[Development of mRNA quantification after fluorescence activated cell sorting].

Recent studies using stem cells or cancer stem cells have revealed the importance of detecting minor populations of cells in blood or tissue and analyzing their biological characteristics. These cells can be separated from other cells by fluorescence-activated cell sorting (FACS) using antibodies that bind to surface antigen; however, the majority of these cells do not have specific surface antigens. Furthermore, the cells must be kept alive throughout the procedure to analyze their biological characteristics. To improve these limitations, we have established a novel laboratory test named mRNA quantification after fluorescence-activated cell sorting(FACS-mQ). Using this method, cells are sorted by a specific gene expression pattern, and the gene expression profile in the sorted cells can be easily analyzed. In this feature, we will introduce the typical applications of FACS-mQ targeting intracellular mRNA and intracellular nuclear antigens. These methods will hopefully contribute to the accumulation of knowledge regarding human stem cells, cancer stem cells, and small populations of cells, the biological characteristics of which are mostly unknown.