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1.
Establishment of internal-image anti-idiotype monoclonal antibodies to a human antibody to lung cancer 总被引:4,自引:0,他引:4
Hiroaki Saito Masaru Taniguchi Toshio Fukasawa Yutaka Yamaguchi T. Fujisawa 《Cancer immunology, immunotherapy : CII》1997,44(2):83-87
Internal-image anti-idiotype antibodies are expected to enhance anticancer effector mechanisms in vivo. The objective of
this study was to establish hybridomas producing anti-idiotype monoclonal antibodies against a human monoclonal antibody (hmAb)
4G12 that reacts strongly with lung squamous cell carcinomas. BALB/c female mice 6 weeks old were immunized with 4G12. Splenocytes
were hybridized with P3U1 cells and hybrid cells secreting anti-4G12 hmAb were cloned. Two clones reacted with 4G12 hmAb but
not with 3H12 IgM hmAb, human IgM, human serum or fetal calf serum. These two Ab2 antibodies (IgG1κ) 2B12 and 2H1 demonstrated
91.5% and 90.3% inhibition in their reactivity with radiolabelled 4G12 on PC10 cells, indicating that 2B12 and 2H1 antibodies
were of the Ab2β type. In criss-cross inhibition assays, the binding of 2B12 or 2H1 to 4G12 was not inhibited by 2H1 or 2B12.
Thus 2B12 and 2H1 were thought to recognize the different epitopes on the antigen-binding sites. Antisera against 2B12 and
2H1 demonstrated specific reactivity to PC10 cells. The two Ab2β antibodies, 2B12 and 2H1, express internal images of lung
squamous cell carcinoma recognized by the 4G12 antibody and may be useful for cancer immunotherapy.
Received: 20 September 1996 / Accepted: 2 January 1997 相似文献
2.
Lindsay Crickard Tahar Babas Sidharth Seth Peter Silvera Lilia Koriazova Shane Crotty 《PloS one》2012,7(11)
Smallpox (variola virus) is a bioweapon concern. Monkeypox is a growing zoonotic poxvirus threat. These problems have resulted in extensive efforts to develop potential therapeutics that can prevent or treat potentially lethal poxvirus infections in humans. Monoclonal antibodies (mAbs) against smallpox are a conservative approach to this problem, as the licensed human smallpox vaccine (vaccinia virus, VACV) primarily works on the basis of protective antibody responses against smallpox. Fully human mAbs (hmAbs) against vaccinia H3 (H3L) and B5 (B5R), targeting both the mature virion (MV) and extracellular enveloped virion (EV) forms, have been developed as potential therapeutics for use in humans. Post-exposure prophylaxis was assessed in both murine and rabbit animal models. Therapeutic efficacy of the mAbs was assessed in three good laboratory practices (GLP) studies examining severe combined immunodeficiency mice (SCID) given a lethal VACV infection. Pre-exposure combination hmAb therapy provided significantly better protection against disease and death than either single hmAb or vaccinia immune globulin (VIG). Post-exposure combination mAb therapy provided significant protection against disease and death, and appeared to fully cure the VACV infection in ≥50% of SCID mice. Therapeutic efficacy was then assessed in two rabbit studies examining post-exposure hmAb prophylaxis against rabbitpox (RPXV). In the first study, rabbits were infected with RPVX and then provided hmAbs at 48 hrs post-infection, or 1 hr and 72 hrs post-infection. Rabbits in both groups receiving hmAbs were 100% protected from death. In the second rabbitpox study, 100% of animal treated with combination hmAb therapy and 100% of animals treated with anti-B5 hmAb were protected. These findings suggest that combination hmAb treatment may be effective at controlling smallpox disease in immunocompetent or immunodeficient humans. 相似文献
3.
Mutants having impaired protein synthesis, that is cycloheximide-sensitive mutants of a citric-acid-hyper-accumulating strain,
were induced from Aspergillus niger WU-2223L. Selection was on the basis of a presumption that the mutants should be more sensitive to cycloheximide than WU-2223L.
