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31.
ABEL TRUJILLO-OCAMPO HYUN-WOO CHO AMANDA C. HERRMANN WILFREDO RUIZ-VAZQUEZ ANDREW B. THORNTON HONG HE DAN LI MARIAM A. QAZILBASH QING MA STEVEN A. PORCELLI ELIZABETH J. SHPALL JEFFREY MOLLDREM JIN S. IM 《Cytotherapy》2018,20(8):1089-1101
Background aims
CD1d-restricted invariant natural killer (iNK) T cells are rare regulatory T cells that may contribute to the immune-regulation in allogeneic stem cell transplantation (ASCT). Here, we sought to develop an effective strategy to expand human iNK T cells for use in cell therapy to prevent graft-versus-host disease (GVHD) in ASCT.Methods
Human iNK T cells were first enriched from peripheral blood mononuclear cells (PBMCs) using magnetic-activated cell sorting separation, then co-cultured with dendritic cells in the presence of agonist glycolipids, alpha-galactosylceramide, for 2 weeks.Results
The single antigenic stimulation reliably expanded iNK T cells to an average of 2.8?×?107 per 5?×?108 PBMCs in an average purity of 98.8% in 2 weeks (N?=?24). The expanded iNK T cells contained a significantly higher level of CD4+ and central memory phenotype (CD45RA?CD62L+) compared with freshly isolated iNK T cells, and maintained their ability to produce both Th-1 (interferon [IFN]γ and tumor necrosis factor [TNF]α) and Th-2 type cytokines (interleukin [IL]-4, IL-5 and IL-13) upon antigenic stimulation or stimulation with Phorbol 12-myristate 13-acetate/ionomycin. Interestingly, expanded iNK T cells were highly autoreactive and produced a Th-2 polarized cytokine production profile after being co-cultured with dendritic cells alone without exogenous agonist glycolipid antigen. Lastly, expanded iNK T cells suppressed conventional T-cell proliferation and ameliorated xenograft GVHD (hazard ratio, 0.1266; P < 0.0001).Conclusion
We have demonstrated a feasible approach for obtaining ex vivo expanded, highly enriched human iNK T cells for use in adoptive cell therapy to prevent GVHD in ASCT. 相似文献32.
Effect of self-association on the structural organization of partially folded proteins: inactivated actin 总被引:1,自引:0,他引:1
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IM Kuznetsova AG Biktashev SY Khaitlina KS Vassilenko KK Turoverov VN Uversky 《Biophysical journal》1999,77(5):2788-2800
The propensity to associate or aggregate is one of the characteristic properties of many nonnative proteins. The aggregation of proteins is responsible for a number of human diseases and is a significant problem in biotechnology. Despite this, little is currently known about the effect of self-association on the structural properties and conformational stability of partially folded protein molecules. G-actin is shown to form equilibrium unfolding intermediate in the vicinity of 1.5 M guanidinium chloride (GdmCl). Refolding from the GdmCl unfolded state is terminated at the stage of formation of the same intermediate state. An analogous form, known as inactivated actin, can be obtained by heat treatment, or at moderate urea concentration, or by the release of Ca(2+). In all cases actin forms specific associates comprising partially folded protein molecules. The structural properties and conformational stability of inactivated actin were studied over a wide range of protein concentrations, and it was established that the process of self-association is rather specific. We have also shown that inactivated actin, being denatured, is characterized by a relatively rigid microenvironment of aromatic residues and exhibits a considerable limitation in the internal mobility of tryptophans. This means that specific self-association can play an important structure-forming role for the partially folded protein molecules. 相似文献
33.
The use of dilute acids to catalyze the hydrolysis of hemicellulose to its sugar constituents is well-known and effective. However, a major problem associated with this pretreatment is the poor fermentability of the produced hydrolyzate as a result of the presence of the microorganism's inhibitory compounds. In the present work, seven ion-exchange resins were tested in order to detoxify corn stover hydrolyzate. Regarding xylose recovery, it was observed that more than 92% recovery was feasible. Furfural removal varied from 53.% to 99.%, and hydroxymethylfurfural (HMF) removal was effective between 37% and 100%. Acetic acid was totally removed by Purolite A 103 S resin. Corn stover hydrolyzate (CSH) treated with Purolite A 103 S, and Finex CS 14 GC resins, was tested as substrate for xylitol production using a yeast, Candida mogii. Product yields, Yp/s, of 0.41 and 0.37 g/g and cellular yields, Yx/s, of 0.24 and 0.13 g/g, respectively, were obtained using the two types of resin-treated hydrolyzates. 相似文献
34.
