title: Flow cytometry for natural killer T cells: multi-parameter methods for multifunctional cells.
abstract: Valpha24-Jalpha18 invariant natural killer T cells (iNKT) are an evolutionary conserved sub-lineage of T cells with effector-memory phenotype that often express an NK cell surface antigen CD161 and is characterized by reactivity to self-glycolipids and alpha-galactosylceramide (alphaGalCer) that are presented by monomorphic HLA class-I-like molecule CD1d. Upon antigen recognition, iNKT cells can rapidly produce multiple cytokines and chemokines and regulate development of Th-2 and Th-1 immune responses. Potential importance of iNKT cells has been demonstrated in several animal models of infection diseases, autoimmunity, and cancer. Multi-parameter flow cytometry has been the main tool to study human and murine iNKT cells. Analysis of human iNKT cells is particularly demanding since their frequency among peripheral blood T cells is relatively low ranging from less than 0.01% to 1%, with a mean of about 0.1%. Herein, we discuss flow cytometry applications that are utilized for iNKT cell identification and enumeration, subset characterization, detection of intracellular cytokines, quantitative analysis of multiple secreted molecules, cell-mediated cytotoxicity, and migration.
authors.affiliation: Division of Hematology-Oncology, Department of Pediatrics, Children's Hospital Los Angeles and Keck School of Medicine, University of Southern California, Los Angeles, CA 90027, USA. lmetelitsa@chla.usc.edu
authors.forename: Leonid S
authors.initials: LS
authors.lastname: Metelitsa
mesh_terms: D000818:Animals; D002465:Cell Movement / Q000276:immunology; D016207:Cytokines / Q000032:analysis; D003602:Cytotoxicity, Immunologic; D005434:Flow Cytometry / Q000379:methods*; D005455:Fluorescent Antibody Technique; D006801:Humans; D007694:Killer Cells, Natural / Q000166:cytology / Q000276:immunology*; D008213:Lymphocyte Activation / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D016207:Cytokines