Simple, inexpensive method for automating tissue microarray production provides enhanced microarray reproducibility

Abstract

Tissue microarrays are a novel technology with the potential to impact cancer research by reducing the time, materials, and costs related to specimen-based marker validation. The process uses small cores of specimen tissue for molecular studies, maximizing the quantity of specimens that can be analyzed on a single slide and the results that can be obtained from a single antibody study. However, this process can be tedious and requires a significant time commitment for array production, particularly for the hand-produced tissue array blocks. In addition, this process has significant repetitive motions, risking repetitive stress injury for technical personnel. For these reasons, we have sought a simple, inexpensive system for automation of the existing microarray technologies. Using this system, slides containing as many as 400 specimens can be constructed in a simple and reproducible manner. Automation of the tissue microarray apparatus is accomplished by attaching two stepper motors to the micrometers of the apparatus that control array movement, and it has the advantages of standardizing the spacing between each specimen and eliminating repetitive motions by the user. A computer program is used to run the motors, allowing the user to input commands based on the desired moving distance. After assimilation of the motors, motor control boards, and corresponding program, the final product was tested and demonstrated to provide consistent, reproducible operation. Tissue microarrays were generated with specimen tissue diameters of 1.5 mm, 1.0 mm, and 0.6 mm with core densities upwards of 300 samples per slide.