In shake culture without methanol as a promotor substance, seven mutants accumulated approximately 1.8–3.5 times as much citric
acid as WU-2223L. The best mutant, CHM I-C3, accumulated 69.4 mg citric acid/ml from 120 mg glucose/ml in shake culture without
methanol, this amount being 1.1 times the amount accumulated by WU-2223L with methanol. Furthermore, under the conditions
without methanol the mutants appeared to be more efficient than WU-2223L in employing the consumed glucose for the accumulation
of citric acid. It was also confirmed that CHM I-C3 exhibited a significantly increased level of intracellular NH+
4 accumulation. The addition of 2% (v/v) methanol or 20 μg cycloheximide/ml to the medium caused a remarkable increase of citric
acid accumulation by WU-2223L: about 3.1 and 2.4 times respectively. However, the addition of these substances produced negative
effects on citric acid accumulation by the mutants. With 2% (v/v) methanol, WU-2223L showed a remarkably decreased level of
protein accumulation but a substantially increased level of intracellular NH+
4 accumulation. However, these phenomena were also observed in CHM I-C3 without methanol. These results indicate that the intracellular
circumstances of the cycloheximide-sensitive mutants without methanol were similar to those of WU-2223L with methanol, and
that the impairment of protein synthesis contributed to increased citric acid accumulation by the mutants in the absence of
methanol.
Received: 21 November 1994 / Received last revision: 10 July 1995 / Accepted: 26 July 1995 相似文献
4.
L. Sajc G. Vunjak-Novakovic D. Grubisic N. Kovačević D. Vuković B. Bugarski 《Applied microbiology and biotechnology》1995,43(3):416-423
The production of anthraquinones by Frangula alnus Mill. plant cells was used as a model system to evaluate the performance of a liquid-liquid extractive product-recovery process.
The shake flask experiments have shown higher production of anthraquinones in cell suspension and flask cultures of calcium-alginate-immobilized
cells when silicone oil was incorporated into the medium, compared to a control without silicone oil. An external-loop air-lift
bioreactor, developed and designed for the production and simultaneous extraction of extracellular plant cell products, was
regarded as a four-phase system, with dispersed gas, non-aqueous solvent and calcium-alginate-immobilized plant cells in Murashige
and Skoog medium. Continuous extraction of anthraquinones by silicone oil and n-hexadecane inside the bioreactor resulted in 10–30 times higher cell productivity, compared to that of immobilized cells
in a flask. Based on the mixing pattern, immobilized biocatalyst extraparticle and intraparticle diffusional constraints and
the kinetics of growth, substrate consumption and product formation, a mathematical model was developed to describe the time
course of a batch plant cell culture. The model showed satisfactory agreement with four sets of shake flask experiments and
three bioreactor production cycles.
Received: 18 March 1994/Received revision: 20 September 1994/Accepted: 28 September 1994 相似文献
5.
L. Li T. A. Freier P. A. Hartman J. W. Young D. C. Beitz 《Applied microbiology and biotechnology》1995,43(5):887-892
A resting-cell assay was established to evaluate the cholesterol reductase activity of Eubacterium coprostanoligenes ATCC 51222. Cell suspensions from cholesterol-free media rapidly reduced cholesterol to coprostanol. Optimal assay conditions
in a 1-ml reaction mixture were determined to be up to 1 h of incubation and up to 0.25 mg bacterial protein/assay with at
least 1 mM cholesterol as substrate. The cholesterol reductase activity in cells decreased as a function of storage time at
22°C, 4°C and −20°C. Filling the headspace of the reaction mixture with H2 increased the activity about 20%. Optimal cholesterol reductase activity occurred at pH 7.5 in sodium phosphate buffer. Pyruvate
and reducing agents in the buffer increased the activity. This study has validated assay conditions for determination of cholesterol
reductase activity in resting cells of E. coprostanoligenes.
Received: 2 August 1994/Received revision: 15 November 1994/Accepted: 8 December 1994 相似文献
6.
