The proto-oncogene tyrosine kinase receptor encoded by the W locus (CD-117) has been confirmed to be critical to the processes of germ cell proliferation, migration and survival in the rodent. The purpose of the present study was to examine the expression of germ cell-specific CD-117 marker in testis and germ line stem cells (GSCs). The aim of this study was analysis of CD-117 expression as germ cell marker in the seminiferous tubule of mice.

In this experimental study, we employed a comprehensive array of techniques to scrutinize the expression of CD-117. Our analysis encompassed the utilization of immunocytochemistry, immunohistochemistry, Fluidigm real-time Reverse Transcription Polymerase Chain Reaction (RT-PCR), and flow cytometry methodologies.

The Immuno-history-fluorescent analysis revealed the distribution of the germ cell marker CD-117 in the differentiated compartment of seminiferous tubules. High-magnification of confocal microscopy analysis showed surface expression of CD-117 in testis section. Whereas isolated GSCs colonies clearly express the germ-specific protein CD-117, TSCs (testicular stromal cells) were negative for this marker. Fluidigm real-time RT-PCR result demonstrated a significant expression (P < 0.001) of CD-117 in the neonate and adult GSCs compared to TSCs cells. Similarly, flow cytometry analysis confirmed expression of CD-117 in the GSCs colonies and testis cells.

These results discriminate in spite of stage-specific ectopic, expression of CD-117 is a specific germ cell marker for proliferation and differentiation of GSCs into sperm, and can be beneficial for understanding of the signalling pathways related to differentiation of GSCs.