Comparison of Classical Lowry, Modified Lowry and a Dye-Binding Assay for the Estimation of Protein in Allergen Extracts and Influence of Different Parameters on the Modified Lowry Assay

We investigated sera of 12 patients with IgE-mediated hypersensitivity reactions to potato, using different in vitro methods. Radioallergosorbent test classes 2–4 (7.6–46.5% binding) were measured with potato allergen disks. Immunoblot detected allergen bands with an isoelectric point range of approximately 4.5–5.2 and mainly in a molecular weight range between 16.00 and 30.00 kD. But also at molecular weights of 43.00 and 65.00 kD allergen bands (IgE specificities) could be detected. Histamine release assay performed with isolated fractions of the potato extract showed a great individual variation and positive results of fractions of molecular weights between 10.00 and 80.00 kD. From our data we conclude that raw potato is a ‘multiallergenic’ vegetable.

Section: Radioallergosorbent Testmentioning

confidence: 99%

IgE-Mediated Allergic Reactions to Potatoes

Wahl¹,

Lau²,

Maasch³

et al. 1990

“…Protein concentrations were determined by a modified Lowry procedure [12,13]. A calibrated solution of human serum albumin (Behringwerke, Marburg, FRG) served as standard.…”

Section: Determination Of Protein and Carbohydratementioning

confidence: 99%

Allergens of Horse Epithelium

Franke¹,

Maasch²,

Wahl³

et al. 1990

We investigated five horse epithelial allergen extracts prepared from different qualities of raw material by several biochemical and immunochemical methods. Horse serum albumin and horse serum were used to identify serum-related antigens. We found high similarities as well as marked differences between the extracts. There were strong differences in the protein contents, the protein patterns obtained by isoelectric focusing and sodium dodecyl sulfate polyacrylamide gel electrophoresis, the total allergenic activities obtained by radioallergosorbent test inhibition assays and the amounts and numbers of serum-related proteins. The patterns of dander-related allergens in crossed radioimmunoelectrophoresis were similar but showed partly strong differences in allergen concentrations. Allergen compositions determined by blotting methods showed only minor differences between the investigated epithelial extracts. It appears that some of the differences, e.g. the content of serum-related proteins, depend on the way the different raw materials are prepared. Because serum-related extract components are not considered as major allergens, their content should be low in horse epithelial allergen extracts. For this reason whole skin cannot be recommended as starting material for horse epithelium allergen extract preparation.

“…Protein concentrations were determined by a modified Lowry procedure [5,6]. A calibrated solution of human serum albumin (Behringwerke, Marburg, FRG) served as standard.…”

Section: Determination O F Protein and Carbohydratementioning

confidence: 99%

Quality of Timothy Pollen <i>(Phleum pratense) </i>from Different Pollen Seasons and Different Suppliers

Maasch¹,

Geißler²,

Winter³

et al. 1986

We investigated seven batches of timothy (Phleum pratense) pollen from four different pollen seasons and three different manufacturers in the USA and Europe by several biochemical and immunochemical methods. By measuring the contents of hexoses, proteins and the total allergenic activity using RAST inhibition we could not find any significant differences in quality between pollen of different seasons, different geographical origin and different manufacturers. There were only slight differences in the staining of some protein bands and in peak height of some antigens in isoelectric focusing (IEF), SDS-PAGE and crossed immunoelectrophoresis. These differences in IEF and SDS-PAGE patterns seem to be specific for the pollen samples from the USA and Europe, respectively. We also observed minor differences in IEF immunoprint patterns, mainly for some basic proteins. The allergen patterns in crossed radioimmunoelectrophoresis were very similar, with only minor differences in concentration of the basic allergens. It appears that timothy pollen from different years can be produced in different geographical areas by different manufacturers with fairly constant allergenic activity.