Fas expression on human fetal astrocytes without susceptibility to fas-mediated cytotoxicity

doi:10.1016/S0306-4522(97)00455-7

Neuroscience

Volume 84, Issue 2, 11 February 1998, Pages 627-634

https://doi.org/10.1016/S0306-4522(97)00455-7 Get rights and content

Abstract

Fas (APO-1/CD95) is a cell surface receptor, initially identified in lymphoid cells, but more recently detected in the central nervous system under pathologic conditions. Ligation of the fas receptor by fas ligand or by agonist antibodies induces apoptotic cell death in most fas-expressing cells. In the current study, using dissociated cultures of human fetal central nervous system-derived cells, we detected fas expression on astrocytes but not on neurons. Such expression differs from our previous results using cultures of human adult central nervous system-derived cells, which demonstrated fas expression on oligodendrocytes but not on astrocytes; the oligodendrocytes were susceptible to cell death via this pathway. Using multiple assays of cell death, including nuclear propidium iodide and TUNEL staining to detect nuclear-directed injury, cytofluorometric propidium iodide inclusion, and lactate dehydrogenase release to detect membrane-directed injury, we found that fas ligation, however, did not induce cell death in the cultured fetal astrocytes. Cytokines that augmented (γ-interferon) or inhibited (interleukin-4) fetal astrocyte proliferation did not alter fas expression or resistance to fas ligation. Cells obtained immediately ex vivo from human fetal but not from adult central nervous system tissue expressed fas; such expression was restricted to astrocytes as assessed by dual-stain immunohistochemistry. The fetal central nervous system cells did not express fas ligand.

Our findings indicate that fas expression on central nervous system cells may reflect their state of maturity; expression may not, however, always be coupled to susceptibility to cell death via this pathway.

Section snippets

Establishment of human central nervous system-derived glia and neuron cultures

Fetal CNS tissue (cerebral hemispheres) was obtained at 12–16 weeks gestation, following Medical Research Council of Canada approved guidelines. As previously described,[5]the cultures were prepared by dissociation of the fetal CNS tissue with 0.05% trypsin and 50 μg/ml DNaseI and passing the tissue through different meshes. After washing with phosphate-buffered saline, the cells, consisting primarily of neurons and astrocytes, were suspended in modified Eagle's medium supplemented with 5% fetal

Expression of fas on cultured human fetal central nervous system cells

Amongst enriched dissociated cultures of either astrocytes or neurons derived from human fetal CNS tissue, fas immunoreactivity was detected only on astrocytes, as assessed by double-immunofluorescence microscopy and flow cytometry (Fig. 1A–F); such expression was similar to that on the known fas-expressing U251 glioma cell line (Fig. 1G–I). In contrast, fas immunoreactivity was not detected on astrocytes derived from human adult CNS tissue (Fig. 1J,K). Cytokines that augmented (γ-IFN) or

Discussion

The current study demonstrates the following: (i) amongst cultured human fetal CNS-derived cells comprising neurons and astrocytes, expression of fas is restricted to astrocytes, (ii) although fetal astrocytes express fas, they are resistant to cell death induced by fas ligation, (iii) cytokines that augment (γ-IFN) or inhibit (IL-4) fetal astrocyte proliferation do not alter fas expression or resistance of fetal astrocytes to fas ligation, (iv) fas is expressed on immediately ex vivo cells

Acknowledgements

Burkhard Becher has a Fellowship from the German Academic Exchange Service (DAAD/HSPII).

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¹: These authors contributed equally to this work.

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Fas expression on human fetal astrocytes without susceptibility to fas-mediated cytotoxicity

Abstract

Section snippets

Establishment of human central nervous system-derived glia and neuron cultures

Expression of fas on cultured human fetal central nervous system cells

Discussion

Acknowledgements

Fedn. Eur. biochem. Socs Lett.

Cell

Cell

Cell

Blood

J. biol. Chem.

Brain Res.

Brain Res.

Int. J. Immunopharmac.

Cancer Lett.

Curr. Biol.

Cell

Cell

The T cell activation antigen CD27 is a member of the nerve growth factor/tumor necrosis factor receptor gene family

J. Immun.

Fas/APO-1 (CD95) receptor lacking the intracytoplasmic signalling domain protects tumor cells from fas-mediated apoptosis

J. Immun.

Involvement of the CD95 (APO-1/Fas) receptor/ligand system in multiple sclerosis brain

J. exp. Med.

Differential susceptibility of human CNS-derived cell populations to TNF-dependent and independent immune-mediated injury

J. Neurosci.