Open AccessReduction of CTLL‐2 cytotoxicity by induction of apoptosis with a Fas‐estrogen receptor chimera
Author(s) -
Kametaka Minako,
Kume Akihiro,
Okada Takashi,
Mizukami Hiroaki,
Hanazono Yutaka,
Ozawa Keiya
Publication year - 2003
Publication title -
cancer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.035
H-Index - 141
eISSN - 1349-7006
pISSN - 1347-9032
DOI - 10.1111/j.1349-7006.2003.tb01496.x
Subject(s) - ctl* , cytotoxic t cell , estrogen receptor , cytotoxicity , cancer research , fas ligand , apoptosis , biology , perforin , estrogen , immunology , transfection , leukemia , fas receptor , programmed cell death , immune system , cell culture , cd8 , endocrinology , biochemistry , cancer , in vitro , breast cancer , genetics
Allogeneic bone marrow transplantation and donor lymphocyte infusion are powerful treatments for chemotherapy‐resistant leukemia. Tumor eradication is attributed to a graft‐versus‐leukemia reaction by the donor‐derived cytotoxic T lymphocytes (CTLs), but the same cell population may cause severe graft‐versus‐host disease. One strategy to suppress harmful CTL activity is to incorporate a suicide gene into the donor lymphocytes prior to infusion, and to destroy these cells when they aggressively attack nonmalignant host tissues. In this study, we investigated the feasibility of using a Fas‐estrogen receptor fusion protein (MfasER) to control T cell‐mediated cytotoxicity, based on our previous finding that the chimera transmits a Fas‐mediated death signal through activation by estrogen binding. A murine CTL line CTLL‐2 was transfected with a vector encoding MfasER, and the growth, viability and cytotoxic activity of the transfected cells (CTLL/MfasER) were analyzed. The expression of apoptosis‐related proteins such as Fas ligand and perforin was also investigated. In the absence of estrogen, CTLL/MfasER showed similar growth to parental CTLL‐2, and the killing activity was preserved. Addition of 10 −7 M estrogen induced a rapid apoptosis of CTLL/MfasER, and the cytotoxicity was severely impaired. A decrease of Fas ligand and perforin in the estrogen‐treated CTLL/MfasER was seen in an immunoblot analysis. These functional and biochemical analyses showed that the estrogen‐inducible apoptosis in MfasER‐expressing CTLs rapidly terminated their target cell killing. The feasibility of using the MfasER‐estrogen system to control graft‐versus‐host disease was demonstrated.