Abstract
Spermatogonial stem cells (SSCs) and undifferentiated progenitor spermatogonia in mammalian seminiferous tubules are organized in chains, connected by intracellular bridges. Clone size is generally related to stem cell potential, with shorter chains containing the majority of the stem cell population. Immunofluorescence detection of spermatogonia-specific proteins in whole-mount seminiferous tubule preparations is the only method that allows researchers to relate clone size with the molecular phenotype in spermatogenic lineage development. Here we describe in detail the method used to detect nuclear, cytoplasmic, and cell surface molecules in seminiferous tubules isolated from mouse, monkey, and human testes.