title: CD59 cross-linking induces secretion of APO2 ligand in overactivated human T cells.
abstract: Jurkat cells and the derived TCR / CD3-defective subline, J.RT3.T3.5 undergo activation induced cell death (AICD) when stimulated with phytohemagglutinin (PHA). Since J.RT3.T3.5 cells do not express antigen receptor, we searched for the molecules that could be ligated by PHA and induce AICD in this cell line. We show here that the glycosylphosphatidylinositol linked CD59 molecule is expressed at the surface of Jurkat and J.RT3.T3.5 cells, and when cross-linked by specific antibodies can induce cell death. The toxicity of supernatants from PHA-stimulated Jurkat or J.RT3.T3.5 cells was prevented by a combination of the blocking anti-Fas mAb SM1 / 23 and anti-APO2L / TRAIL mAb 5C2. However, toxicity of supernatants from anti-CD59 stimulated cells was specifically prevented by the anti-APO2L blocking antibody. Anti-CD59 cross-linking induced AICD also in normal human T cell blasts, which secreted toxic molecules into the supernatant. The toxicity of these supernatants on Jurkat cells was fully prevented by the anti-APO2L blocking antibody, showing that CD59 crosslinking induces the preferential release of APO2L also in normal T cells. The possible physiological and / or pathological consequences of this observation are discussed.
authors.affiliation: Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Monleón
authors.forename: M J
authors.initials: MJ
authors.lastname: Martínez-Lorenzo
authors.forename: A
authors.initials: A
authors.lastname: Anel
authors.forename: P
authors.initials: P
authors.lastname: Lasierra
authors.forename: L
authors.initials: L
authors.lastname: Larrad
authors.forename: A
authors.initials: A
authors.lastname: Piñeiro
authors.forename: J
authors.initials: J
authors.lastname: Naval
authors.forename: M A
authors.initials: MA
authors.lastname: Alava
mesh_terms: D000595:Amino Acid Sequence; D019138:Antibodies, Blocking / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000276:immunology; D017209:Apoptosis / Q000187:drug effects; D051017:Apoptosis Regulatory Proteins; D015415:Biomarkers / Q000032:analysis; D018957:CD59 Antigens / Q000276:immunology / Q000378:metabolism*; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D017077:Culture Media, Conditioned; D053222:Fas Ligand Protein; D006801:Humans; D019169:Jurkat Cells; D008213:Lymphocyte Activation / Q000187:drug effects / Q000276:immunology*; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck) / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000276:immunology / Q000378:metabolism*; D008969:Molecular Sequence Data; D010835:Phytohemagglutinins / Q000494:pharmacology; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051076:Proto-Oncogene Proteins c-fyn; D011940:Receptor Aggregation; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000502:physiology; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism*; D053221:TNF-Related Apoptosis-Inducing Ligand; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology / Q000378:metabolism*; D019014:fas Receptor / Q000276:immunology / Q000378:metabolism
chemical_list: D019138:Antibodies, Blocking; D000911:Antibodies, Monoclonal; D051017:Apoptosis Regulatory Proteins; D015415:Biomarkers; D018957:CD59 Antigens; D017077:Culture Media, Conditioned; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D008562:Membrane Glycoproteins; D010835:Phytohemagglutinins; D011518:Proto-Oncogene Proteins; D011948:Receptors, Antigen, T-Cell; D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha; D019014:fas Receptor; C494957:FYN protein, human; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck); D051076:Proto-Oncogene Proteins c-fyn; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases