1000 units/ml showed about 80% inhibition of colonies of B16-F10 melanoma. However, Mu-rIFN() hardly inhibited the colonies, even at 1000 units/ml. Augmentation of natural killer (NK) cytotoxicity was much greater with Mu-rIFN() than Mu-rIFN(), whereas Mu-rIFN() enhanced the cytotoxicity of peritoneal macrophages more strongly than Mu-rIFN(). Injection of Mu-rIFN() i.p. 1 day before tumor challenge also inhibited the formation of pulmonary metastasis of B16-F10 melanoma. However, pretreatment of mice with carrageenan significantly suppressed the inhibitory effect of Mu-rIFN(). From these results, it is suggested that the inhibitory effect of Mu-rIFN() on the tumor growth and metastases of B16-F10 melanoma is mediated partly by direct antitumor effect and partly by the activation of macrophages, and that the augmentation of NK activity contributes mainly to the antitumor effect of Mu-rIFN().  相似文献   

7.
Summary The -glucuronidase staining characteristics of isolated T cell populations and the T and T enriched fractions derived of them were studied. T lymphocytes were obtained from purified T lymphocytes by ox-IgG rosette sedimentation. The rosette-forming cells in the pellet were referred to as T lymphocytes, whereas the lymphocytes in the interface were referred to as T depleted or T lymphocytes. B cells were studied on rosetted mononuclear cells with either mouse erythrocytes or with Staphylococcus Aureus (Cowan I) bacteria, after a preceeding polyvalent anti-human Ig treatment of the cells. While B cells showed mostly no reactivity, T and T cells were respectively characterised by a dot-like and granular pattern of reactivity. These findings are in agreement with those observed by others after -naphthyl-acetate esterase or acid phosphatase staining. Within the T lymphocyte fraction, the T non-, non lymphocytes seemed to have a granular pattern of reactivity. The same staining pattern was found in non-B, non-T lymphocytes.  相似文献   

8.
    
A genomic clone encoding the -kafirin gene from sorghum was isolated and sequenced. A 2938 bp sequenced fragment includes an intronless open reading frame of 636 nucleotides encoding a putative polypeptide of 212 amino acids. Comparison of the deduced amino acid sequence of -kafirin with the published sequences of -prolamins of maize, and Coix revealed highly conserved domains. The N-terminal region of these proteins contains the conserved hexapeptide PPPVHL, which is repeated eight times in -zein, four times in -kafirin and three times in -coixin. The number of PPPVHL repeats accounts predominantly for the differences in the molecular weights of -prolamins. Several putative regulatory sequences common to the -kafirin and -zein genes were identified in both the 5 and the 3 flanking regions. Putative GCN4-like regulatory sequences were found at positions –192 and –476 in the 5 flanking region of -kafirin. In the 3 noncoding region, three putative polyadenylation signals, two AATAAT and one AATGAA, were found at positions + 658, + 716, and + 785, respectively. In order to investigate the role of the putative GCN4-like motifs and other possible cis-acting element(s) of the -kafirin promoter, a series of deleted and chimeric promoter constructs were introduced into maize, Coix and sorghum tissues by particle bombardment. Histochemical analysis of -glucuronidase (GUS) activity in different tissues indicated that the element(s) responsible for tissue specificity is probably located in the 285-bp proximal region of the promoter, while the remaining promoter sequence seems to carry the element(s) responsible for the quantitative response.The nucleotide sequence data reported in this paper appear in the EMBL/GenBank/DDBJ Nucleotide Sequence Databases under the accession number X62480  相似文献   

9.
Purification and properties of gammagamma-enolase from pig brain   总被引:1,自引:0,他引:1  
Isoelectric focusing revealed three enolase isoforms in pig brain, which were designated as - (pI = 6.5), - (pI = 5.6), and -enolase (pI = 5.2). The pI of purified -enolase was also 5.2. The -enolase isoform of enolase was purified from pig brain by a purification protocol involving heating to 55°C for 3 min, acetone precipitation, ammonium sulfate precipitation (40%–80%), DEAE Sephadex ion-exchange chromatography (pH 6.2), and Sephadex G200 gel filtration. The final specific activity was 82 units/mg protein. As with other vertebrate enolases, -enolase from pig proved to be a dimer with a native mass of 85 kDa and a subunit mass of 45 kDa. The pH optimum for the reaction in the glycolytic direction is 7.2. The K m values for 2-PGA, PEP, and Mg2+ were determined to be 0.05, 0.25, and 0.50 mM, respectively, similar to K m values of other vertebrate enolases. The amino acid composition of pig -enolase, as determined by amino acid analysis, shows strong similarity to the compositions of -enolases from rat, human, and mouse, as determined from their amino acid sequences. Despite the differences seen with some residues, and considering the ways that the compositions were obtained, it is assumed that pig -enolase is more similar than the composition data would indicate. Moreover, it is likely that the sequences of pig -enolase and the other -enolases are almost identical. Li+ proved to be a noncompetitive inhibitor with either 2-PGA or Mg2+ as the variable substrate. This enolase crystallized in the monoclinic space group P2, or P21. An R symm <5% was obtained for data between 50 and 3.65 Å, but was a disappointing 30% for data between 3.65 and 3.10 Å, indicating crystal disorder.  相似文献   

10.
    
