Turning teratocarcinoma cells into neurons: rapid differentiation of NT-2 cells in floating spheres

Lafage

et al. 2005

J Virol

316

267

To study the capacity of human neurons to mount innate immunity responses to viral infections, we infected cells of a human postmitotic neuron-derivative cell line, NT2-N, with rabies virus (RABV) and herpes simplex type 1 (HSV-1). Changes in neuronal gene expression were analyzed by use of Affymetrix microarrays. Applying a twofold cutoff, RABV increased the transcription of 228 genes, and HSV-1 increased the transcription of 263 genes. The most striking difference between the two infections concerns genes involved in immunity. These genes represent 24% of the RABV-upregulated genes and only 4.9% of the HSV-1-upregulated genes. Following RABV infection, the most upregulated genes belong to the immunity cluster and included almost exclusively genes for beta interferon (IFN-␤) primary and secondary responses as well as genes for chemokines (CCL-5, CXCL-10) and inflammatory cytokines (interleukin 6 [IL-6], tumor necrosis factor alpha, interleukin 1 alpha). In contrast, HSV-1 infection did not increase IFN-␤ gene transcripts and triggered the production of only IL-6 and interferon regulatory factor 1 mRNAs. The microarray results were confirmed by real-time PCR, immunocytochemistry, and enzyme-linked immunosorbent assay. Human neurons were found to express Toll-like receptor 3. They produced IFN-␤ after treatment with poly(I:C) but not with lipopolysaccharide. Thus, human neurons can mount an innate immunity response to double-stranded RNA. These observations firmly establish that human neurons, in absence of glia, have the intrinsic machinery to sense virus infection.

Section: Methodsmentioning

confidence: 99%

Virus Infection Switches TLR-3-Positive Human Neurons To Become Strong Producers of Beta Interferon

Préhaud

Lafage

et al. 2005

J Virol

316

267

“…Human JEG-3 choriocarcinoma (ATCC HTB 36) cells were maintained as previously described (44). Human NT2-N cells (55) were obtained from Ntera-2clD/1 cells (ATCC CRL-1973), which were allowed to differentiate as previously described (10,51). Mixed cultures of human neurons and astrocytes were obtained from Ntera-2D1 cells, according to a specific differentiation protocol (63).…”

Section: Methodsmentioning

confidence: 99%

Modulation of HLA-G Expression in Human Neural Cells after Neurotropic Viral Infections

Lafon

Préhaud

et al. 2005

J Virol

116

“…Human NT2-N neurons (32) and mixed cultures neurons/astrocytes, NT2-N/A (33) were differentiated from Ntera-2clD/1 cells as described (34,35). Purity of the NT2-N and mixed composition of NT2-N/A were checked by RT-PCR as described (36).…”

Section: B7-h1mentioning

confidence: 99%

Detrimental Contribution of the Immuno-Inhibitor B7-H1 to Rabies Virus Encephalitis

Lafon

The Journal of Immunology

Meuth

et al. 2008

108

Rabies virus is the etiological agent of an acute encephalitis, which in absence of post exposure treatment is fatal in almost all cases. Virus lethality rests on its ability to evade the immune response. In this study, we analyzed the role of the immuno-inhibitory molecule B7-H1 in this virus strategy. We showed that in the brain and spinal cord of mice, rabies virus infection resulted in significant up-regulation of B7-H1 expression, which is specifically expressed in infected neurons. Correlatively, clinical rabies in B7-H1−/− mice is markedly less severe than in wild-type mice. B7-H1−/− mice display resistance to rabies. Virus invasion is reduced and the level of migratory CD8 T cells increases into the nervous system, while CD4/CD8 ratio remains unchanged in the periphery. In vivo, neuronal B7-H1 expression is critically depending on TLR3 signaling and IFN-β, because TLR3−/− mice—in which IFN-β production is reduced—showed only a limited increase of B7-H1 transcripts after infection. These data provide evidence that neurons can express the B7-H1 molecule after viral stress or exposure to a particular cytokine environment. They show that the B7-H1/PD-1 pathway can be exploited locally and in an organ specific manner—here the nervous system—by a neurotropic virus to promote successful host invasion.