TY - JOUR
T1 - Prednisone increases apoptosis in in vitro activated human peripheral blood T lymphocytes
AU - Lanza, L.
AU - Scudeletti, M.
AU - Puppo, F.
AU - Bosco, O.
AU - Peirano, L.
AU - Filaci, G.
AU - Fecarotta, E.
AU - Vidali, G.
AU - Indiveri, F.
PY - 1996
Y1 - 1996
N2 - Glucocorticoid hormones (GCH) regulate, through the apoptotic process, the negative selection of immature T cells in the thymus. Because apoptosis seems to occur also in the maintenance of peripheral tolerance, we have investigated whether GCH may induce apoptosis in human mature lymphocytes. Peripheral blood lymphocytes (PBL) or peripheral CD4+ and CD8+ T cell subsets were cultured in the presence of phytohaemaglutinin (PHA) or PHA and prednisone (PDN) at 10-3-10-12 M concentrations for 72, 96 and 120 h. Cell cycle and membrane antigen expression were evaluated by flow cytometry and DNA degradation was detected by agarose gel electrophoresis. PDN blocks PBL growth in the G1 phase of cell cycle and inhibits both IL-2 receptor (IL-2R) expression and IL-2 secretion. Apoptosis is clearly increased by PDN in PHA-activated human PBL, and the apoptotic effect of PDN is stronger on CD8+ than on CD4+ T lymphocytes. All these effects are dose- and time-dependent. The addition of exogenous IL-2 did not rescue lymphocytes from PDN-increased apoptosis. These results show that PDN increases apoptosis in mature activated human peripheral blood lymphocytes, suggesting a possible role of GCH in the maintenance of immune tolerance at post-thymic level.
AB - Glucocorticoid hormones (GCH) regulate, through the apoptotic process, the negative selection of immature T cells in the thymus. Because apoptosis seems to occur also in the maintenance of peripheral tolerance, we have investigated whether GCH may induce apoptosis in human mature lymphocytes. Peripheral blood lymphocytes (PBL) or peripheral CD4+ and CD8+ T cell subsets were cultured in the presence of phytohaemaglutinin (PHA) or PHA and prednisone (PDN) at 10-3-10-12 M concentrations for 72, 96 and 120 h. Cell cycle and membrane antigen expression were evaluated by flow cytometry and DNA degradation was detected by agarose gel electrophoresis. PDN blocks PBL growth in the G1 phase of cell cycle and inhibits both IL-2 receptor (IL-2R) expression and IL-2 secretion. Apoptosis is clearly increased by PDN in PHA-activated human PBL, and the apoptotic effect of PDN is stronger on CD8+ than on CD4+ T lymphocytes. All these effects are dose- and time-dependent. The addition of exogenous IL-2 did not rescue lymphocytes from PDN-increased apoptosis. These results show that PDN increases apoptosis in mature activated human peripheral blood lymphocytes, suggesting a possible role of GCH in the maintenance of immune tolerance at post-thymic level.
KW - Apoptosis T lymphocytes
KW - Cytokines
KW - Glucocorticoids
KW - Prednisone
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M3 - Article
C2 - 8608650
AN - SCOPUS:0029922359
VL - 103
SP - 482
EP - 490
JO - Clinical and Experimental Immunology
JF - Clinical and Experimental Immunology
SN - 0009-9104
IS - 3
ER -