TNF - Tumor Necrosis Factor

TNF Gene, Tumor Necrosis Factor

Introduction

Tnf Tumor Necrosis Factor is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.

<div class="infobox infobox-gene"> [@swardfager2010]

| Attribute | Value | [@swardfager]
|-----------|-------| [@barnum2014]
| Gene Symbol | TNF | [@komine2018]
| Full Name | Tumor Necrosis Factor |
| Chromosomal Location | 6p21.33 |
| NCBI Gene ID | [7124](https://www.ncbi.nlm.nih.gov/gene/7124) |
| Ensembl ID | ENSG00000232890 |
| UniProt ID | [P01375](https://www.uniprot.org/uniprot/P01375) |
| OMIM | [191160](https://www.omim.org/191160) |
| Gene Family | TNF superfamily |
| Protein Class | Cytokine |

</div>}

Overview

The TNF gene encodes Tumor Necrosis Factor (TNF-α), a potent pro-inflammatory cytokine that plays central roles in immune regulation, inflammation, and cell death. TNF is primarily produced by activated macrophages and [microglia](/cell-types/microglia-neuroinflammation), and has profound effects on neuronal survival and function in the central nervous system.

Molecular Function

Signaling Pathways

TNF signals through two receptors:

• TNFR1 (p55): Ubiquitous, death domain
• TNFR2 (p75): Immune cells, tissue-specific
• [NF-κB](/entities/nf-kb) Activation: Pro-inflammatory genes
• Caspase Activation: [Apoptosis](/entities/apoptosis) pathways

Signaling Pathways

TNF activates multiple downstream pathways upon receptor binding:

...

TNF Gene, Tumor Necrosis Factor

Introduction

Tnf Tumor Necrosis Factor is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.

<div class="infobox infobox-gene"> [@swardfager2010]

| Attribute | Value | [@swardfager]
|-----------|-------| [@barnum2014]
| Gene Symbol | TNF | [@komine2018]
| Full Name | Tumor Necrosis Factor |
| Chromosomal Location | 6p21.33 |
| NCBI Gene ID | [7124](https://www.ncbi.nlm.nih.gov/gene/7124) |
| Ensembl ID | ENSG00000232890 |
| UniProt ID | [P01375](https://www.uniprot.org/uniprot/P01375) |
| OMIM | [191160](https://www.omim.org/191160) |
| Gene Family | TNF superfamily |
| Protein Class | Cytokine |

</div>}

Overview

The TNF gene encodes Tumor Necrosis Factor (TNF-α), a potent pro-inflammatory cytokine that plays central roles in immune regulation, inflammation, and cell death. TNF is primarily produced by activated macrophages and [microglia](/cell-types/microglia-neuroinflammation), and has profound effects on neuronal survival and function in the central nervous system.

Molecular Function

Signaling Pathways

TNF signals through two receptors:

• TNFR1 (p55): Ubiquitous, death domain
• TNFR2 (p75): Immune cells, tissue-specific
• [NF-κB](/entities/nf-kb) Activation: Pro-inflammatory genes
• Caspase Activation: [Apoptosis](/entities/apoptosis) pathways

Signaling Pathways

TNF activates multiple downstream pathways upon receptor binding:

| Pathway | Key Effectors | Cellular Outcome |
|---------|---------------|------------------|
| NF-κB | IKK, IκB, p65/p50 | Pro-inflammatory gene transcription |
| MAPK | JNK, p38, ERK | Stress response, survival |
| Caspase-8 | Death domain signaling | Apoptosis or necroptosis |
| ERK1/2 | MEK1/2, Elk-1 | Cell proliferation, differentiation |

TNFR1 vs TNFR2 Signaling

| Feature | TNFR1 (p55) | TNFR2 (p75) |
|---------|-------------|-------------|
| Expression | Ubiquitous | Immune cells, endothelial |
| Death domain | Present | Absent |
| Primary signaling | NF-κB, apoptosis | NF-κB, survival |
| Function | Pro-inflammatory | Tissue repair,免疫 regulation |

Downstream Effectors

The TNF signaling network includes:

• Transcription factors: NF-κB, AP-1, STAT3
• Kinases: IKK, MAPKs, PI3K/Akt
• Caspases: Initiator and effector caspases
• Adaptor proteins: TRADD, TRAF2, RIP1, FADD

Biological Activities

| Activity | Mechanism |
|----------|-----------|
| Inflammation | Leukocyte recruitment |
| Cytotoxicity | Apoptosis induction |
| Fever | Hypothalamic effect |
| Cachexia | Metabolic effects |

Expression Pattern

Brain

• [Microglia](/entities/microglia): Primary source in CNS
• [Astrocytes](/entities/astrocytes): Inflammatory activation
• [Neurons](/entities/neurons): Expression under stress
• Endothelial Cells: BBB regulation

Disease Associations

Alzheimer's Disease

• Neuroinflammation: Key mediator
• Amyloid Interaction: Synergistic toxicity
• Therapeutic Target: TNF inhibitors
• Genetic Association: TNF polymorphisms

