FKBP12 is the only FK506 binding protein mediating T-cell inhibition by the immunosuppressant FK506

Xuehong Xu, Bing Su, Robert J. Barndt, Hanying Chen, Hongbo Xin, Guifan Yan, Linyuan Chen, Dongsheng Cheng, Joseph Heitman, Yuan Zhuang, Sidney Fleischer, Weinian Shou

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33 Scopus citations


Background. FK506-binding proteins (FKBP) are immunophilins that interact with the immunosuppressive drugs FK506 and rapamycin. Several FKBP family members such as FKBP12, FKBP12.6, and FKBP51 are expressed in T cells. It has been speculated that these FKBPs are possibly redundant in the immunosuppressant-induced T-cell inactivation. To determine the pharmacological relevance of multiple FKBP members in the immunosuppressant-induced T-cell inactivation, we have investigated the physiological responses of FKBP12-deficient and FKBP12.6-deficient mutant T cells to the immunosuppressive agent FK506. Methods. FKBP12-deficient and FKBP12.6-deficient T cells were isolated from genetically engineered FKBP12-deficient and FKBP12.6-deficient mice, respectively. T-cell growth inhibitory assay was used to assess their responses to immunosuppressant FK506 treatments. Results. We found that growth inhibition induced by FK506 is abolished in FKBP12-deficient cells but not in FKBP12.6-deficient cells. Conclusions. FKBP12 is the only FKBP family member that plays a key role in immunosuppressant-mediated immunosuppression.

Original languageEnglish (US)
Pages (from-to)1835-1838
Number of pages4
Issue number11
StatePublished - Jun 15 2002


ASJC Scopus subject areas

  • Transplantation

Cite this

Xu, X., Su, B., Barndt, R. J., Chen, H., Xin, H., Yan, G., Chen, L., Cheng, D., Heitman, J., Zhuang, Y., Fleischer, S., & Shou, W. (2002). FKBP12 is the only FK506 binding protein mediating T-cell inhibition by the immunosuppressant FK506. Transplantation, 73(11), 1835-1838.