Cytopress: Automated slide preparation of cytologic material from suspension

Abstract

This paper describes a new automated system to prepare slides of cytological material from suspension. The system collects material on a filter tape by filtration and transfers it to glass slides by means of pressure-fixation. Using cervical cells as a model, results show that a well-defined cell number is evenly deposited over a standardized area, while a small number of cells is retained on the tape and a negligible number lost in the filtrate. Contamination is very small. Application of the system to other cytological material (fine needle aspirations, monolayer and cell suspension cultures, agar cultures, and isolated nuclei) is shown. In general, more than one slide can be made from one sample. Several histological staining procedures as well as immunofluorescence labeling protocols can be applied to the preparations obtained in this way. This system thus introduces a method that will standardize specimen preparation, is quick, saves operator time, and can be used for both diagnostic and research applications.Key terms: Specimen preparation, cervical cells, fine needle aspirations, cell cultures, tumor cell colonies, isolated nuclei Light microscopical examination of cellular material by human observers has been performed almost exclusively on conventionally prepared and stained slides. Demands on the quality of the preparations were not so extreme because the observer could correct for most preparative shortcomings. To improve this visual and qualitative evaluation, new techniques for cell interpretation are being developed. Our laboratory is involved in this research, developing, among others, specific immunohistochemical stains to detect the tissue origin of tumor cells (18)(19)(20)(21), to detect quantitative morphologic and cytochemical changes using image analysis derived techniques (6,30,31), and to assess the malignant behavior of tumor cells in an in vitro model system (5,8,9,27). These new techniques require the preparation of reproducible, well-standardized specimens with homogeneously dispersed, nonoverlapping, single cells or cell groups. Therefore, to complement this research, the development of new cytopreparatory techniques has begun (12,15,16). One of the steps in this specimen preparation procedure is the deposition of cells from suspension onto glass slides. Numerous approaches have been described to achieve this goal. These approaches can be subdivided into three classes: centrifugation (1,2,10,24-261, sedimentation (7,12,28), and transferring the cells through an intermediate filter onto a slide (2,11,16,17,22,23). In the last procedure, the cells either remain on the filter (2,17) or are transferred to the slide by touch (22,23) or pressure (11,161. In a previous paper (16) we have evaluated the latter method. Cells were collected on a polycarbonate filter membrane and transferred to glass slides by simultaneous pressure-fixation. This procedure proved to be relatively robust with respect to parameters that might influence cell recovery such as filtration rate, filter pore size, and pr...

Evaluation of DNA and nuclear protein features for their use in describing normal and malignant endometrium

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Semiautomated Monolayer Preparation of Bronchial Secretions Using AutoCyte PREP

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Basic Preparative Techniques for Fluorescence In Situ Hybridization

“…In automated analytical cytology, it is well established that cell density and overlap are decisive factors in gaining speed of analysis (Van Driel-Kulker et al, 1980). Preparation techniques derived from this field include bucket centrifugation and unit-gravity sedimentation as well as filter collection and imprint methods (see Oud et al, 1986 for literature entries in this field).…”