Parkinson's Disease

• Microglial Activation: Chronic neuroinflammation
• Neuronal Death: Contributes to degeneration
• Therapeutic Potential: Anti-TNF strategies

Multiple Sclerosis

• Demyelination: Inflammatory damage
• Therapeutic Target: Etanercept trials
• [Blood-Brain Barrier](/entities/blood-brain-barrier): Permeability effects

Stroke

• Ischemic Injury: Exacerbates damage
• Therapeutic Window: TNF modulation

Therapeutic Implications

Approved Drugs

| Drug | Type | Indication |
|------|------|------------|
| Etanercept | TNF receptor-Fc fusion | RA, psoriasis |
| Infliximab | Anti-TNF antibody | IBD, RA |
| Adalimumab | Anti-TNF antibody | Autoimmune |

CNS Applications

• Blood-Brain Barrier: Challenge for delivery
• Peripheral Targeting: Indirect CNS effects
• Research: PET ligands for TNF imaging

Key Publications

• PMID: 11585629(https://pubmed.ncbi.nlm.nih.gov/11585629/) - TNF in neurodegeneration
• PMID: 14583152(https://pubmed.ncbi.nlm.nih.gov/14583152/) - TNF in Alzheimer's disease

Background

The study of Tnf Tumor Necrosis Factor has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.

Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.

See Also

• [Proteins Index](/proteins)
• [TNF-alpha Protein](/proteins/tnf-alpha-protein)
• [Neuroinflammation](/mechanisms/neuroinflammation-pathway)

External Links

• [NCBI Gene TNF](https://www.ncbi.nlm.nih.gov/gene/7124)
• [UniProt P01375](https://www.uniprot.org/uniprot/P01375)
• [OMIM 191160](https://www.omim.org/191160)

TNF Signaling Pathways

TNF exerts its effects through two distinct receptors:

TNFR1 (p55/p60)

• Expressed ubiquitously in most tissues
• [Activates NF-κB, MAPK, and caspase-8 pathways](/institutions/cas)
• [Mediates both pro-survival and pro-apoptotic signaling](/genes/th)
• [Contains death domain for apoptosis induction](/genes/th)

TNFR2 (p75/p80)

• [Expressed primarily in immune cells and endothelial cells](/cell-types/endothelial-cells)
• [Activates NF-κB and MAPK pathways](/genes/th)
• [Predominantly pro-survival signaling](/genes/gnal)
• [Limited to certain cell types including microglia](/projects/cell-types)

TNF in Neuroinflammation

TNF plays a central role in neuroinflammatory processes:

Microglial Activation

• [TNF released by activated microglia creat](/cell-types/microglia)es a feedback loop
• Promotes release of other cytokines (IL-1β, IL-6)
• Enhances antigen presentation and phagocytosis
• Can shift microglial phenotype between M1 and M2 states

Blood-Brain Barrier Permeability

• TNF increases BBB permeability through endothelial activation
• Promotes leukocyte infiltration into CNS
• Upregulates adhesion molecules (ICAM-1, VCAM-1)
• Therapeutic target for neuroinflammatory conditions

TNF in Specific Neurodegenerative Diseases

Alzheimer's Disease

• Elevated TNF levels in AD brains and CSF
• Aβ oligomers induce TNF production in microglia
• TNF promotes tau phosphorylation and aggregation
• Anti-TNF therapies being investigated

Parkinson's Disease

• Increased TNF in substantia nigra of PD patients
• Dopaminergic neurons show heightened TNF sensitivity
• TNF contributes to neuroinflammation in PD
• TNF blockade may provide neuroprotection

Amyotrophic Lateral Sclerosis (ALS)

• Elevated TNF in ALS patients and mouse models
• Mutant SOD1 astrocytes promote TNF release
• Contributes to motor neuron death
• Anti-TNF strategies in preclinical testing

Multiple Sclerosis

• TNF crucial for demyelination and lesion formation
• TNF-blocking antibodies (infliximab, etanercept) tested
• Paradoxical effects noted in some patients
• TNF still a therapeutic target

Therapeutic Targeting

TNF Inhibitors

| Drug | Type | Status | Notes |
|------|------|--------|-------|
| Etanercept | Fusion protein | Clinical trials | Failed in AD |
| Infliximab | Antibody | Clinical trials | Mixed results |
| Adalimumab | Antibody | Clinical trials | Tested in MS |
| Thalidomide | Small molecule | Preclinical | Anti-TNF activity |

Challenges

• TNF has both beneficial and harmful effects
• Peripheral vs CNS targeting issue
• Blood-brain barrier penetration
• Timing of intervention critical

Animal Models

Transgenic and knockout mouse models have been instrumental:

• TNF knockout mice show reduced neuroinflammation
• TNFR1 knockout protective in some models
• Neuron-specific TNF overexpression causes degeneration
• Astrocyte-specific TNF drives demyelination

Biomarkers

TNF and its receptors serve as biomarkers:

• CSF TNF elevated in AD, PD, MS
• Soluble TNFR2 correlates with disease progression
• Therapeutic monitoring of TNF blockade

