title: Flow cytometry analysis of the Fas ligand expression of activated lymph node T-cells.
abstract: There is increasing evidence for the role of the Fas/Fas ligand interaction in the immunoregulation of T-cells. We studied the expression of the Fas ligand (FasL) in activated peripheral T-cell in vitro, and its relation to autonomous cell death by flow cytometry. Following the stimulation of lymph node T-cells with anti-CD3 and rIL2, the mRNA level of FasL increased more than four times during the first 2 days over the level before stimulation. The surface expression of FasL was observed on 27% of the population at day 2 after stimulation and increased to approximately 50% at day 3. Kinetic analysis by flow cytometry, however, indicated that all T-blasts transformed during activation did not express FasL. FasL expression became evident simultaneously with the termination of cell expansion. Since cells remained viable (> 90%) at day 3 as judged by trypan blue-exclusion, cell membranes expressing FasL were supposed to be still intact. Concomitantly with FasL-expression, spontaneous DNA fragmentation was observed. These observations support the idea that autonomous Fas/FasL interaction mediates apoptosis in activated peripheral T-cells as demonstrated in T-cell hybridoma or established T-cells.
authors.affiliation: Department of Microbiology, Fujita Health University School of Medicine, Aichi, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Sasaki
authors.forename: T
authors.initials: T
authors.lastname: Kobayashi
authors.forename: S
authors.initials: S
authors.lastname: Imamura
authors.forename: T
authors.initials: T
authors.lastname: Shigekura
authors.forename: R
authors.initials: R
authors.lastname: Kato
authors.forename: Y
authors.initials: Y
authors.lastname: Kawamoto
authors.forename: T
authors.initials: T
authors.lastname: Tsuji
authors.forename: A
authors.initials: A
authors.lastname: Miyama
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000235:genetics; D002478:Cells, Cultured; D053222:Fas Ligand Protein; D005260:Female; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D007376:Interleukin-2 / Q000494:pharmacology; D008198:Lymph Nodes / Q000166:cytology*; D008213:Lymphocyte Activation / Q000235:genetics; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics; D051379:Mice; D008807:Mice, Inbred BALB C; D016853:Muromonab-CD3 / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000166:cytology / Q000378:metabolism*
chemical_list: D053222:Fas Ligand Protein; C505658:Fasl protein, mouse; D007376:Interleukin-2; D008562:Membrane Glycoproteins; D016853:Muromonab-CD3; D012333:RNA, Messenger; D011994:Recombinant Proteins