Cultured murine thyroid epithelial cells expressing transgenic Fas-associated death domain-like interleukin-1beta converting enzyme inhibitory protein are protected from fas-mediated apoptosis.
The antiapoptotic molecule Fas-associated death domain-like IL-1beta-converting enzyme inhibitory protein (FLIP) inhibits Fas-mediated apoptosis by blocking activation of caspase-8. We previously showed that expression of transgenic FLIP on thyroid epithelial cells (TECs) of DBA/1 and CBA/J mice promoted earlier resolution of granulomatous experimental autoimmune thyroiditis in vivo. This study was undertaken to directly determine whether transgenic FLIP expressed on cultured TECs can protect TECs from Fas-mediated apoptosis in vitro. The results indicate that cultured TECs from DBA/1 and CBA/J mice can be sensitized in vitro by interferon-gamma and TNF-alpha to undergo Fas-mediated apoptosis. Transgenic overexpression of FLIP protected cultured TECs of FLIP transgene (Tg)+ DBA/1 and CBA/J mice from Fas-mediated apoptosis, and FLIP small interfering RNA transfection of cultured TECs of FLIP Tg+ DBA/1 and CBA/J mice abolished the protective effect. These in vitro results are consistent with our previous in vivo studies using DBA/1 and CBA/J FLIP Tg+ mice and provide direct support for the hypothesis that transgenic expression of FLIP promotes resolution of granulomatous experimental autoimmune thyroiditis by protecting TECs from apoptosis.
Fang
Yujiang
Y
Division of Immunology and Rheumatology, Department of Medicine, University of Missouri, NE307 Medical Sciences, Columbia, MO 65212, USA. fangy@health.missouri.edu
Braley-Mullen
Helen
H
D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D053446:CASP8 and FADD-Like Apoptosis Regulating Protein / Q000235:genetics / Q000502:physiology*; D053148:Caspase 3 / Q000378:metabolism; D053181:Caspase 8 / Q000378:metabolism; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D053222:Fas Ligand Protein / Q000378:metabolism; D007150:Immunohistochemistry; D007371:Interferon-gamma / Q000494:pharmacology; D051379:Mice; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D008822:Mice, Transgenic; D018613:Microscopy, Confocal; D034741:RNA, Small Interfering / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013961:Thyroid Gland / Q000166:cytology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D019014:fas Receptor / Q000378:metabolism / Q000502:physiology*
D053446:CASP8 and FADD-Like Apoptosis Regulating Protein; D053222:Fas Ligand Protein; C491899:Fas protein, mouse; D034741:RNA, Small Interfering; D014409:Tumor Necrosis Factor-alpha; D019014:fas Receptor; D007371:Interferon-gamma; D053148:Caspase 3; D053181:Caspase 8