To generate industrially applicable new host cell lines for antibody production with optimizing antibody-dependent cellular cytotoxicity (ADCC) we disrupted both FUT8 alleles in a Chinese hamster ovary (CHO)/DG44 cell line by sequential homologous recombination. FUT8 encodes an alpha-1,6-fucosyltransferase that catalyzes the transfer of fucose from GDP-fucose to N-acetylglucosamine (GlcNAc) in an alpha-1,6 linkage. FUT8(-/-) cell lines have morphology and growth kinetics similar to those of the parent, and produce completely defucosylated recombinant antibodies. FUT8(-/-)-produced chimeric anti-CD20 IgG1 shows the same level of antigen-binding activity and complement-dependent cytotoxicity (CDC) as the FUT8(+/+)-produced, comparable antibody, Rituxan. In contrast, FUT8(-/-)-produced anti-CD20 IgG1 strongly binds to human Fcgamma-receptor IIIa (FcgammaRIIIa) and dramatically enhances ADCC to approximately 100-fold that of Rituxan. Our results demonstrate that FUT8(-/-) cells are ideal host cell lines to stably produce completely defucosylated high-ADCC antibodies with fixed quality and efficacy for therapeutic use.

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We report here the identification of mouse betaklotho (betakl), which encodes a type I membrane protein with high resemblance to Klotho (KL). Both betaKL and KL consist of two internal repeats with homology to family 1 glycosidases, while these essential glutamates for the enzymatic activities were not conserved. The identical pattern of substitution and variation in the substituted amino acids between these two proteins indicate that they likely to form a unique family within the glycosidase family 1 superfamily. During mouse embryonic development, strong betakl expression was detected in the yolk sac, gut, brown and white adipose tissues, liver and pancreas, and in the adult, predominantly in the liver and pancreas. Despite the high structural similarity between betaKL and KL, their expression profiles were considerably different and betakl expression was not induced in kl-deficient mouse mutants.

The occurrence of giant edge localized modes (ELMs) in DIII-D has previously been correlated with the violation of the ballooning stability criterion at the plasma edge. These results are extended in the paper. It is demonstrated theoretically that flux surfaces near the separatrix of properly elongated and triangulated plasmas may be moved into the connection region between the first and second stability regions for ideal MHD ballooning modes, when q is high and the shear is low near the plasma surface. The edge flux surfaces are then predicted to have no limit to the sustainable pressure gradient. Experimentally, giant ELMs disappear in these highly shaped plasmas. However, the edge pressure gradient does not increase and ‘grassy’ ELM behaviour appears instead. These results lend further support to the hypothesis that giant ELMs in DIII-D are triggered by ideal ballooning mode instabilities, but they indicate that giant ELM and grassy ELM behaviour may arise from somewhat different mechanisms.

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In the toroidal plasma confinement devices using external helical conductors for forming the nested magnetic surfaces, such as heliotrons, torsatrons, and stellarators, the plasma equilibrium can be maintained without Ohmic-heating current. This property can, in principle, lead to the steady-state operation of a controlled thermonuclear reactor, and has led to recent efforts using injected energetic neutral beams 1 ' 2 and radio-frequency waves 2 * 3 to sustain the plasma in stellarators and heliotrons. A nearly currentfree plasma was recently reported 1 in the Wendelstein VII-A stellarator in which substantial ion heating was observed by neutral-beam injection. The nature of energy confinement in the experiment, however, has not been fully resolved because of the dominance of radiative loss in the experiment.This paper presents experimental results on confinement of a plasma initiated and heated by radio-frequency waves at the electron cyclotronresonance frequency in a heliotron configuration. In the afterglow regime the radiative loss is measured to be small and the energy loss rate of electrons is dominated by equipartition with ions. This allows a comparison with neoclassical theory.The Helotron-E device (major radius R = 2.2 m, average minor radius of plasma r p =0.2 m) is an asymmetric toroidal system with large rotational transform [I(0)/2TT = 0.5, i{r p )/2u = 2.2] and strong shear. The Z = 2 helical coils can produce a maximum magnetic field of 20 kG. The experiment was performed at 10 kG to match the electron cyclotron-resonance heating (ECRH) power available at 28 GHz. The microwave tube has a peak output power of 200 kW and pulse length of 10 msec. The cutoff density is 1.0 x 10 13 cm" 3 for the ordinary wave. The microwave output was in TE 02 circular mode, transmitted to the Heliotron-E by a 2.5-in.-diam waveguide. The radiated power consists of an almost equal mixture of ordinary and extraordinary waves. As shown in Fig. 1, the wave was launched from the low-field side. The ordinary wave was expected to be transmitted directly into the plasma and the extraordinary wave would be reflected at the righthand cutoff. It can be expected, however, that Confinement of a plasma initiated and heated by electron cyclotron-resonance-frequency waves has been studied in the Heliotron-E. The observed plasma parameters were T e * 500-100 eV, T t ^ 100 eV, n e = 4x lo 12 cm" 3 at B = 10 kG. The electron energy decay time was 40± 8 msec and the particle confinement time was estimated to be more than 70 msec. These results offer a considerable improvement in energy confinement over Ohmically heated plasmas.

Axonemal sliding involves both sliding velocity and the extent of sliding, that is how many doublets slide. It is clear that axonemes cannot beat if all doublets were to slide simultaneously, thus sliding extent is important. Using the turbidimetric assay of sliding disintegration of Tetrahymena axonemes, we examined the sliding extent and th effect of APD, ATP, and ATP analogs on the sliding extent. Of course, ATP is necessary to produce sliding disintegration, but ATP alone did not produce extensive sliding disintegration. The additions of higher ATP concentration even in the presence of ADP inhibited sliding disintegration. We also observed sliding disintegration using ribose-modified ATP analogs, anthraniloylATP, and methylanthraniloylATP. The extent of sliding disintegration was proportional to the analog concentration. Thus in contrast to ATP, higher analog concentration was not inhibitory. These results indicate that high ATP concentration acts to inhibit the extent of sliding disintegration and that ADP relieves this inhibition. We propose a model in which the affinity of of multiple cooperative active sites are regulated by the binding of ATP or ADP to a regulatory site. This model provides a mechanism by which nucleotides regulate the extent of sliding necessary for effective axonemal bending.

The world's newest quasi-axisymmetric stellarator CFQS is constructed as a joint project of the National Institute for Fusion Science, Japan and Southwest Jiaotong University, the People's Republic of China. The project is named "NSJP for CFQS". The CFQS has a major radius of 1 m, toroidal periods of 2, and aspect ratio of 4. The toroidal magnetic field strength will be increased up to 1 T. The CFQS equilibrium is characterized by low-aspect ratio and quasi-axisymmetry, having both natures of two-dimensional tokamak and three-dimensional stellarator. The CFQS offers new opportunities and fields to increase understanding of toroidal fusion plasmas.