Expression patterns and functions of toll-like receptors in mouse sertoli cells.
Toll-like receptors (TLRs) play crucial roles in mediating innate and adaptive immunity. Sertoli cells create a microenvironment that protects seminiferous tubules from autoantigens and invading pathogens. Here we examined the expression and potential function of TLR family in mouse Sertoli cells. RT-PCR, Western blotting, and flow cytometry were used to analyze gene expression. Immunofluorescence staining was used to determine activation of nuclear factor-kappaB. ELISA was used to detect secreted cytokines in culture medium. The phagocytosis assay was performed by Oil Red O staining for lipid droplets. We demonstrated that TLR2, TLR3, TLR4, and TLR5 are highly expressed; TLR6, TLR7, and TLR13 are expressed at relatively low level; and TLR1, TLR8, TLR9, TLR11, and TLR12 are not detected in mouse Sertoli cells. We focused our study on the roles of TLR2-TLR5 in Sertoli cells. Our data indicated that TLR2-TLR5 can be activated by their ligands in mouse Sertoli cells and subsequently increase expression of the inflammatory cytokines IL-1alpha, IL-6, and interferon-alpha, and -beta. The augmented expression of the cytokines might be induced by activation of nuclear factor-kappaB. Notably, activation of TLR3 by its ligand, poly (I:C), specifically promoted phagocytosis of apoptotic spermatogenic cells by Sertoli cells. The TLR-induced Sertoli cell phagocytosis was found to be associated with the up-regulation of scavenger receptors. The results suggest that TLRs expressed in mouse Sertoli cells may play roles in defense against invasion of allo- and autoantigens in the seminiferous tubules.
Wu
Hui
H
Department of Cell Biology, School of Basic Medicine, Peking Union Medical College, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Beijing 100005, People's Republic of China.
Wang
Haikun
H
Xiong
Weipeng
W
Chen
Song
S
Tang
Hongmei
H
Han
Daishu
D
D000818:Animals; D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism; D020869:Gene Expression Profiling; D018836:Inflammation Mediators / Q000378:metabolism; D008024:Ligands; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D016328:NF-kappa B / Q000378:metabolism; D010587:Phagocytosis / Q000235:genetics; D012708:Sertoli Cells / Q000378:metabolism*; D051193:Toll-Like Receptors / Q000819:agonists / Q000235:genetics* / Q000378:metabolism
D016207:Cytokines; D018836:Inflammation Mediators; D008024:Ligands; D016328:NF-kappa B; D051193:Toll-Like Receptors