The flow cytometer is a versatile tool with enormous potential for the study of cells and particles. Because of its unique analytic capabilities, the flow cytometer has become an integral part of the medical research laboratory during the past two decades. The ingress of the flow cytometer into the clinical laboratory has been slower and more controversial. Immunophenotypic analysis and lymphocyte subset analysis is widely performed in the clinical laboratory, but most of the other applications are limited to larger and/or specialized laboratories due to economic considerations. However, no other laboratory instrument provides multiparametric analysis at the single cell level, and the flow cytometer or application-variants of the flow cytometer will become more valuable as medical diagnosis and therapy changes. New fluorochromes, including UV-excited, complex of dyes (“tandem dyes”), and nanocrystals are under development, as well as a new 12generation of modular flow cytometers using small, solid state lasers, robotics, and advanced, innovative bioinformatics software.An example of the new, specialized flow cytometers of the future is the High Throughput Pharmacological System (HTPS).This system, designed for automated high throughput analysis of novel bioresponsemodifying drugs, permits analysis of 9-10 cell samples/minute from 96-well microplates. Another interesting offshoot of the flow cytometer is the laser scanning cytometer (LSC), a microscope slide-based technology capable of acquiring multiparametric data from selected cells from a heterogeneous population which is proving particularly useful for the analysis of fine needle aspirate and body fluid specimens.(15.)
