Multiparametric Flow Cytometry Analysis of Naïve, Memory, and Effector T-Cells.

Polychromatic flow cytometry enables the detection and characterization of markers that are helpful in defining the phenotype of various cell subsets. Here, we described a flow cytometry-based method to characterize the phenotype of naïve, memory, and effector T cells. Being able to differentiate these cells is crucial in understanding immune response and immune profiling. Naïve T cells enable the body to fight off new, unrecognized infections and diseases, and Memory T cells are enriched for response to recall antigens. Furthermore, the antigen-experienced T-cell populations can be broadly divided into effector and memory cell compartments, which are needed to sustain a responsive immune system. Simplistically, the effector T cells require active antigenic stimulation to eliminate pathogens. On the other hand, Memory T cells are described as cells that remain present without antigenic stimulation and can expand rapidly upon secondary challenges. Recently, with the identification of central and effector memory T-cell subsets, tremendous effort has been devoted to characterize markers on the surfaces of these cells. Though various markers have been used to identify the subsets, no single marker that segregates one subset from the other has been described. Thus, multiple markers are needed to subset the cells in order to characterize them. Here we report the verification of a nine-color panel (CD3, CD4, CD8, CD45RO, CD28, CD95, CCR7, Live/Dead Aqua, Dump channel-CD19, CD14, CD56, CD16) that can successfully identify six distinct CD4 and CD8 T-cell populations within the naïve and effector cell subsets from human donors.