CHROMOSOME PREPARATIONS FROM SOLID TUMORS OF THE MOUSE: A DIRECT METHOD

Abstract

A technique has been described whereby excellent chromosome preparations can be obtained from solid tumors and certain other somatic tissues of the mouse through the use of the flame drying technique. Tumor bearing mice are pretreated with colchicine and the tissues removed. After hypotonic treatment and simple fixation the tissue is converted to a free cell suspension with the aid of a Swinney adapter. Drops of the cell suspension are then put onto pre-cleaned cold slides and the metaphase plates are spread by igniting the fixative. This affords more control in spreading than does squashing, air drying, or heating over a flame. After flaming, slides are stained with Sudan Black B or with Giemsa, or may be prepared with other standard methods. A high percentage of the cells are well spread without overlaps. Drifting of chromosomes is no problem, and large numbers of completely workable cells are usually found on a single slide. The method has been used successfully with neoplastic tissues which witn other methods yielded consistently poor results.