BACKGROUND: An understanding of the main mechanism that determines the ability of immune privilege related to Sertoli cells (SC) will provide clues for promoting a local tolerogenic environment. In this report, we established neonatal porcine SC line and evaluated their characteristics. METHODS: SC line was established following the transfection of primary SC (NPSC) from the testis of neonatal pig with plasmid pRNS-1 carrying genes for neomycin resistance and the SV40 large T antigen. Immunohistochemistry and RT-PCR were performed to evaluate the character of immortalized SC lines. RESULTS: Our immortalized SC line (iPS) proliferated stably and had a phenotype similar to NPSC, as indicated by the immunoexpression of follicle stimulating hormone receptor (FSHR), and mRNA expression of androgen receptor (AR), and Wilms' tumor antigen (WT1). Interestingly, NPSC and iPS expressed mRNA of complement regulatory proteins (CRP) such as membrane cofactor protein (CD46), decay accelerating factor (DAF or CD55), and protectin (CD59), but CD59 mRNA expression was negligible in iPS. CONCLUSION: These results suggest that iPS, immortalized by the introduction of SV40 T, retain their original characteristics, except for the relatively low expression of CD59, and that they may be useful for future in vitro and in vivo studies of immune privilege mechanisms related to SC.