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Major histocompatibility complex (MHC) class I gene expression in single neurons of the central nervous system: differential regulation by interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha.

Neumann H, Schmidt H, Cavalié A, Jenne D, Wekerle H - J. Exp. Med. (1997)

Bottom Line: The effect of tetrodotoxin is at least partly reverted by the neurotransmitter glutamate.In contrast to IFN-gamma, treatment with TNF-alpha did neither upregulate TAP1/TAP2 nor beta2-microglobulin gene expression, but induced MHC class I heavy chain gene transcription in all neurons.Consequently, no MHC class I molecules were detectable on the membranes of TNF-alpha-treated neurons.

View Article: PubMed Central - PubMed

Affiliation: Department of Neuroimmunology, Max-Planck-Institute for Psychiatry, Martinsried, Germany.

ABSTRACT
This study examined the effect of the pro-inflammatory cytokines interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) on the induction of MHC class I-related genes in functionally mature brain neurons derived from cultures of dissociated rat hippocampal tissue. Patch clamp electrophysiology combined with single cell RT-PCR demonstrated that approximately 50% of the untreated neurons contained mRNA for MHC class I heavy chains, while, with few exceptions, the cells failed to transcribe beta2-microglobulin and TAP1/TAP2 gene transcripts. No constitutive expression of MHC class I protein was detectable by confocal laser microscopy on the surface of neurons. All neurons transcribed the alpha-chain of the interferon-type II receptor (binding IFN-gamma) along with the p55 receptor for TNF-alpha. Sustained exposure to IFN-gamma resulted in transcription of beta2-microglobulin and TAP1/TAP2 genes and MHC class I surface expression in a minor part of the neurons, but did not alter their electrophysiological activities as assessed by whole cell electrophysiology. Suppression of neuronal electric activity by the sodium channel blocker tetrodotoxin drastically increased to almost 100% IFN-gamma-mediated induction of MHC class I chains, of both TAP transporters, and of membrane expression of MHC class I protein. The effect of tetrodotoxin is at least partly reverted by the neurotransmitter glutamate. In contrast to IFN-gamma, treatment with TNF-alpha did neither upregulate TAP1/TAP2 nor beta2-microglobulin gene expression, but induced MHC class I heavy chain gene transcription in all neurons. Consequently, no MHC class I molecules were detectable on the membranes of TNF-alpha-treated neurons.

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Gene transcripts for calnexin, IFN-γ-receptor α-chain and  TNF-α-receptor p55 amplified from individual neurons. Hippocampal  neurons (lanes 1–6) expressing gene transcripts for calnexin (A), for IFNγ-receptor α-chain (B) and for TNF-α-receptor p55 (C). Lanes N and M  show negative control of PCR-amplification and molecular weight  marker X174/Hae III, respectively.
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Figure 4: Gene transcripts for calnexin, IFN-γ-receptor α-chain and TNF-α-receptor p55 amplified from individual neurons. Hippocampal neurons (lanes 1–6) expressing gene transcripts for calnexin (A), for IFNγ-receptor α-chain (B) and for TNF-α-receptor p55 (C). Lanes N and M show negative control of PCR-amplification and molecular weight marker X174/Hae III, respectively.

Mentions: Single cell RT-PCR was performed to examine the transcription of MHC class I heavy chain, β2-microglobulin, TAP1/TAP2 and calnexin genes in individual neurons in the absence of exogenous cytokines or modulatory agents. Transcripts of the MHC class I heavy chain binding protein calnexin gene were present in all analyzed hippocampal neurons (Fig. 4 A), while 12 out of 22 analyzed neurons contained MHC class I heavy chain mRNA (Fig. 3, Tables 1 and 2). In contrast, mRNA for β2-microglobulin was rarely detectable (2 of 22 cells) and TAP1/TAP2 transcripts were absent in all (0/22) analyzed neurons. In contrast, the same single cell RT-PCR technique, when applied to activated T-lymphocytes, detected MHC class I, β2-microglobulin and TAP1/TAP2 mRNA in all cells (Fig. 3, Table 1). In astrocytes we persistently amplified MHC class I heavy chain and β2-microglobulin genes, although TAP1 and TAP2 gene transcripts were detectable only in some, but not all astroglial cells (6/10 and 5/10, respectively).


