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C P Sandiford

Publications and source records attributed to C P Sandiford.

8 recordsLinked to original sources
PubMed1997

Identification of the major water/salt insoluble wheat proteins involved in cereal hypersensitivity.

BACKGROUND: Several studies have investigated water/salt soluble proteins which comprise 50% of the proteins in wheat. The remaining 50% of wheat proteins, are water/salt insoluble proteins of which there is limited information on their role in cereal hypersensitivity. OBJECTIVES: To investigate the allergenicity of the water/salt insoluble gliadin and glutenin proteins (prolamins). METHODS: RAST, electrophoresis and Western blotting were used to identify water/salt insoluble wheat allergens. Competitive RAST inhibition was conducted to investigate cross-reactivity between prolamins and water/salt soluble wheat proteins. RESULTS: Specific IgE to alpha-gliadin and to total glutenins were detected in all sera. IgE to beta-, gamma-, fast omega-, and slow omega-gliadin were present in lower numbers of sera. Prolamin allergens of 90-11 kDa were identified by immunoblotting. Water/salt soluble proteins crossreacted with alpha-gliadin and total glutenins. CONCLUSIONS: Individuals who are hypersensitive to water/salt soluble wheat proteins produce specific IgE to water/salt insoluble wheat proteins. Western blotting has shown that gliadins, glutenins and proteins with similar molecular weights as the endogenous water/salt soluble wheat enzyme inhibitors are important allergens. Alpha and fast omega- are the most allergenic gliadins. The water/salt insoluble proteins share cross-reacting epitopes with water/salt soluble proteins. These data show that the numbers of proteins involved in the development of cereal hypersensitivity is greater than previously believed and that the development of specific IgE to alpha-gliadin may in part depend on the presence of cross-reacting antibodies to water/salt soluble flour allergens.

Antibodies, Blocking↗
PubMed1995

Identification of crossreacting wheat, rye, barley and soya flour allergens using sera from individuals with wheat-induced asthma.

We have conducted radio allergosorbent test (RAST), competitive RAST inhibition, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting using sera from patients with wheat-induced asthma to investigate the immunological relationship between wheat, rye, barley and soya, and to identify common proteins between these flours. RAST showed strong associations between the levels of specific IgE to wheat flour and those of rye and barley flour. Competitive RAST inhibition showed that wheat, rye, barley and soya flours contained crossreacting proteins, in decreasing concentrations. Wheat, rye and barley flours had similar protein profiles on gel electrophoresis. Soya flour contained a number of high molecular weight proteins not present in the other cereals. Western blotting using sera from 21 wheat flour hypersensitive individuals identified a large number of allergens in the different flours. Proteins of 69, 33, 26, 21 and 12 kDa were identified as major wheat flour allergens. Rye flour proteins of 21 and 12 kDa, and barley flour proteins of 69, 52 and 10 kDa were the major allergens identified by serum from wheat hypersensitive individuals. The major common protein of soya and wheat flour had a molecular weight of 21 kDa. The majority of crossreacting allergens identified between the different flours have molecular weights similar to those of known flour enzymes or enzyme inhibitors.

Allergens↗
PubMed1995

Peak exposure concentrations of dust and flour aeroallergen in flour mills and bakeries.

As part of an epidemiological study amongst workers exposed to flour we measured peak exposure levels to total dust and flour aeroallergen with personal samplers in bakeries, flour mills and packing stations. Short-term tasks which were expected to give rise to high concentrations of exposure (peaks) were identified. The frequency and duration of these tasks were estimated and their levels of exposure to dust and flour aeroallergen measured. In total 209 samples were taken. The highest exposure concentrations both for dust (geometric mean > 30 mg m-3) and for flour aeroallergen (geometric mean > 500 micrograms m-3) were measured during certain operations. Exposure concentrations for the tasks were often much higher than the levels we had measured over a shift in a previous study. This might be important for sensitization and for the development of asthma. Peak exposure concentrations could be used to explore the exposure-response relationship more comprehensively. In general average flour aeroallergen concentrations increased linearly with average dust concentrations, although there were some exceptions.

