Categories

MIGRATEST® (24 analyses)

Price(USD):$872.04

       *Ask Promo Code:    
Equl SKU Product Name UOM Price(USD) Add to Cart:
10-0800 MIGRATEST® (24 analyses) 24 analyses $872.04  
Introduction:

Quantitative determination of the chemotactic function of neutrophilic granulocytes

Simple and sensitive method for the flow cytometric quantification of the chemotactic function of neutrophilic granulocytes.

24 analyses for 12 patients. Test kit contains multiwell plates plates and precoated cell culture inserts for chemotaxis studies, the chemotactic peptide N-formyl-Met-Leu-Phe (fMLP), an antibody reagent, counting beads and necessary reagents. Evaluation by flow cytometry.

SUMMARY and EXPLANATION

This test allows the quantitative flow cytometric determination of the chemotactic function of neutrophilic granulocytes. In analogy to the Boyden chamber technique, this kit contains multiwell plates and precoated cell culture inserts for chemotaxis studies, the chemotactic peptide N-formyl-Met-Leu-Phe (fMLP), an antibody reagent, counting beads and necessary reagents. It allows determination of the number of neutrophils which have migrated through cell culture inserts towards a concentration gradient of the chemoattractant fMLP.

Also, the decrease of expresssion of the cell adhesion molecule LECAM-1 can be analysed together with the shape-change of the cells by analysing the changes of the forward scatter signals.

 

APPLICATIONS

By MIGRATEST® it is intended to investigate the altered chemotactic function of neutrophils found in various disorders and to evaluate the effects of drugs on this process.

Abnormal chemotaxis was observed and described with a variety of clinical disorders (3, 4). These defects are usually accompanied by recurrent infections of the skin or respiratory tract. Clinical syndromes with frequent infections are already observed in the infant. A functional chemotaxis defect diminishes the number of granulocytes which migrate from the circulation into inflamed tissues and therefore the amount of active cells at the sites of inflammation.

Known inborn defects are Leukocyte Adhesion Deficiency (5), Hyperimmunoglobulin E or Job?s syndrome and Chédiak-Higashi syndrome (CHS). These disorders are associated with a reduced chemotactic activity of neutrophilic granulocytes (6, 7).

Acquired defects can be observed in renal failure, diabetes, hepatic cirrhosis (8) and Hodgkin?s disease. Circulating immune complexes in rheumatoid arthritis also inhibit chemotaxis (10).

Various drugs and immunomodulators can enhance or decrease the chemotactic activity of granulocytes. These effects can be investigated in vitro or ex vivo by application of MIGRATEST®.

 

TEST PRINCIPLES

The phagocytic process can be separated into several major stages: Chemotaxis as the initiating step of phagocytosis (migration of phagocytes to inflammatory sites towards a gradient of chemotactic factors), attachment of particles to the cell surface of phagocytes, ingestion (phagocytosis) and intracellular killing by oxygen-dependent and oxygen-independent mechanisms (1, 2). Phagocytosis by polymorphonuclear neutrophils and monocytes therefore constitutes an essential arm of host defense against bacterial or fungal infections.

MIGRATEST® allows the quantitative determination of neutrophil chemotaxis. The number of cells can be determined which have migrated through cell culture inserts with a pore size of 3.0 µm towards a concentration gradient of the chemoattractant fMLP. In parallel, the decrease of LECAM-1 (11) expression can be measured. Downregulation of this cell adhesion molecule correlates directly with the activation of neutrophils by exposing to chemotactic factors. The shape-change of the cells precedes the cell migration and can be measured by analysing the changes of the forward scatter signals using flow cytometry. The test kit contains the chemoattractant fMLP, cell culture inserts and necessary reagents. Leukocytes are isolated from heparinzed whole blood by spontaneous sedimenation over leukocyte SEPARATION MEDIUM and placed into cell culture inserts. Chemotaxis is conducted at 37°C towards a gradient of fMLP in comparison to a control of INCUBATION BUFFER. The cells are then stained with an antibody reagent (STAINING/COUNTING REAGENT) which also contains counting beads. Just prior flow cytometric analysis a special vital DNA dye is added.

In summary, chemotaxis is the initiating step of the multistep and multifactorial process of phagocytosis (1, 2). The whole cascade of events can be investigated individually under controlled conditions by separate assays: MIGRATEST® to measure chemotaxis, PHAGOTEST® to measure ingestion of bacteria, BURSTTEST (PHAGOBURST®) to measure oxidative burst.

PDF DOWNLOAD