Processing of Cell-Touch Preparations

Often, depending on the circumstances, it is necessary to obtain information about a lesion immediately, or the need to examine the cells without cutting into them precludes the use of frozen sections. Touch preparations or imprints enable the examination of the whole cell apart from the tissue aspect. The cells are obtained by touching a wet tissue with a glass slide. Cells adhere to the glass in roughly the same orientation as they exist on the surface of the lesion touched. Fixing them in place enables one to examine the cells for a rapid investigation without having to freeze and cut through a tissue block. If cytological information is needed, touch preparations can be obtained easily from the surface of otherwise large tissue fragments. In the event that smears or aspirates cannot be adequately performed or the sample is too small for extra studies, touch preparations can provide a means of quick cell identification or examination (1 ). Cells that are acquired in this manner can provide information about such things as membrane receptors and some cell-adhesion molecules in the absence of the tissue structural components. Sometimes tissue structural elements can interfere with the ability to identify a substance associated with a particular cell. Cell-touch preparations made at the time of specimen removal can then be used. The opinions or assertions herein represent the personal views of the author, and are not to be construed as official or as representing the views of the Department of the Army or the Department of Defense