W. H. Schwarz K. Bronnenmeier B. Krause F. Lottspeich W. L. Staudenbauer 《Applied microbiology and biotechnology》1995,43(5):856-860
The gene arfB encoding α-L-arabino-furanosidase B of the cellulolytic thermophile Clostridium stercorarium was expressed in Escherichia coli from a 2.2-kb EcoRI DNA fragment. The recombinant gene product ArfB was purified by fast-performance liquid chromatography. It has a tetrameric
structure with a monomeric relative molecular mass of 52 00. The optima for temperature and pH are 70 °C and 5.0 respectively.
The enzyme appears to have no metal cofactor requirement and is sensitive to sulfhydryl reagents. It hydrolyzes aryl and alkyl
α-L-arabinofuranosides and cleaves arabinosyl side-chains from arabinoxylan (oat-spelt xylan) and from xylooligosaccharides produced
by recombinant endoxylanase XynA from the same organism. The identity of the N-terminal amino acid sequences indicates that
ArfB corresponds to the major α-arabinosidase activity present in the culture supernatant of C. stercorarium.
Received: 30 September 1994/Received revision: 24 November 1994/Accepted: 16 December 1994 相似文献
7.
Strain 2-79 is a biocontrol agent againsttake-all, an important disease of wheat caused by Gaeumannomyces graminis var. tritici. In the rhizosphere, it produces the antibiotic phenazine 1-carboxylic acid (PCA) as the primary means of disease suppression.
One barrier to commercial use of phenazine-producing pseudomonads, like strain 2-79, is the lack of liquid-culture technology
for mass production. For instance, there is little published research concerning the impact of liquid-culture secondary metabolism
on the biocontrol qualities of the cell harvest, i.e., efficacy, phytotoxicity, and storage survival. Yet it is important
to know whether the fermentation process should be designed to enhance or eliminate secondary metabolite accumulation. To
enable future exploration of this issue, we identified liquid-culture parameters that could be manipulated to controlthe phenazine
productivity of strain 2-79. Our results indicated that PCA accumulation was very sensitive to the culture pH and temperature.
It was possible to produce large cell populations with either high or low phenazine productivity by choosing to control culture
pH at 7 and 8 respectively. Although high cell accumulations were achieved over the broad 25–34°C range studied, high, moderate,
or low PCA productivities were observed at 25–27°C, 29–32.5°C, or 34°C respectively. When pH was controlled at 7, specific
PCAproductions at 25°C could be modulated by the choice of carbon source supplied. PCA accumulation per unit biomass reached
0.31 g/g on glucose, 0.16 g/g on glycerol and xylose, and only 0.09 g/g on fructose. Although the nitrogen source was also
tested as a variable, it had little influence on culture PCA productivity under controlled pH.
Received: 12 July 1994 / Received revision: 8 October 1994/Accepted: 22 November 1994 相似文献
8.
Masahiro Matsuda Shiro Shigeta Koichi Okutani 《Marine biotechnology (New York, N.Y.)》1999,1(1):68-73
A marine Pseudomonas species WAK-1 strain simultaneously produces extracellular glycosaminoglycan and sulfated polysaccharide. Among the antiviral
activities tested for these polysaccharides, the latter showed anti-HSV-1 activity in RPMI 8226 cells (50% effective concentration
is 1.4 μg/ml). Oversulfated derivatives of these polysaccharides prepared by dicyclohexylcarbodiimide-mediated reaction for
both polysaccharides showed antiviral activities against influenza virus type A (for glycosaminoglycan, 50% effective concentration
is 11.0 μg/ml; for another, 2.9 μg/ml). Glycosaminoglycan, sulfated polysaccharide, and their chemically synthesized oversulfated
derivatives did not show antiviral activities against influenza virus type B and human immunodeficiency virus type 1. No cytotoxicity
of these products was noted against host cells at the 50% cytotoxic concentration of 100 μg/ml, except that naturally occurring
sulfated polysaccharide had 50% cytotoxicity against MT-4 cells at 8–21 μg/ml.
Received May 1, 1998; accepted July 24, 1998. 相似文献
9.
