实验基础

The correct transport of biological material is one of the major aspects of biolegislation. The awareness of this fact has only quite slowly come into being. The demands on the export, packaging, and shipping of biological material are manifold and the number of possible mistakes is endless. On the ...

Heavy metals are removed by Serratia sp. via the activity of a cell-bound, atypical, PhoN-type acid phosphatase enzyme, which liberates HPO42- from a suitable organic phosphate donor, with the stoichiometric precipitation of heavy-metal cations (M2+) as insoluble MHPO4 at the cell surfa ...

Detection of sulfur compounds is difficult in complex samples such as soil and food. The volatility of these compounds can be an advantage if a trapping method is used. This method must be inert for the highly reactive compounds to avoid artifacts resulting from sample preparation and analysis pr ...

The intestinal microbiota is a postnatally acquired organ that is composed of a large diversity of bacterial genera and species and has an influence on the physiology of the host, both locally at the intestine and systemically. They perform important functions for the host and can, in turn, be modul ...

Allergens are molecules with the capacity to elicit IgE responses in humans. When stimulated with allergens, most allergic patients respond with production of IgE specific for several proteins/allergens in the source material. The standardization of allergen extracts is essenti ...

Many naturally occurring proteins, peptides, carbohydrates, nucleic acids, and lipids, as well as synthetic peptides, are successful immunogens. To elicit an immune response, a compound must contain an antigenic determinant or epitope and must be of sufficient size to initiate lympho ...

Immunoelectrophoresis can be used for analysis of individual proteins in complex mixtures. The conditions involved in immunoelectrophoresis are mild, avoiding the risk of denaturation, and it is possible to perform relative quantification of individual components. The princ ...

Under normal conditions, airborne allergens are present at very low concentrations. Allergens may be carried on relatively large identifiable particles such as grains of pollen and mould spores or smaller amorphous particles or both. The methods that have been applied to quantify anim ...

The Halogen assay is a new technique for measuring airborne allergen. The assay is unique in that it is capable of analyzing allergens and particles together, combining the advantages of morphological approaches and immunoassay. The Halogen assay allows direct observation of the parti ...

After air sampling and elution, the air sample eluate contains an unknown amount of allergens together with other materials. The proteins of interest can be quantified using immunoassays, which are sensitive, economical, and can be used for high throughput. However, the amount of antigen or a ...

There is currently considerable interest in the role of specific IgG antibodies in allergy. Several studies suggest that specific IgG antibodies may play a protective role in allergy. Successful immunotherapy is associated with increases in allergen-specific IgG antibodies whi ...

The prevalence of allergic disease has dramatically increased over the past 30 years in Westernised countries. It is unlikely that the rapid increase in the prevalence of allergic disease is the result of genetic changes, which highlights the importance of environmental factors in the dev ...

Identification of pollen is like entering a world of great variation in size, shape, and structure. To obtain a correct result, a good microscope, basic information on pollen grain morphology and a reference sample of the plant to be identified are needed. Purity determination of pollen can be perf ...

Proper understanding of the pathogenesis of type I allergy relies on the identification of allergen epitopes. The phage display technique is a relatively new one to define peptide structures that mimic natural epitopes, including conformational B-cell epitopes. Peptides display ...

Mast cells generate mediators of inflammation which are stored in granules and secreted on activation either by allergen crosslinking of membrane-bound IgE or through other stimuli. Most methods for mast cell identification rely on the histochemical detection of constituents of the ...

Mast cells are key effector cells of the allergic response. When stimulated by specific allergen through the high-affinity IgE receptors or through other stimuli, these cells release a number of potent mediators of inflammation. Amongst these are the serine proteases tryptase and chyma ...

The activation of mast cells is of pivotal importance in the pathogenesis of allergic conditions. Mast cell activation can provoke rapid increases in microvascular permeability, induce bronchoconstriction after blood flow, stimulate the recruitment and activation of other in ...

Peripheral blood mononuclear cells (PBMC) can be used to assess cell-mediated immunity in general or, via antigen-specific stimulation, to detect previous exposure to a variety of antigens/allergens and to monitor the response to immunotherapies. Peripheral blood is the most common ...

Allergen-specific T-cell lines established from allergic patients provide the opportunity of investigating T-cell functions at the poly- or oligoclonal level. T-cell lines are useful in determining the presence or absence of antigen-specific T-cell reactivity. However, to obta ...

T-cell receptors (TcR) recognize short linear peptides (9–15 amino acid long), which have been processed by an ‘antigen-presenting cell’ and complexed to products of the major histocompatibility complex (MHC). Peptides of the appropriate shape and charge are able to bind within the groove ...