Expression of a functional Fas death receptor by human foetal motoneurons.
The expression of the apoptosis inducer Fas (CD95/APO-1) surface receptor by human foetal neurons was investigated in vitro and ex vivo. Immunofluorescence studies of brain and spinal cord cells in primary cultures and of cryosections obtained from 9- and 10-week-old human foetuses, respectively, showed that all Fas-expressing cells were motoneurons (5.3 and 4.2% of the neurons in brain or spinal cord cultures, respectively) on the basis of morphology, reactivity with the monoclonal antibody SMI-32, a mostly motoneuronal marker and acetylcholine esterase expression. Fas was undetectable on the other cell types in culture. The ability of Fas to induce apoptosis of cultured cells from both tissues was determined by using the terminal transferase (TdT)-mediated dUTP nick-end labelling (TUNEL) method combined with the same double-staining procedure. Under basal culture conditions, about 9% of cells, all glial fibrillary acidic protein-expressing astrocytes, were apoptotic. After a 48-h incubation with Fas ligand, mean 28.5% of brain motoneurons and 29.4% of spinal motoneurons underwent apoptosis, with an inhibition by Z-IETD-FMK, a caspase-8 inhibitor. Hence, Fas appears to be functional through a caspase-8-dependent pathway in a subpopulation of human foetal motoneurons.
Lautrette
C
C
Laboratory of Immunology, CNRS UMR 6101, University Hospital, 2 Avenue Martin Luther King, 87042 Limoges, France.
Giraud
S
S
Vermot-Desroches
C
C
Preud'homme
J L
JL
Jauberteau
M O
MO
D037881:Aborted Fetus / Q000502:physiology; D000110:Acetylcholinesterase / Q000378:metabolism; D017209:Apoptosis; D001253:Astrocytes / Q000378:metabolism; D015153:Blotting, Western / Q000379:methods; D001921:Brain / Q000166:cytology / Q000378:metabolism; D053446:CASP8 and FADD-Like Apoptosis Regulating Protein; D002352:Carrier Proteins / Q000494:pharmacology; D002478:Cells, Cultured; D004347:Drug Interactions; D053222:Fas Ligand Protein; D005455:Fluorescent Antibody Technique / Q000379:methods; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006801:Humans; D020287:In Situ Nick-End Labeling / Q000379:methods; D066298:In Vitro Techniques; D047908:Intracellular Signaling Peptides and Proteins; D019169:Jurkat Cells / Q000187:drug effects / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000494:pharmacology; D009046:Motor Neurons / Q000187:drug effects / Q000378:metabolism*; D016900:Neurofilament Proteins / Q000378:metabolism; D013116:Spinal Cord / Q000166:cytology / Q000378:metabolism; D013997:Time Factors; D019014:fas Receptor / Q000378:metabolism*
D053446:CASP8 and FADD-Like Apoptosis Regulating Protein; C506386:CFLAR protein, human; D002352:Carrier Proteins; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D005904:Glial Fibrillary Acidic Protein; D047908:Intracellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins; D016900:Neurofilament Proteins; D019014:fas Receptor; D000110:Acetylcholinesterase