An industrial strain of Penicillium chrysogenum was subjected to carbon or nitrogen limitation in a chemostat and the response monitored in terms of the “classical” indicators
of autolysis (biomass decline and ammonia release), culture degradation (as measured by image analysis) and by obtaining profiles
for three classes of proteases implicated in autolysis. Under both sets of conditions (carbon or nitrogen limitation), once
started, autolysis involved a succession of different protease activities. The first stages of the process of autolysis in
starved chemostat cultures was associated with peaks in the activities of both serine and aspartyl proteases, coinciding with
the mobilisation of endogenous energy reserves. Conversely, a peak in the activity of metalloproteases was associated with
the later stages of autolysis, perhaps occurring in response to depletion of endogenous energy reserves; the activity of these
enzymes led to gross culture degradation, disintegration of ordered mycelial structures and signalled the end of metabolic
activity (respiration) within the culture. These findings indicate that strategies intended to control/regulate autolysis
in large-scale industrial fungal cultures might profitably be focused on regulation of the activity of key classes of proteases
involved in the series of events leading to culture degradation.
Received: 14 June 1999 / Received revision: 16 September 1999 / Accepted: 17 September 1999 相似文献
10.
We investigated the optimum conditions for the formation of nitrile hydratase (NHase), which acts on indole-3-acetonitrile,
in Agrobacterium tumefaciens. Good inducers for enzyme formation have been found to be roughly classified into three representative types of amides such
as pivalamide, crotonamide and ɛ-caprolactam. When the strain was cultivated in the optimum culture medium containing ɛ-caprolactam
as an inducer, in particular, the specific activity of NHase in the culture was 13 000 times higher than that without addition
of amides, nitriles or acids. In this case, NHase formed accounted for 12% of the total cellular soluble protein. The purified
NHase did not act on ɛ-caprolactam, and ɛ-caprolactam was not degraded during the cultivation by the strain, suggesting that
ɛ-caprolactam seems to keep driving the NHase induction mechanism.
Received: 3 March 1995/Received revision: 13 July 1995/Accepted: 7 September 1995 相似文献
11.
N. Barron R. Marchant L. McHale A. P. McHale 《Applied microbiology and biotechnology》1995,43(3):518-520
The thermotolerant yeast strain, Kluyveromyces marxianus IMB3, was found to be capable of ethanol production during growth at 45°C on media containing milled paper and exogenously
added commercial cellulase. At maximum achievable cellulose concentrations in shake-flask cultures, ethanol production increased
to 6.6 g/l at 45°C, representing an overall level of conversion of 21% of the maximum theoretical yield. Subsequent studies
involving variations in added cellulase concentrations to the batch systems demonstrated that ethanol yields could be increased
to 10 g/l at 45°C, which represented 39% of the maximum theoretical yield. As a result of ethanol production at 45°C in the
systems examined, we suggest that the thermotolerant ethanol-producing yeast strain K. marxianus represents a novel candidate for use in simultaneous saccharification and conversion of the resulting substrates to ethanol.
Received: 9 June 1994/Received revision: 8 August 1994/Accepted: 12 August 1994 相似文献
12.
B. E. Whitman J. R. Mihelcic D. R. Lueking 《Applied microbiology and biotechnology》1995,43(3):539-544
A model system was developed for evaluating naphthalene biosorption based on the use of a mutant (strain TG-5 Nah-) derived from a naphthalene-degrading Pseudomonas fluorescens isolate. Cells of strain TG-5 had a sorptive capacity for naphthalene (partition coefficient of 380 cm3/g) significantly higher than a soil with a 5.1% organic carbon content (partition coefficient of 41 cm3/g). However, experimental results and a mass balance model demonstrated that, in soil systems of high organic carbon content,
the mass of naphthalene associated with biological solids is insignificant. In contrast, in a soil system of nonsorptive Ottawa
sand, up to 10% of the initial naphthalene was demonstrated experimentally, and by modeling, to be associated with cells of
strain TG-5.
Received: 6 June 1994/Received revision: 12 September 1994/Accepted: 28 September 1994 相似文献
13.
