Abstract 1261: A mesodissection system for accurate, rapid, and economical recovery of tissue from slide mounted tissue sections

We have developed a prototype system for slide mounted tissue dissection capable of resolution between manual methods (i.e. scraping tissue off of microscope slides) and laser capture microdissection (LCM); here we test the performance of this system. The mesodissection instrument employs a specialized milling tip that simultaneously dispenses and aspirates liquid in order to capture tissue fragments displaced from the slide surface. The accompanying software is capable of transferring electronically indicated target regions between neighboring tissue sections to guide the dissection process. Resolution and accuracy of the system were accessed by microscopic inspection of the dissected region; resolution is the smallest recoverable area and accuracy is the difference between the actual dissected region and the desired region. Purity is defined as the percentage of desired tissue retrieved from a FFPE tissue block made from a human tumor xenografted into mouse, and accessed using real-time PCR amplification of species-specific repetitive DNA elements, as well as unique genomic regions. Efficiency is defined as total DNA recovered relative to manual methods, as quantified by PicoGreen fluorescence. Currently, the system is capable of 0.3 mm resolution and accuracy better than 0.1 mm compared to a desired boundary. Purity is greater than 90% at 0.1mm from the mouse-human tissue boundary. Efficiency is comparable to manual methods when virtually all tissue is recovered from the region of interest. Improvements to the current prototype are ongoing with the goal of less than 0.1 mm resolution. The mesodissection system provides an inexpensive alternative to the limited resolution of manual dissection methods and the high cost and low recovery efficiency of LCM. Digitally targeted dissection using tissue sections derived from adjacent portions of a tissue block allow for determination of a region of interest from a slide optimized for visualization and recovery from a slide optimized for dissection. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1261. doi:1538-7445.AM2012-1261