Major histocompatibility complex (MHC) class I gene expression in single neurons of the central nervous system: differential regulation by interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha.

Neumann H, Schmidt H, Cavalié A, Jenne D, Wekerle H - J. Exp. Med. (1997)

Gene transcripts for calnexin, IFN-γ-receptor α-chain and  TNF-α-receptor p55 amplified from individual neurons. Hippocampal  neurons (lanes 1–6) expressing gene transcripts for calnexin (A), for IFNγ-receptor α-chain (B) and for TNF-α-receptor p55 (C). Lanes N and M  show negative control of PCR-amplification and molecular weight  marker X174/Hae III, respectively.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2196130&req=5

Figure 4: Gene transcripts for calnexin, IFN-γ-receptor α-chain and TNF-α-receptor p55 amplified from individual neurons. Hippocampal neurons (lanes 1–6) expressing gene transcripts for calnexin (A), for IFNγ-receptor α-chain (B) and for TNF-α-receptor p55 (C). Lanes N and M show negative control of PCR-amplification and molecular weight marker X174/Hae III, respectively.
Mentions: Single cell RT-PCR was performed to examine the transcription of MHC class I heavy chain, β2-microglobulin, TAP1/TAP2 and calnexin genes in individual neurons in the absence of exogenous cytokines or modulatory agents. Transcripts of the MHC class I heavy chain binding protein calnexin gene were present in all analyzed hippocampal neurons (Fig. 4 A), while 12 out of 22 analyzed neurons contained MHC class I heavy chain mRNA (Fig. 3, Tables 1 and 2). In contrast, mRNA for β2-microglobulin was rarely detectable (2 of 22 cells) and TAP1/TAP2 transcripts were absent in all (0/22) analyzed neurons. In contrast, the same single cell RT-PCR technique, when applied to activated T-lymphocytes, detected MHC class I, β2-microglobulin and TAP1/TAP2 mRNA in all cells (Fig. 3, Table 1). In astrocytes we persistently amplified MHC class I heavy chain and β2-microglobulin genes, although TAP1 and TAP2 gene transcripts were detectable only in some, but not all astroglial cells (6/10 and 5/10, respectively).

Bottom Line: The effect of tetrodotoxin is at least partly reverted by the neurotransmitter glutamate.In contrast to IFN-gamma, treatment with TNF-alpha did neither upregulate TAP1/TAP2 nor beta2-microglobulin gene expression, but induced MHC class I heavy chain gene transcription in all neurons.Consequently, no MHC class I molecules were detectable on the membranes of TNF-alpha-treated neurons.

View Article: PubMed Central - PubMed

Affiliation: Department of Neuroimmunology, Max-Planck-Institute for Psychiatry, Martinsried, Germany.

ABSTRACT
This study examined the effect of the pro-inflammatory cytokines interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) on the induction of MHC class I-related genes in functionally mature brain neurons derived from cultures of dissociated rat hippocampal tissue. Patch clamp electrophysiology combined with single cell RT-PCR demonstrated that approximately 50% of the untreated neurons contained mRNA for MHC class I heavy chains, while, with few exceptions, the cells failed to transcribe beta2-microglobulin and TAP1/TAP2 gene transcripts. No constitutive expression of MHC class I protein was detectable by confocal laser microscopy on the surface of neurons. All neurons transcribed the alpha-chain of the interferon-type II receptor (binding IFN-gamma) along with the p55 receptor for TNF-alpha. Sustained exposure to IFN-gamma resulted in transcription of beta2-microglobulin and TAP1/TAP2 genes and MHC class I surface expression in a minor part of the neurons, but did not alter their electrophysiological activities as assessed by whole cell electrophysiology. Suppression of neuronal electric activity by the sodium channel blocker tetrodotoxin drastically increased to almost 100% IFN-gamma-mediated induction of MHC class I chains, of both TAP transporters, and of membrane expression of MHC class I protein. The effect of tetrodotoxin is at least partly reverted by the neurotransmitter glutamate. In contrast to IFN-gamma, treatment with TNF-alpha did neither upregulate TAP1/TAP2 nor beta2-microglobulin gene expression, but induced MHC class I heavy chain gene transcription in all neurons. Consequently, no MHC class I molecules were detectable on the membranes of TNF-alpha-treated neurons.

Show MeSH
Related in: MedlinePlus