S. A. C. Jorge C. Hera A. M. M. Spina R. C. Moreira J. R. R. Pinho C. F. M. Menck 《Applied microbiology and biotechnology》1996,46(5-6):533-537
The hepatitis B virus surface antigen (HBsAg) gene, under control of the inducible mouse metallothionein I gene promoter,
was inserted in an expression vector based on the Epstein-Barr virus (EBV). This vector was introduced into human cells by
DNA transfection and clones were selected for their resistance to hygromycin B. The recombinant EBV vector replicates efficiently
as an episome in human cells and approximately six copies per cell were found in one clone of hygromycin-B-resistant cells.
These cells produce high levels of HBsAg in the presence of metals. The protein is mainly found in the cell medium, suggesting
that the HBsAg is secreted from the cells.
Received: 25 February 1996 / Received revision: 21 June 1996 / Accepted: 15 July 1996 相似文献
14.
The effect of calcium on flavanol production in cell suspension cultures of Polygonum hydropiper 总被引:5,自引:0,他引:5
Cultured Polygonum hydropiper cells maintained in Murashige and Skoog (MS) medium supplemented with 10–6
m 2,4-D, 10–6
m kinetin, 0.1% casamino acids and 3% sucrose were transferred to medium containing a higher concentration of calcium chloride
(15 mm). The content of flavanols in the cells on the 6th day was approximately twice that of the control culture (31.9–60.7 mg/g
dry wt). However, the contents of other secondary metabolites such as chlorogenic acid and gallic acid were not changed. The
levels of flavanols in the culture medium remained unchanged throughout the 21-day culture period. Of the the inorganic components
supplemented to the culture medium , only elevated levels of calcium chloride induced an increase in flavanol contents of
the cells. The results indicated that the elevated concentration of calcium in the culture medium played an important role
in activating the accumulation of flavanols.
Received: 4 June 1998 / Revision received: 30 October 1998 / Accepted: 29 November 1998 相似文献
15.
This paper describes a general approach fordynamic model discrimination for continuous cultures and presents dynamic models
for pure cultures of E. coli and C. utilis obtained using the method. For each pure culture system, four candidate models representing various levels of structure were
considered. All models reduce to Monod growth kinetics at steady state. An optimized set of multivariable step inputs in selected
manipulative variables was used to discriminate between candidate models. The models that best predicted the dynamic behavior
were selected by comparison of model predictions with experimental data. Two discrimination functions were compared in terms
of their ability to determine the optimal set of multivariable step inputs to discriminate between candidate models. Results
indicate that model discrimination based on maximizing the minimum absolute difference between any two models for a given
set of inputs possessed good potential for discrimination between candidate models. Models selected for E. coli andC. utilis from the model discrimination work arepresented and compared with experimental data.
Received: 24 May 1994/Received revision: 28 September 1994/Accepted: 5 December 1994 相似文献
16.
Two plant-growth-promoting bacteria, Azospirillum brasilense Cd and Pseudomonas fluorescens 313, immobilized in 1983 in two types of alginate-bead inoculant (with and without skim-milk supplement) and later dried
and stored at ambient temperature for 14 years, were recovered in 1996. The population in each type of bead had decreased,
yet significant numbers survived (105–106 cfu/g beads). Population numbers depended on the bead type and the three independent bacterial counting methods: the conventional
plate-count method, indirect enzyme-linked immunosorbent assay and the limited-enrichment technique. Both bacterial species
retained several of their original physiological features. When inoculated onto wheat plants, both species colonized and produced
plant-growth effects equal to those of the contemporary strain from a culture collection or to their own 1983 records. This
study showed that bacteria can survive in alginate inoculant over long periods.
Received: 1 May 1998 / Received revision: 24 August 1998 / Accepted: 3 September 1998 相似文献
17.
