Gliadin Research Articles

Investigation of seed storage proteins in some wild wheat progenitors using SDS-PAGE and ACID-PAGE.

Wheat storage proteins accounted for up to 60% of the total grain proteins. They form gluten proteins, which make a visco-elastic network enables dough to be processed into bread, pasta and other products. In order to study genetic variation of wild wheat relatives, electrophoretic patterns of seed storage proteins, the high-molecular-weight glutenins and gliadins from about 12 wild species and some check improved cultivars were fractionated by SDS-PAGE and Acid-PAGE. The results showed some close relationship between T. urartu, T. dicoccum and bread wheat in the case of glutenin and gliadin. Therefore It was speculated that progenitor of A genome of cultivated wheat could be T. urartu strongly. A high level of polymorphism was detected in the glutenin and gliadin subunits of the wild wheat relatives, showing some similarities with cultivated bread wheat, useful breeding perspectives. The electrophoresis proved to be a suitable method to discriminate wheat variety and species. Also results of this study confirmed that the genetic variation amongst seed storage proteins of wild relatives were considerable. The wild progenitors are important genetic resources and therefore observed genetic variability could be use in any selection strategies.

HMW-GS variation of somaclones and its variants in Triticum aestivum

Research on somacolonal variation in hexaploid wheat (Triticum aestivum L.) has been conducted a lot and morphological, cytological, and biochemical variations have been observed. Evidence for gene mutations has been obtained through the analysis of gliadin and glutenin in wheat grain, but loci of mutations have not been located. The aims of this study are: firstly, to detect mutation loci of specific gene (Glu-1) to provide exact evi-dence for gene mutation by analyzing changes of high-molecular-weight glutenin subunits

Characterization of gliadin-galactomannan incubation mixtures by analytical ultracentrifugation—Part I. Sedimentation velocity

The aim of this work is to examine the possible interaction and extent thereof of the polysaccharide galactomannan (GAL) with the cereal protein gliadin (GLI) and a peptic-tryptic degraded gliadin (PT-GLI) by analytical ultracentrifugation. The work is part of a series of investigations into the field of coeliac disease (gluten-induced enteropathy) as gliadins are known to be toxic for patients with this disease. The molecular integrity of the GAL and GLI preparations was first checked by sedimentation velocity and sedimentation equilibrium. Sedimentation velocity showed single boundaries indicating homogeneity and low-speed sedimentation equilibrium gave plausible apparent weight average molar masses of 180,000 g/ mol for GAL and 20,000 g/mol for GLI. PT-GLI, GLI and GAL in phosphate buffer (pH 6.5) and the incubated mixtures (stirred for 3 h at 37 °C; PT-GLI: GAL = 3.53:1, wt.wt.; GLI:GAL = 0.23 and 0.55:1, wt.wt.) were then investigated by sedimentation velocity at a temperature of 20 °C. The plots of 1 s 20 vs. c of GAL, PT-GLI-GAL and GLI-GAL mixtures after incubation show a significantly different shape suggesting the presence of interactions. According to the equation 1 s 20 = 1 s o 20 (1 + k sc) , values for { s o 20, k s } of {(4.02 ± (490.9 ± 28.9) ml/ g, {(5.92 ± 0.24) S, (1152 ± 44) ml/g} and {(5.38 ± 0.19) S, (1141 ± 38) ml/g} for GAL and PT-GLI-GAL and GLI-GAL mixtures, respectively, were obtained. The concentration of GAL ranged from 0.75–3.0 mg/ml for GAL alone and from 0.34–1.50 mg/ml in the incubated mixtures. This apparent indication for a weak non-covalent protein-polysaccharide interaction was further supported by UV absorption spectrometry and gel filtration.

Celiac disease and other nutrient related injuries to the gastrointestinal tract.

Celiac disease is the major nutrient-induced disease of the small intestine. The disease is traditionally characterized by villous atrophy responsive to gliadin. Recent data suggest that there is an extended spectrum of gluten sensitivity that includes first-degree relatives and patients with latent celiac disease. Genetic studies have identified HLA DQ A1 *0501 B1 *0201 as the predominant HLA gene most tightly linked to this condition. Gliadin-specific T cell clones restricted by DQ have now been identified in the small intestine lamina propria. Such T cells may be important in mediating many of the features of the disease. This review discusses the interrelationship of genetics, cereal chemistry, environmental factors, and immunology involved in the pathogenesis of celiac disease and explores its relationship with other nutrient-induced enteropathies.

