Flow cytometer – Applications in immunophenotyping
Flow cytometry is used in investigation of whole cells and cellular components such as organelles, nuclei, DNA, RNA, chromosomes, cytokines, hormones, calcium flux, protein content, cell proliferation, and cell cycle. In biomedical area, it is used in cell-cycle analysis, gene expression, vaccine analysis, phagocytosis, immunophenotyping of blood cells, rapid and quantitative measurement of apoptotic cells, cell viability, alteration in the plasma membrane, DNA fragmentation from permeabilized cells, and intracellular cytokine detection besides monitoring the progression of hematological diseases such as leukemia and AIDS. It is also used to assess the reaction of basophils to allergens for the detection of allergic response in the skin test. Moreover, polychromatic flow cytometry is used in preclinical tumor immunology and in cancer immunotherapy such as Ag binding, expression of activation and inhibitory markers, cytokine production, cytotoxicity, and proliferation. Cytokine flow cytometry is used to quantify the percentage of antigen-specific T-cells and determine their phenotypic characteristics, for assessing the activity of natural killer cells, monocytes, and dendritic cells. Flow cytometry with T and B cell markers is employed to enumerate depleting T and B lymphocytes and detection of HLA alloantibody after solid-organ transplantation. Similarly, Raman flow cytometer directly probes intracellular molecules and large heterogeneous populations of single live cells in a label-free manner, and is free from cellular toxicity, photobleaching, interference with biological functions, and nonspecific binding. Further, in vivo flow cytometry allows non-invasive real-time monitoring and detection of circulating tumor cells. Recently, smartphone detectors with built-in and compact cameras have created new possibilities for inexpensive point-of-care diagnostics and healthcare delivery that enables on-site, rapid, reproducible, accurate, inexpensive, and sensitive imaging and sensing of biologically relevant targets of interest.