G. Zellner E. Feuerhake H. J. Jördening A. J. L. Macario E. Conway de Macario 《Applied microbiology and biotechnology》1995,43(3):566-571
A denitrifying bacterial biofilm population established on a polypropylene substratum of a fixed-film reactor was characterized
by microscopy, scanning electron microscopy and immunofluorescence after 120 days of operation. The reactor, operated at pH
7.0, 22°C, and −180 mV with synthetic wastewater containing methanol/nitrate, achieved a denitrification rate of 0.24 mol
NO-
3 l-1 day-1 with a removal efficiency for nitrate of 95%–99% at an organic loading rate of 0.325 mol methanol l-1 day-1. The gas produced contained 2%–3% (v/v) methane and 3%–4% (v/v) carbon dioxide in addition to nitrogen. The biofilm contained
mainly cells of Methanobrevibacter arboriphilus antigenically related to strain DC, short, flagellated, gram-negatively staining rods of Pseudomonas sp. antigenically related to Pseudomonas stutzeri strain AN11, non-identified pink-pigmented rods and small lemon-shaped cells with mono- and bipolar appendages resembling
prosthecate Hyphomicrobium sp. The biofilm analysis provided evidence for a syntrophy between the denitrifying, methylotrophic, bacterial consortium
and hydrogenotrophic methanogens, which were identified by antigenic fingerprinting with 17 antibody probes.
Received: 11 July 1994/Received revision: 23 September 1994/Accepted: 28 September 1994 相似文献
18.
C. Ward A. M. Nolan K. O'Hanlon T. McAree N. Barron L. McHale A. P. McHale 《Applied microbiology and biotechnology》1995,43(3):408-411
The thermotolerant, ethanol-producing yeast strain, Kluyveromyces marxianus IMB3, was shown to produce ethanol at 45°C on starch-containing media supplemented with a crude amylase preparation derived
from the thermophilic, filamentous fungus Talaromyces emersonii CBS 813.70. Ethanol production on media containing 4% (w/v) starch increased to a maximum of 15 g/l with 40 h, and this represented
74% of the maximum theoretical yield. Subsequent experimentation involving growth of both organisms in fermentations on starch-containing
media (4% w/v) demonstrated that the mixed-culture system was capable of ethanol production at 45°C with maximum yields at
12 g/l obtained with 65 h. The advantages associated with ethanol production by this system are discussed.
Received: 16 May 1994/Accepted: 22 October 1994 相似文献
19.
C. M. Hooijmans T. A. Abdin G. J. Alaerts 《Applied microbiology and biotechnology》1995,43(5):781-785
Lipid phosphate, which is a measure of viable biomass, was determined using biofilm samples from three different laboratory-scale
reactors. The analysis procedure proposed in the literature was modified and tested for suitability in experiments with biofilm
reactors. The microbial contents of the biofilms studied are compared in three types of reactor.
Received: 2 November 1994/Accepted: 23 January 1995 相似文献
20.
T. Kobayashi Y. Hakamada J. Hitomi K. Koike S. Ito 《Applied microbiology and biotechnology》1996,45(1-2):63-71
Alkalophilic Bacillus sp. KSM-K16 produced three alkaline proteases, as detected by polyacrylamide gel electrophoresis (PAGE). The major protease,
designated M protease, was recently purified to homogeneity and its properties were characterized. In the present study, two
minor proteases, designated H protease and N protease, were purified to homogeneity from cultures of this organism. H protease
had a molecular mass of 28 kDa, as estimated by sodium dodecyl sulfate/PAGE (SDS-PAGE) and its maximum activity against casein
was observed at pH 11.0 and at 55°C. N protease consisted of two polypeptide chains with molecular masses of 12.5 kDa and 14.5 kDa, as estimated by SDS-PAGE,
although it migrated as a single protein band during non-denaturing PAGE. Its maximum activity was observed at pH 11.0 and
at 60°C. The amino-terminal sequences of H protease and of the 14.5-kDa polypeptide of N protease were identical to that of M protease.
The electrophoretic relationship between the three enzymes was examined after they had been stored at different pH values
and at 5°C. M protease was converted to H protease more rapidly at pH 11 than at pH 8 or below, and H protease was converted to M protease
at pH 8 or below but not at pH 11. N protease appeared to be the autolytic product of the M and H proteases.
Received: 12 December 1994/Received last revision: 9 June 1995/Accepted: 31 July 1995 相似文献