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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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Induction of MHC class I heavy chain, β2-microglobulin  and TAP1/TAP2 gene transcripts in individual neurons by IFN-γ. (A)  Neurons pretreated with IFN-γ (100 U/ml) for 72 h. Gene transcripts for  MHC class I heavy chain, β2-microglobulin (β2-m) and GAPDH coamplified in multiplex from individual neurons (lanes 1–10). Gene transcripts for TAP1 and TAP2 coamplified in parallel from the same neuron  derived samples. Lanes N and M show negative control of PCR-amplification and molecular weight marker ΦX174/Hae III, respectively.  Neurons pretreated with IFN-γ plus TTX for 72 h. Lane arrangement  like in A.
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Figure 6: Induction of MHC class I heavy chain, β2-microglobulin and TAP1/TAP2 gene transcripts in individual neurons by IFN-γ. (A) Neurons pretreated with IFN-γ (100 U/ml) for 72 h. Gene transcripts for MHC class I heavy chain, β2-microglobulin (β2-m) and GAPDH coamplified in multiplex from individual neurons (lanes 1–10). Gene transcripts for TAP1 and TAP2 coamplified in parallel from the same neuron derived samples. Lanes N and M show negative control of PCR-amplification and molecular weight marker ΦX174/Hae III, respectively. Neurons pretreated with IFN-γ plus TTX for 72 h. Lane arrangement like in A.

Mentions: We examined the effect of IFN-γ on the expression of MHC class I–related genes by exposing neuronal cultures for 24 to 72 h to 100 U/ml IFN-γ. This treatment did not cause profound changes. Comparable to untreated cultures, IFN-γ treatment for 24 h resulted in the transcription of MHC class I heavy chain mRNA in 13/20 neurons, while β2-microglobulin transcripts were detected in 7/20 neurons and TAP1 and TAP2 transcripts in 5 out of 20 neurons respectively (Fig. 6 A, Table 2). Remarkably, only 3 out of 20 neurons transcribed all four genes at the same time. The proportion of class I gene transcribing neurons remained essentially stable throughout a IFN-γ treatment period of 72 h.


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)

Induction of MHC class I heavy chain, β2-microglobulin  and TAP1/TAP2 gene transcripts in individual neurons by IFN-γ. (A)  Neurons pretreated with IFN-γ (100 U/ml) for 72 h. Gene transcripts for  MHC class I heavy chain, β2-microglobulin (β2-m) and GAPDH coamplified in multiplex from individual neurons (lanes 1–10). Gene transcripts for TAP1 and TAP2 coamplified in parallel from the same neuron  derived samples. Lanes N and M show negative control of PCR-amplification and molecular weight marker ΦX174/Hae III, respectively.  Neurons pretreated with IFN-γ plus TTX for 72 h. Lane arrangement  like in A.
© Copyright Policy
Related In: Results  -  Collection

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

Figure 6: Induction of MHC class I heavy chain, β2-microglobulin and TAP1/TAP2 gene transcripts in individual neurons by IFN-γ. (A) Neurons pretreated with IFN-γ (100 U/ml) for 72 h. Gene transcripts for MHC class I heavy chain, β2-microglobulin (β2-m) and GAPDH coamplified in multiplex from individual neurons (lanes 1–10). Gene transcripts for TAP1 and TAP2 coamplified in parallel from the same neuron derived samples. Lanes N and M show negative control of PCR-amplification and molecular weight marker ΦX174/Hae III, respectively. Neurons pretreated with IFN-γ plus TTX for 72 h. Lane arrangement like in A.
Mentions: We examined the effect of IFN-γ on the expression of MHC class I–related genes by exposing neuronal cultures for 24 to 72 h to 100 U/ml IFN-γ. This treatment did not cause profound changes. Comparable to untreated cultures, IFN-γ treatment for 24 h resulted in the transcription of MHC class I heavy chain mRNA in 13/20 neurons, while β2-microglobulin transcripts were detected in 7/20 neurons and TAP1 and TAP2 transcripts in 5 out of 20 neurons respectively (Fig. 6 A, Table 2). Remarkably, only 3 out of 20 neurons transcribed all four genes at the same time. The proportion of class I gene transcribing neurons remained essentially stable throughout a IFN-γ treatment period of 72 h.

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