Allergens↗
PubMed1994

Measurement of airborne proteins involved in Bakers' asthma.

We have developed a competitive inhibition immunoassay to measure airborne flour, using purified polyclonal rabbit IgG antibodies to cereal flour antigens. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed different flours contained proteins of molecular weight similar to those present in air sample eluates. Western blotting demonstrated that the purified rabbit IgG antibodies bound to proteins whose molecular weights are similar to human allergens. Air sample eluates obtained from a large bakery had slopes of inhibition parallel to cereal flour when compared in the immuno-inhibition assay. The assay identified airborne proteins from several flours with a detection limit of 1 microgram ml-1. Using this immunoassay we have shown that a wide range of airborne flour concentrations occur in flour mills and a smaller range bakeries. This assay which allows measurement of the concentration of flour aeroallergen in the workplace will be valuable both in epidemiological studies and in examining the effectiveness of interventions to reduce the concentration of flour in the air.

Air Pollutants↗
PubMed1994

The role of cereal and fungal amylases in cereal flour hypersensitivity.

To investigate the role of cereal alpha and beta-amylase in bakers' asthma, we have compared the IgE response of 30 wheat-flour-allergic individuals to barley alpha and beta-amylases with that of fungal alpha-amylase using radioallergosorbent test (RAST), RAST inhibition assays and Western blotting. RAST analysis showed 29 of the 30 subjects with inhalant induced cereal allergy had positive IgE to cereal amylases, but only 16 were positive to fungal alpha-amylase. Regression analysis showed an association between specific IgE to wheat-flour and to barley alpha-amylase (r = 0.70) and barley beta-amylase (r = 0.92) but a poor association with fungal alpha-amylase (r = 0.34). RAST inhibition showed minimal crossreactivity between barley alpha or beta-amylase and barley and fungal alpha-amylase. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting showed that non-reduced barley alpha-amylase had a molecular weight of 54 kDa and barley beta-amylase a molecular weight of 64 kDa. Reduced fungal alpha-amylase had a molecular weight of 54 kDa. Cereal alpha and beta-amylase appear to be important allergens in patients with allergy to flour.

Air Pollutants, Occupational↗
PubMed1994

Determination of the size of airborne flour particles.

Air sampling was done in a UK bakery and a flour mill with an eight-stage cascade impactor to determine the size of airborne flour particles. The concentration of captured material was determined by a competitive inhibition radioimmunoassay. Comparison of the different sites revealed that 8.79% and 52.14% of the particles in the bakery dough-brake and roll-production areas had a diameter < or = 6.0 microns, respectively, and 19.7% of the particles in the flour mill packing area were of this size. We conclude that in dusty areas up to 20% of the airborne flour particles are of a diameter likely to allow them to be deposited in the bronchial airways and alveoli.

Air Pollutants, Occupational↗
PubMed1994

Dust and flour aeroallergen exposure in flour mills and bakeries.

As part of an epidemiological study among workers exposed to flour total dust and flour aeroallergen concentrations were measured with personal samplers over a workshift in three large bakeries and four flour mills and packing stations. In the bakeries geometric means for total dust concentrations ranged from 0.4 mg/m3 in the bread wrapping area up to 6.4 mg/m3 at the dough brake. The flour aeroallergen concentrations ranged from 45.5 micrograms/m3 in the bread wrapping area up to 252.0 micrograms/m3 in the confectionary area. In the flour mills and packing stations the concentrations were higher with geometric means for total dust ranging from 0.5 mg/m3 in the office up to 16.9 mg/m3 for hygiene workers in an old mill. The flour aeroallergen concentrations ranged from 101.5 micrograms/m3 for transport workers up to 1728.2 micrograms/m3 for hygiene workers. The relation between total dust and flour aeroallergen concentrations varied for different areas and depended on the use of products other than flour.

Allergens↗