Basic Flow Cytometry Instrumentation

Over the last 20 years, flow cytometric analyses have emerged as an integral component of clinical pathology. The clinical applications of flow cytometry range from analysis of T cell subsets in immunodeficiency syndromes, immunophenotyping of hematological malignancies, enumeration of stem cell populations in bone marrow transplantation, DNA content, and cell cycle parameters in a wide range of malignancies to analysis of platelets and enumeration and assessment of maturation of reticulocytes. In AIDS, flow cytometric techniques have become the gold standard for the enumeration of T helper cells [1]. The use of flow cytometry as a tool for the detection of cells positive for a specific HIV DNA or RNA sequence following fluorescence in situ hybridization (FISH), polymerase chain reaction (PCR), or reverse transcriptase polymerase chain reaction (RT-PCR) procedures is becoming a commonly used tool for the investigation of the cellular characteristics of these cells, as well as the cellular heterogeneity within the positive cell population.