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   

11.
Polyclonal antibodies to mouse - and /-caseins were raised in rabbits. These antibodies display tissue- and species specificity as shown by immunoblotting. Immunohistochemical analyses demonstrate that both - and /-caseins were synthesized and secreted from virtually all lactating mammary epithelial cells, in a pattern very similar to that of the mouse -lactalbumin. Residual amounts of caseins were located also in the apical surface of epithelial cells surrounding the ducal lumen of virgin mammary gland sections. In contrast to the significant level of -casein in the milk, the amount of this protein compared to - or -caseins was extremely low in medium conditioned for 24 h by mammary explants of mid-pregnant mice immediately after explantation or after 4 days.  相似文献   

12.
    
-Crystallin is a common lens protein of most vertebrate eye lenses and the major protein component in lenses of fishes and in many mammalian species during embryonic and neonatal stages. To facilitate the structural characterization of -crystallin possessing extensive charge heterogeneity, a cDNA mixture was constructed from the poly(A)+ mRNA isolated from shark eye lenses, and amplification by polymerase chain reaction (PCR) was carried out to obtain cDNAs encoding multiple shark -crystallins. Sequencing analysis of multiple positive clones containing PCR-amplified inserts revealed the presence of a multiplicity of isoforms in the -crystallin class of this cartilaginous fish. It was of interest to find that two shark cDNA sequences coexist, one encoding -crystallin (M1) of high methionine content (15.5%) and the other encoding one (M2) of low methionine content (5.1%), each corresponding to the major teleostean and mammalian -crystallins, respectively. Comparison of protein sequences encoded by these two shark cDNAs with published sequences of -crystallins from mouse, bovine, human, frog, and carp lenses indicated that there is about 61–80% sequence homology between different species of the piscine class, whereas only 47–66% is found between mammals and shark. A phylogenetic tree constructed on the basis of sequence divergence among various -crystallin cDNAs revealed the close relatedness between shark M2-crystallin and mammalian -crystallins and that between shark M1 and teleostean -crystallins. The results pointed to the fact that ancestral precursors of -crystallins were present in the sharp lens long before the appearance of modern-day mammalian and teleostean -crystallins.  相似文献   

13.
Using an immunoblotting technique and goat antihuman C4, we observed five distinct electrophoretic variants of C4 in a panel of 60 random dogs. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of immunoprecipitated C4 showed that dog C4 is composed of three polypeptide subunit chains (, , and ) and that structural variability occurs within the - and -chain regions. Two distinct molecular weight forms of both the C4- ( A and B) and C4-( A and B) chain were detected. The variant forms of C4 and C4 were found in association with particular C4 allotypes.  相似文献   

14.
We report the identification by two hybrid screens of two novel similar proteins, called Arabidopsis thaliana gamma carbonic anhydrase like1 and 2 (AtCAL1 and AtCAL2), that interact specifically with putative Arabidopsis thaliana gamma Carbonic Anhydrase (AtCA) proteins in plant mitochondria. The interaction region that was located in the N-terminal 150 amino acids of mature AtCA and AtCA like proteins represents a new interaction domain. In vitro experiments indicate that these proteins are imported into mitochondria and are associated with mitochondrial complex I as AtCAs. All plant species analyzed contain both AtCA and AtCAL sequences indicating that these genes were conserved throughout plant evolution. Structural modeling of AtCAL sequences show a deviation of functionally important active site residues with respect to CAs but could form active interfaces in the interaction with AtCAs. We postulate a CA complex tightly associated to plant mitochondrial complex.  相似文献   

15.
Summary DNA polymorphisms in the human immunoglobulin gamma () region have been studied in random Arabo-Berber Tunisians and in a large Tunisian Berber kindred. Haplotypes have then been designated, based on variation in the BamHI restriction fragments containing the C1, C2, C4, and C genes. Two new haplotypes, in addition to the four previously described, have been observed. These new haplotypes, designated H5 and H6, were confirmed by family studies. The H5 haplotype was associated with black African Gm haplotypes · (Gm1,17;..;5,6,11 and Gm1,17;..;5,11) (Gma,z;..;blc3bo and Gma,z;..;blbo) and probably represents a common haplotype in the black population. The haplotype H6 may be derived from H5. One of 39 random Tunisians was homozygous for a multigene deletion. DNA polymorphisms of the C genes, in conjuction with Gm markers, provide highly variable genetic markers important for the characterization of human populations.  相似文献   

