Stage-specific localization and expression of c-kit in the adult human testis.
The c-kit receptor (KIT) and its ligand, stem cell factor (SCF), represent one of the key regulators of testicular formation, development, and function and have been extensively studied in various animal models. The present study was undertaken to characterize the pattern of localization and expression of c-kit in normal adult human testis. Immunohistochemical analysis showed that KIT is expressed in the cytoplasm of spermatogonia, acrosomal granules of spermatids, and Leydig cells. Interestingly, a rather heterogenous pattern of expression of the protein along the basement membrane was observed. Intense protein localization in spermatogonia was detected in stages I-III, whereas low expression was observed in stages IV-VI of the seminiferous epithelium, indicating that the expression of the molecule was stage specific. In situ hybridization studies revealed that the transcripts of the gene were also localized in a similar non-uniform pattern. To the best of our knowledge, such a stage-specific expression of KIT has not been reported previously in the human testis. The results of the present study may expand current knowledge about the c-kit/SCF system in human spermatogenesis.
Scientist D and Divisional Head, Stem Cell Biology Department, National Institute for Research in Reproductive Health (ICMR), J M Street, Parel, Mumbai 400012, India.
Sreepoorna K
SK
Unni
Deepak N
DN
Modi
Shilpa G
SG
Pathak
Jayesh V
JV
Dhabalia
Deepa
D
Bhartiya
D000368:Aged; D001485:Basement Membrane / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007985:Leydig Cells / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D019009:Proto-Oncogene Proteins c-kit / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013091:Spermatogenesis; D013093:Spermatogonia / Q000378:metabolism; D013737:Testis / Q000378:metabolism*
D012333:RNA, Messenger; D019009:Proto-Oncogene Proteins c-kit