Abstract
The use of high throughput genetic and expression platforms are generating many candidate diagnostic markers and therapeutic targets for a wide variety of clinical conditions. Tissue microarrays can be used for the evaluation of the utility of many of these markers. However, tissue microarrays can suffer from the limitations associated with sampling and sectioning tissues. We introduce a novel microarray technique based on cell suspensions. Multiple slides can be made, all of which are equally representative of the initial sample. A robotic device was designed that can deposit 60 distinct spots of cytological material on a glass slide. Each spot of cells deposited in this manner may correspond to a unique source. Controlling the number of cells per spot, their distribution within the spot and the size of the spot can be achieved by modifying the viscosity of the cell solution or regulating the amount of fluid deposited. A fully automated analysis of quantitatively stained microarray samples has been performed to quantify the number of cells per spot, the size of spots and the DNA amount per cell in each spot. The reproducibility of these parameters was found to be high.