Apoptosis of the allo-antigen specific T cells induced by CD34(+) cells transfected with exogenous gene FasL / 中国实验血液学杂志

ABSTRACT

To investigate the value of apoptosis of the allo-antigen specific T cells induced by Fas/FasL pathway in order to prevent GVHD in allo-transplant, the CD34(+) cells were transfected with FasL or not, used as effector cells, mixed with allo-antigen specific T lymphocytes with presence or absence of IFN-gamma or IL-2. After 5 days, apoptosis of T cells was detected by TdT nick end mediated dUTP labeling (TUNEL) and flow cytometry. The effects of IFN-gamma or IL-2 on apoptosis of CD34(+) cells of graft induced by Fas/FasL pathway observed as controls. The apoptosis incidence of T cells was (12.1 +/- 1.5)% when CD34(+) cells transfected with FasL were used as effector cells, that was much higher than that T cells with CD34(+) cells non-transfected (p < 0.01). In the presence of IFN-gamma or IL-2, apoptosis incidence reached to (20.1 +/- 2.3)% or (17.6 +/- 1.3)% respectively (p < 0.01). When sFasL was added to CD34(+) cells freshly isolated or induced with IFN-gamma or IL-2, the incidence or apoptosis of CD34(+) cells was (7.8 +/- 0.8)%, (18.7 +/- 1.6)% (p < 0.01) or (7.9 +/- 1.0)% (P > 0.05) respectively. The results suggest that it is possible to induce apoptosis of the allo-antigen specific T cells in grafts activated by allo-antigen by exogenous Fas ligand expressed on receptor cells and that may hopefully provide a new method to prevent GVHD