The Principles of Clinical Cytogenetics - Extra Materials - Springer

Automation in the Cytogenetics Laboratory 113
INTRODUCTION
Instrumentation in the Cytogenetics Laboratory
Steven L. Gersen, PhD and Lotte Downey
Ask anyone to envision a typical clinical laboratory, and a host of blinking, whirring, computercontrolled
machines that analyze samples and spit out results usually comes to mind. Even traditionally
labor-intensive settings, such as the cytology laboratory are frequently populated by automatic
stainers, and machines that prepare and automatically analyze pap smears are becoming ever more
popular.
This image does not hold up when one takes a closer look at the modern cytogenetics laboratory.
Although certain procedures have been automated in recent years, most processes are still performed
manually. One message that the reader should take away from this chapter, therefore, is that although
technology can be utilized in any setting, the world of cytogenetics is still essentially one of manual
manipulation and diagnosis.
Nevertheless, no description of the steps involved in producing a cytogenetic diagnosis would be
complete without mention of the instrumentation that has been developed to assist the chromosome
laboratory. Such instrumentation can help with both sample preparation and chromosome analysis
and falls into several basic categories: robotic harvesters, environmentally controlled drying chambers,
and computerized imaging systems, which can also include automation of certain microscopy
steps. There have also been devices developed to eliminate some of the manual steps involved in
performing fluorescence in situ hybridization (FISH) analysis. It should be pointed out that some
cytogenetics laboratories use all of these devices, most use one or two, and some do not use any.
ROBOTIC HARVESTERS
As described in Chapter 4, harvesting of mitotic cells for cytogenetic analysis involves exposing
the cells to a series of reagents that separate the chromosomes, fix them, and prepare them for the
banding and staining process. This traditionally involves pelleting the cells by centrifugation between
steps, in order to aspirate one reagent and add another, a process that, by its very nature, is not
amenable to any form of automation. However, the in situ method of culture and harvest of amniotic
fluid (and other) specimens requires that the cells remain undisturbed in the vessel in which they
were cultured. Therefore, reagents are removed and added without the need to collect the cells in a
tube that can be centrifuged. If the culture vessel is a Petri dish with a removable cover or a similar
type of “chamber slide,” the harvest process does lend itself to automation.
Webster defines a robot as “. . . an automatic apparatus or device that performs functions ordinarily
ascribed to human beings. . . .” In this context, those functions are aspiration of the growth
medium from the culture dish, addition of a hypotonic solution, and, after an appropriate incubation
time, removal of the hypotonic solution and addition of several changes of fixative, each with its own
duration. What is required, then, is a device that can both aspirate and dispense liquids, monitor the
From: The Principles of Clinical Cytogenetics, Second Edition
Edited by: S. L. Gersen and M. B. Keagle © Humana Press Inc., Totowa, NJ
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