Isolation of THY1+ Undifferentiated Spermatogonia from Mouse Postnatal Testes Using Magnetic-activated Cell Sorting (MACS)

Abstract

In mammals, homeostasis of many tissues rely on a subpopulation of cells, referred to as stem cells, to sustain an appropriate number of undifferentiated and differentiated cells. Spermatogonial stem cells (SSCs) provide the fundamental cellular source for spermatogenesis and are responsible for the lifelong maintenance of the germline pool in testes throughout the reproductive lifespan of males. To gain insight into germline stem cell biology and develop strategies for infertility treatment, several germ cell isolation methods have been reported in order to acquire good quality and quantity of undifferentiated spermatogonia. Among them, magnetic-activated cell sorting (MACS) is an efficient cell isolation method that requires less time and less initial cell numbers to obtain an enriched cell population using an antigen-antibody reaction. Thymus cell antigen 1 (THY1, CD90.2) is recognized as a surface marker of undifferentiated spermatogonia in mouse neonatal and adult testes. Here, we describe a protocol for the isolation of one-week-old THY1+ cells and four-week-old THY1+ cells from mouse testes. The isolation procedure consists of three steps: testis collection and single cell suspension, cell labeling using a biotin-conjugated anti-THY1 antibody and magnetic cell separation. Note, this isolation protocol should be completed within five hours to maximize the quality and the amount of living cells.