adoptive-immunotherapy-inkt-cells-glucose-6-phosphate-isomerase-g6pi

Adoptive Immunotherapy of iNKT Cells in Glucose-6-Phosphate Isomerase (G6PI)-Induced RA Mice

Rheumatoid arthritis (RA) is a complex chronic inflammatory autoimmune disease. The pathogenesis of the disease is related to invariant natural killer T ...

Medical School of Hebei University

Key Laboratory of Pathogenesis Mechanism and Control of Inflammatory-Autoimmune Diseases in Hebei Province

The ability of asymmetrical flow field-flow fractionation (AF4) coupled online with multiangle light scattering (MALS) and refractive index detector (RI) (AF4-MALS-RI) for monitoring of change in molecular conformation of wheat and barley starch during germination process was evaluated. AF4 provides separation of starch molecules based on their hydrodynamic sizes, and MALS yields the molar mass and molecular size (radius of gyration, Rg). In vitro and in vivo anti-hyperglycemic effect of germinated wheat and barley was studied. The relationship between antidiabetic activity and molecular conformation was, for the first time, investigated. The ratio of Rg to the hydrodynamic radius (Rh) and the apparent density were proven to be important parameters as they offer an insight into molecular conformation. Results showed that, when geminated, the apparent density and the antidiabetic activity of barley were significantly increased, suggesting germination makes the molecules more compact which could contribute to enhancement of their antidiabetic activity. The information obtained by AF4-MALS-RI is valuable for understanding of germination mechanism, and thus for developing functional foods.

Study on antidiabetic activity of wheat and barley starch using asymmetrical flow field-flow fractionation coupled with multiangle light scattering.

Asymmetrical flow field-flow fractionation (AF4) has been considered to be a useful tool for simultaneous separation and characterization of polydisperse macromolecules or colloidal nanoparticles. AF4 analysis requires the knowledge of the channel thickness (w), which is usually measured by injecting a standard with known diffusion coefficient (D) or hydrodynamic diameter (dh). An accurate w determination is a challenge due to its uncertainties arising from the membrane's compressibility, which may vary with experimental condition. In the present study, influence of factors including the size and type of the standard on the measurement of w was systematically investigated. The results revealed that steric effect and the particles-membrane interaction by van der Waals or electrostatic force may result in an error in w measurement. 

Factors affecting measurement of channel thickness in asymmetrical flow field-flow fractionation.

In this study, asymmetrical flow field-flow fractionation (AF4) coupled online with UV, multiangle light scattering (MALS), and fluorescence (FS) detectors (AF4-UV-MALS-FS) was employed for separation and characterization of egg yolk plasma. AF4 provided separation of three major components of the egg yolk plasma i.e. soluble proteins, low density lipoproteins (LDL) and their aggregates, based on their respective hydrodynamic sizes. Identification of LDL was confirmed by staining the sample with a fluorescent dye, Nile Red. The effect of carrier liquids on aggregation of LDL was investigated. Collected fractions of soluble proteins were characterized using sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). Moreover, the effect of heat and enzymatic treatment on egg yolk plasma was investigated. The results suggest that enzymatic treatment with phospholipase A2 (PLA2) significantly enhances the heat stability of LDL. The results show that AF4-UV-MALS-FS is a powerful tool for the fractionation and characterization of egg yolk plasma components. 

Study on aggregation behavior of low density lipoprotein in hen egg yolk plasma by asymmetrical flow field-flow fractionation coupled with multiple detectors.

In this study, sedimentation field-flow fractionation (SdFFF) was, for the first time, applied for determination of size distribution of Hβ zeolite particles modified by citric acid (CA-Hβ). Effects of the particle dispersion and the carrier liquid composition (type of dispersing reagent (surfactant) and salt added in the carrier liquid, ionic strength, and pH) on SdFFF elution behavior of CA-Hβ zeolite particles were systematically investigated. Also the SdFFF separation efficiency of the particles was discussed in terms of the forces such as van der Waals, hydrophobic, and induced-dipole interactions. Results reveal that the type of salt and pH of the carrier liquid significantly affect the SdFFF separation efficiency of the zeolite particles. It was found that addition of a salt (NaN3) into the carrier liquid affects the characteristic of the SdFFF channel surface. It was found that the use of an acidic medium (pH 3.2) leads to a particle-channel interaction, while the use of a basic medium (pH 10.6) promotes an inter-particle hydrophobic interaction. Result from SdFFF was compared with those from scanning electron microscopy (SEM) and dynamic light scattering (DLS). It seems that, once the experimental conditions are optimized, SdFFF becomes a valuable tool for size characterization of the zeolite particles. 

