Using a quartz crystal microbalance biosensor for the study of metastasis markers on intact cells.

The use of biosensors has become a standard method to characterize biomolecular interactions. Data obtained from biosensor studies are widely used to evaluate drug candidates, particularly in relation to their binding properties towards a selected target. The importance of measuring such interactions in a biologically relevant environment has become the new challenge for the biosensor technologies.

Real-time analysis of the carbohydrates on cell surfaces using a QCM biosensor: a lectin-based approach.

A novel approach to the study of molecular interactions on the surface of mammalian cells using a QCM biosensor was developed. For this study, an epidermoid carcinoma cell line (A-431) and a breast adenocarcinoma cell line (MDA-MB-468) were immobilized onto polystyrene-coated quartz crystals. The binding and dissociation between the lectin Con A and the cells as well as the inhibition of the binding by monosaccharides were monitored in real time and provided an insight into the complex avidic recognition of cell glycoconjugates.

Collagen I and III and their decorin modified surfaces studied by atomic force microscopy and the elucidation of their affinity toward positive apolipoprotein B-100 residue by quartz crystal microbalance.

Collagen, the major component of extracellular matrix (ECM) and the most abundant protein in the human body, is implicated in the development of atherosclerosis. Collagen types I and III were immobilized on fused-silica capillary to investigate their shape, size and structure by atomic force microscopy (AFM). For comparison, collagen was also immobilized on a mica surface.

Quartz crystal microbalance, a valuable tool for elucidation of interactions between apoB-100 peptides and extracellular matrix components.

Atherosclerosis has received wide attention as a primary cause of premature death in developed countries. The retention of low-density lipoprotein (LDL) particles in the intima, the inner layer of the capillaries, has been imputed as the main cause of the development of atherosclerotic plaques. The entrapment of LDL is mainly due to the specific interaction between the lysine-rich site on apolipoprotein B-100 (apoB-100), a major apolipoprotein of LDL, and extracellular matrix (ECM) components such as collagen, proteoglycans, and glycosaminoglycans (GAGs).

Proteome analysis of metastatic colorectal cancer cells recognized by the lectin Helix pomatia agglutinin (HPA).

The lectin from Helix pomatia (HPA) binds to adenocarcinomas with a metastatic phenotype but the glycoconjugates of cancer cells that bind to the lectin have yet to be characterized in detail. We used a model of metastatic (HT29) and nonmetastatic (SW480) human colorectal cancer cells and a proteomic approach to identify HPA binding glycoproteins. Cell membrane proteins purified by HPA affinity chromatography, were separated by 2-DE and analyzed by MS.