Functional Consequences of the Binding of Gliadin to Cultured Rat Mesangial Cells: Bridging Immunoglobulin A to Cells and Modulation of Eicosanoid Synthesis and Altered Cytokine Production

Oral immunization with gliadin (GLI) can induce immunoglobulin A mesangial deposits (IgA nephropathy [IgAN]) in mice. A role for GLI in human IgAN has been inferred from an association with celiac disease, increased serum anti-GLI IgA in patients with IgAN, and benefit from a gluten-free diet observed in some IgAN patients. These effects might be due to the antigenic or lectinic properties of GLI. The aim of our study was to investigate whether GLI binding to glycosylated residues (ie, lectinic activity) favors binding of GLI to cultured rat mesangial cells, bridging IgA macromolecules. We also sought to determine whether GLI binding alters mesangial cell function. Gliadin binds to rat mesangial cells in the third and fourth passages, as determined by immunofluorescence. Gliadin binding is inhibited by co-incubation with 1 mol/L N-acetyl-D-glucosamine and 1 mol/L alpha-D-mannose, sugars competitive for this lectinic bond. Quantification by biotinylated GLI revealed a significant dose-dependent binding of GLI (P < 0.001) inhibited by N-acetyl-D-glucosamine (P < 0.05). Some saccharolytic enzymes, like invertase, modify the cell surface to decrease GLI binding (P < 0.02). In addition, GLI promoted the binding of purified mouse polymeric IgA to mesangial cells. The binding of GLI to mesangial cells modulates arachidonic acid metabolism by cultured mesangial cells, significantly inhibiting prostaglandin E2 production (P < 0.02), increasing synthesis of thromboxane B2 (P < 0.01) and tumor necrosis factor (P < 0.001), but not interleukin-1 beta. These responses were abrogated by co-incubation with N-acetyl-D-glucosamine and/or pretreatment with invertase. Non-immune binding of an environmental alimentary lectin, GLI, to mesangial cells in culture might favor the binding of IgA and IgAIC to mesangial cells, enhancing both IgA mesangial trapping and in situ IgA deposit formation. This could occur via GLI-specific antibodies or by virtue of the binding of nonspecific IgA on a lectinic basis, or both. Moreover, related changes in eicosanoid synthesis might stimulate mesangial cell growth and mesangial matrix production, together with mesangial cell contraction, contributing to the pathogenesis of IgAN.

Antibodies to dietary antigen in serum from patients with sickle cell anemia.

The levels of antibodies of the IgG, IgA and IgM isotypes reacting against ovoalbumin (OVA), gliadin (GL) and cow's milk proteins (CMP), were determined by ELISA in sera from a group of adult patients with sickle cell anemia (SCA) bearing homozygous Ss hemoglobinopathy and from matched health donors. Only patients with steady-state disease were included in the study. Increased amounts of IgG and IgA reacting with OVA, GL and CMP were observed in the group of patients as compared with the controls. In contrast, the levels of IgM antibodies against each of the three dietary antigens were similar in patients and controls. Increased levels of IgG and IgA antibodies against dietary antigens in SCA may result from enhanced permeability of the gut mucosa to macromolecules of dietary origin as a consequence of microinfarctions, chronic polyclonal B cell activation and/or diminished inhibitory control of antibody synthesis.

IgG Subclasses to Food Proteins in Atopic and Normal Individual

IgG subclass antibodies to ovalbumin (OVA), gliadin (GLI) and beta-lactoglobulin (beta-lac) were determined in 18 atopic subjects and 18 age- and sex-matched controls. IgG antibodies to OVA and GLI were found predominantly as IgG4 subclass, with the IgG antibodies to beta-lac distributed evenly between IgG2, IgG3 and IgG4 in both groups. The proportion of anti-OVA IgG antibodies in the IgG3 subclass was significantly higher in the atopic group (22%) than in the nonatopic group (8%: p < 0.001). The proportion of anti-GLI IgG3 antibodies was also higher in the atopic group (43%) than the nonatopic group (24%: p < 0.001). OVA subclass antibodies in the atopic and nonatopic subjects were mainly IgG4, and GLI subclass antibodies were mainly IgG3 and IgG4. This study provides information on the distribution of IgG subclasses to food proteins, and in particular those related to protein GLI. The importance of IgG3 subclasses in atopic disease is highlighted; this phenomenon, to our knowledge, has not previously been reported.

Review of methods for measuring gliadins in food.

Review of methods for measuring gliadins in food.

340 Immunomodulation of gluten and gliadin induced ADCC by OM-89

340 Immunomodulation of gluten and gliadin induced ADCC by OM-89

Errata

Paper by I. Kemp and E. K. Rideal, “On the Cataphoresis of Gliadin.” 'Proceedings ’ A, vol. 147, p. 1 (November) 1934. p. 9, line 17, for ξ 1 e 1 +ξ 2 e 2 / k T read ξ 1 e 1 + ξ 2 e 2 / k T