Sedimentation field-flow fractionation for characterization of citric acid-modified Hβ zeolite particles: Effect of particle dispersion and carrier composition.

The capability of asymmetrical flow field-flow fractionation (AF4) coupled with UV/VIS, multiangle light scattering (MALS) and quasi-elastic light scattering (QELS) (AF4-UV-MALS-QELS) for separation and characterization of egg yolk plasma was evaluated. The accuracy of hydrodynamic radius (Rh) obtained from QELS and AF4 theory (using both simplified and full expression of AF4 retention equations) was discussed. The conformation of low density lipoprotein (LDL) and its aggregates in egg yolk plasma was discussed based on the ratio of radius of gyration (Rg) to Rh together with the results from bio-transmission electron microscopy (Bio-TEM). The results indicate that the full retention equation is more relevant than simplified version for the Rh determination at high cross flow rate. The Rh from online QELS is reliable only at a specific range of sample concentration. The effect of programmed cross flow rate (linear and exponential decay) on the analysis of egg yolk plasma was also investigated. It was found that the use of an exponentially decaying cross flow rate not only reduces the AF4 analysis time of the egg yolk plasma, but also provides better resolution than the use of either a constant or linearly decaying cross flow rate. A combination of an exponentially decaying cross flow AF4-UV-MALS-QELS and the utilization of full retention equation was proved to be a useful method for the separation and characterization of egg yolk plasma. 

Asymmetrical flow field-flow fractionation coupled with multiple detections: A complementary approach in the characterization of egg yolk plasma.

In this work, the ability of asymmetrical flow field-flow fractionation (AF4) coupled with UV-vis, multiangle light scattering (MALS), and quasi-elastic light scattering (QELS) (AF4-UV-MALS-QELS) for monitoring aggregation of components of egg yolk plasma was evaluated. The effect of external factors (i.e., pH, storage conditions, freezing and heat treatments) on the egg yolk plasma was studied. The results reveal that the aggregation mechanism of components of egg yolk plasma during heat and freezing treatment is different. The results suggest that the low density lipoproteins (LDLs) in egg yolk plasma undergo a 'clusters-fusion-gel' process under heat treatment at pH10. The alkaline conditions promote the formation of LDL aggregates. Also, storage conditions play a role in the formation of LDL aggregates. It was found that the hen eggs stored for 7days at room temperature contain less aggregate than those stored at 4°C for the same period. The combination of AF4 with online MALS-QELS provided conformational information in terms of the shape and size distribution of LDL aggregates. AF4-UV-MALS-QELS was proved to be a rapid and gentle method for the separation and characterization of egg yolk plasma aggregates.

Study on external factors affecting egg yolk plasma by asymmetrical flow field-flow fractionation.

In this study, the capacity of asymmetrical flow field-flow fractionation (AF4) coupled with multiangle light scattering (MALS) and differential refractive index (dRI) detectors, to monitor starch retrogradation behavior in situ was evaluated. Meanwhile, the starch samples were characterized by differential scanning calorimetry (DSC) and fourier transform infrared spectroscopy (FTIR). The effect of the botanical origin, amylose/amylopectin ratio, storage conditions (i.e., temperature and time), and salt on starch retrogradation was systematically investigated. The starch aggregation and disassociation is a kinetic equilibrium process that is dependent on the storage conditions and the content of amylose. Moreover, it was found that nitrate ions retarded starch retrogradation behavior by inhibiting the formation of hydrogen bonds between amylose molecules. The results suggest that the formation of the small amylose aggregates plays an important role in starch retrogradation and maize amylopectin degradation. The information obtained by AF4-MALS-dRI is valuable for understanding the starch retrogradation mechanism.

Study on the retrogradation behavior of starch by asymmetrical flow field-flow fractionation coupled with multiple detectors.

The therapeutic effect of adoptive infusion of specific thymus-derived invariant natural killer T (iNKT) cells in a mouse model of rheumatoid arthritis (RA) was observed, and the mechanism of cellular immunotherapy was preliminarily explored.

Haiyang Dou

Medical School of Hebei University

Adoptive Immunotherapy of iNKT Cells in Glucose-6-Phosphate Isomerase (G6PI)-Induced RA Mice