de Carvalho W da Silva SS Vitolo M de Mancilha IM 《Zeitschrift für Naturforschung. C, Journal of biosciences》2000,55(3-4):213-217
In this study we used the yeast Candida guilliermondii FTI 20037 immobilized by entrapment in Ca-alginate beads (2.5-3 mm diameter) for xylitol production from concentrated sugarcane bagasse hemicellulosic hydrolysate in a repeated batch system. The fermentation runs were carried out in 125- and 250-ml Erlenmeyer flasks placed in an orbital shaker at 30 degrees C and 200 rpm during 72 h, keeping constant the proportion between work volume and flask total volume. According to the results, cell viability was substantially high (98%) in all fermentative cycles. The values of parameters xylitol yield and volumetric productivity increased significantly with the reutilization of the immobilized biocatalysts. The highest values of xylitol final concentration (11.05 g/l), yield factor (0.47 g/g) and volumetric productivity (0.22 g/lh) were obtained in 250-ml Erlenmeyer flasks containing 80 ml of medium plus 20 ml of immobilized biocatalysts. The support used in this study (Ca-alginate) presented stability in the experimental conditions used. The results show that the use of immobilized cells is a promising approach for increasing the xylitol production rates. 相似文献
35.
Silva SS Ramos RM Rodrigues DC Mancilha IM 《Zeitschrift für Naturforschung. C, Journal of biosciences》2000,55(1-2):10-15
Xylitol, a sweetener comparable to sucrose, is anticariogenic and can be consumed by diabetics. This sugar has been employed successfully in many foods and pharmaceutical products. The discovery of microorganisms capable of converting xylose present in lignocellulosic biomass into xylitol offers the opportunity of producing this poliol in a simple way. Xylitol production by biotechnological means using sugar cane bagasse is under study in our laboratories, and fermentation parameters have already been established. However, the downstream processing for xylitol recovery is still a bottleneck on which there is only a few data available in the literature. The present study deals with xylitol recovery from fermented sugar cane bagasse hydrolysate using 5.2 g/l of aluminium polychloride associated with activated charcoal. The experiments were performed at pH 9, 50 degrees C for 50 min. The results showed that aluminium polychloride and activated charcoal promoted a 93.5% reduction in phenolic compounds and a 9.7% loss of xylitol from the fermented medium, which became more discoloured, facilitating the xylitol separation. 相似文献
36.
Rachel IM van Haaften Blanche Schroen Ben JA Janssen Arie van Erk Jacques JM Debets Hubert JM Smeets Jos FM Smits Arthur van den Wijngaard Yigal M Pinto Chris TA Evelo 《BMC bioinformatics》2006,7(1):200-15
Background
Gene expression microarray technology permits the analysis of global gene expression profiles. The amount of sample needed limits the use of small excision biopsies and/or needle biopsies from human or animal tissues. Linear amplification techniques have been developed to increase the amount of sample derived cDNA. These amplified samples can be hybridised on microarrays. However, little information is available whether microarrays based on amplified and unamplified material yield comparable results. 相似文献37.
1. Aposematic coloration in prey promotes its survival by conspicuously advertising unpalatability to predators. Although classical examples of aposematic signals involve constant presentation of a signal at a distance, some animals suddenly display warning colours only when they are attacked. 2. Characteristics of body parts suddenly displayed, such as conspicuous coloration or eyespot pattern, may increase the survival of the prey by startling the predator, and/or by signalling unpalatability to the predators at the moment of attack. 3. The adaptive value of such colour patterns suddenly displayed by unpalatable prey has not been studied. We experimentally blackened the red patch in the conspicuous red–white–black hindwing pattern displayed by an unpalatable insect Lycorma delicatula White (Hemiptera: Fulgoridae) in response to predator's attack. 4. There was no evidence that the presence of the red patch increased prey survival over several weeks. We hypothesise that predators generalised from the red–white–black patches on the hindwings of unpalatable L. delicatula to any similar wing display as a signal of unpalatability. Because a higher proportion of males than females stay put at their resting sites, displaying their wings in response to repeated attacks by predators, wing damage was more frequent in males than in females. 5. To our knowledge, this is the first experimental test of an adaptive role of aposematic signals presented by unpalatable prey during sudden displays triggered by direct predatory attack. 相似文献
38.
B B Fuks A I Shapoval I Grzhebin IM 《Biulleten' eksperimental'no? biologii i meditsiny》1991,112(7):78-80
We investigated the phenomenon of increased sensitivity of tumor-bearing mice to endotoxin shock. I/V administration of sera from tumor (EL-4, B16, R815, MOPC-315) bearers or tumoral culture media into intact mice caused the increased sensitivity to lethal action of LPS plus GMDP. Production of TNF in above mice was also significantly increased under the influence of LPS plus GMDP. Sensitivity induced factors in tumor bearing mice sera have mol. weight more than 50 kDa. This action was partially abolished by indomethacin. 相似文献