16.
Protein Phosphatase-1 is phosphorylated in vitro by cdc2-cyclin B (Villa-Moruzzi, FEBS Lett 304: 211-215, 1992). In the present study we show that all the three Phosphatase-1 isoforms, , 1, , are phosphorylated by cdc2-cyclin B. Phosphorylation is specific for this kinase and involves a C-terminal Thr. This site is most likely Thr 320 in a (shown by others to be phosphorylated also by cdc2-cyclin A). Such Thr is conserved in 1, and in the testis-specific 2, and is the only Thr that fits the cdc2-consensus sequence in the C-terminal region. Phosphorylation of Phosphatase-1 purified from skeletal muscle, which is a mixture of the a, 1 and isoforms, is up to 0.4 mol/mol and induces 30-35% enzyme inactivation. Following tryptic proteolysis each isoform yields a distinct phosphopeptide map. This is in agreement with the different sequences of the isoforms in the C-terminal regions and may be useful to distinguish the isoforms lts suggest that all the Phosphatase-1 isoforms may be potentially regulated at M-phase.  相似文献   

17.
Transgenic animals secreting individual chains and assembled fibrinogen were produced to evaluate the capacity of the mammary gland for maximizing assembly, glycosylation and secretion of recombinant human fibrinogen (rhfib). Transgenes were constructed from the 4.1kbp murine Whey Acidic Protein promoter (mWAP) and the three cDNAs coding for the A, B and fibrinogen chains. Transgenic mice secreted fully assembled fibrinogen into milk at concentrations between 10 and 200 g/ml, with total secretion of subunits approaching 700 g/ml in milk. Partially purified fibrinogen was shown to form a visible and stable clot after treatment with human thrombin and factor XIII. The level of assembled fibrinogen was proportional to the lowest amount of subunit produced where both the B and chains were rate limiting. Both the B and chains were glycosylated when co-expressed and the degree of saccharide maturation was dependent on expression level, with processing preferred for chains over B chains. Also, the subunit complexes 2, A2 and the individual subunits A, B and were found as secretion products. When the B was secreted individually, the glycosylation profile of the molecule was of a mature complex saccharide indicating recognition of the molecule by the glycosylation pathway without association with other fibrinogen chains. To date secretion of B chain has been not observed in any cell type, suggesting that the secretion pathway in mammary epithelia is less restrictive than that occurring in hepatocytes and other cells previously used to study fibrinogen assembly.  相似文献   

18.
Of 147 microorganisms isolated from a loamy sand, 71 showed good growth with lindane (-1,2,3,4,5,6-hexachlorocyclohexane) and produced chloride in an aqueous medium. Thirteen soil microorganisms were selected to study the utilization of lindane. Lindane was metabolized by the microbes to -2,3,4,5,6-pentachloro-1-cyclohexene (-PCCH), -3,4,5,6-tetrachloro-1-cyclohexene (-TCCH), -3,4,5,6-tetrachloro-1-cyclohexene (-TCCH), -3,4,5,6-tetrachloro-1-cyclohexene (-TCCH), and pentachlorobenzene (PCB). Cells of Pseudomonas sp. No. 62 grown on lindane simultaneously adapted to -PCCH, -TCCH, -TCCH, -TCCH, PCB, 1,2,3,4-tetrachlorobenzene (1,2,3,4-TCB) and 1,2,4,5-tetrachlorobenzene (1,2,4,5-TCB). The bacteria degraded each of these chemicals at least partially as indicated by an increased rate of oxygen consumption.Abbreviations Lindane -1,2,3,4,5,6-hexachlorocyclohexane - -PCCH -2,3,4,5,6-pentachloro-1-cyclohexene - -TCCH -3,4,5,6-tetrachloro-1-cyclohexene - -TCCH -3,4,5,6-tetrachloro-1-cyclohexene - -TCCH -3,4,5,6-tetrachloro-1-cyclohexene - PCB pentachlorobenzene - 1,2,3,4-TCB 1,2,3,4-tetrachlorobenzene - 1,2,3,5-TCB 1,2,3,5-tetrachlorobenzene - 1,2,4,5-TCB 1,2,4,5-tetrachlorobenzene - 1,2,3-tCB 1,2,3-trichlorobenzene - 1,2,4-tCB 1,2,4-trichlorobenzene - 1,3,5-tCB 1,3,5-trichlorobenzene - 1,2-DCB 1,2-dichlorobenzene - 1,3-DCB 1,3-dichlorobenzene - 1,4-DCB 1,4-dichlorobenzene - MCB monochlorobenzene Contribution No. 631, Research Institute, Agriculture Canada, University Sub Post Office, London, Ontario N6A 5B7  相似文献   

19.
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   

20.
Replacement of unlabeled -butyrobetaine with -[2,3,4-2H6]butyrobetaine has a profound effect on the stoichiometry between decarboxylation of 2-oxoglutarate and hydroxylation in the reaction catalyzed by human -butyrobetaine hydroxylase. The ratios between decarboxylation and hydroxylation are 1.16 with Unlabeled and 7.48 with deuterated -butyrobetaine as substrate. From these ratios an internal isotope effect of 41 has been calculated. DV in the overall reaction measured as 2- oxoglutarate decarboxylation is 2.5 and DV/K is 1.0. For -butyrobetaine hydroxylase fromPseudomonas sp. AK 1, 2-oxoglutarate decarboxylation exceeds hydroxylation with 10% when deuterated -butyrobetaine is used. No excess was found with unlabeled substrate and no internal isotope effect could be calculated. DV for the bacterial enzyme is 6.  相似文献   

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