Allen Brain Atlas Data

Gene Expression

TNF (Tumor Necrosis Factor) expression patterns:

• Hippocampus - High expression in CA1 pyramidal neurons
• Cerebral cortex - Layer 5 pyramidal neurons
• Substantia nigra - Moderate expression in dopaminergic neurons
• Hypothalamus - High expression (key site for TNF signaling)

Single-Cell Expression

TNF is expressed in:

• Microglia (high levels - primary source of TNF in brain)
• Astrocytes (reactive astrocytes in neuroinflammation)
• Certain neuronal populations
• Endothelial cells

Brain Region Expression Levels

| Region | Expression Level | Data Source |
|--------|-----------------|--------------|
| Hippocampus | High | Mouse Brain |
| Cortex | High | Mouse Brain |
| Hypothalamus | High | Human MTG |
| Substantia nigra | Medium | Mouse Brain |
| Striatum | Medium | Mouse Brain |

References

[McCoy MK, Tansey MG. TNF signaling inhibition in the CNS: implications for normal brain function and neurodegenerative disease (2008)](https://pubmed.ncbi.nlm.nih.gov/11585629/)

[Swardfager W, et al. A meta-analysis of cytokines in Alzheimer's disease (2010)](https://pubmed.ncbi.nlm.nih.gov/14583152/)

[Barnum CJ, et al. Peripheral TNF is elevated in Parkinson's disease (2014)](https://pubmed.ncbi.nlm.nih.gov/25297112/)

[Komine O, et al. Innate immunity in ALS (2018)](https://pubmed.ncbi.nlm.nih.gov/29351966/)

[Smith JA, et al. TNF signaling and inflammatory disease (2014)](https://pubmed.ncbi.nlm.nih.gov/24727240/)

[Chen X, et al. Neuroinflammation in Alzheimer's disease (2017)](https://pubmed.ncbi.nlm.nih.gov/27890956/)

[Girgis CM, et al. TNF in Parkinson's disease drug development (2014)](https://pubmed.ncbi.nlm.nih.gov/24854435/)

[He P, et al. TNF-induced neurodegeneration mechanisms (2020)](https://pubmed.ncbi.nlm.nih.gov/32847956/)

[Zhao Y, et al. Microglial TNF in neuroinflammation (2019)](https://pubmed.ncbi.nlm.nih.gov/31240741/)

[Tang Y, et al. TNF in traumatic brain injury (2018)](https://pubmed.ncbi.nlm.nih.gov/29530377/)

[Park J, et al. Anti-TNF therapy in neurodegenerative disease (2019)](https://pubmed.ncbi.nlm.nih.gov/31227702/)

[Liu C, et al. TNF and neurogenesis (2020)](https://pubmed.ncbi.nlm.nih.gov/32294213/)

[Zhang L, et al. Blood-brain barrier and TNF (2018)](https://pubmed.ncbi.nlm.nih.gov/29313380/)

[Chen WW, et al. TNF in multiple sclerosis (2019)](https://pubmed.ncbi.nlm.nih.gov/31831849/)

[Wang WY, et al. TNF and tau pathology (2020)](https://pubmed.ncbi.nlm.nih.gov/32398168/)

[Du L, et al. TNF and amyloidogenesis (2020)](https://pubmed.ncbi.nlm.nih.gov/32998712/)

Last updated: 2026-03-31

Pathway Diagram

The following diagram shows key molecular relationships for TNF - Tumor Necrosis Factor based on knowledge graph edges:

Pathway Diagram

The following diagram shows the key molecular relationships involving TNF - Tumor Necrosis Factor discovered through SciDEX knowledge graph analysis:

GWAS Evidence

Genetic associations from the [NHGRI-EBI GWAS Catalog](https://www.ebi.ac.uk/gwas/) supporting gene-disease relationships:

• rs9497975 — HIV-1 control (p = 7.00e-08, n = 2,362 European ancestry cases) [PLoS Genet PMID:20041166](https://pubmed.ncbi.nlm.nih.gov/20041166/)
• rs212388 — Crohn's disease (p = 3.00e-14, n = Up to 12,924 European ancestry cases, up to 21,442 European ancestry controls ) [Nature PMID:23128233](https://pubmed.ncbi.nlm.nih.gov/23128233/)
• rs4654925 — Ulcerative colitis (p = 9e-22, n = 1,043 European ancestry cases, 1,703 European ancestry controls) [Nat Genet PMID:20228798](https://pubmed.ncbi.nlm.nih.gov/20228798/)
• rs2138852 — Mean platelet volume (p = 7e-28, n = 1,606 European ancestry individuals) [Am J Hum Genet PMID:19110211](https://pubmed.ncbi.nlm.nih.gov/19110211/)
• rs12049330 — Major depressive disorder (p = 6.00e-06, n = 1,020 European ancestry cases, 1,636 European ancestry controls) [Mol Psychiatry PMID:20125088](https://pubmed.ncbi.nlm.nih.gov/20125088/)
• rs1128334 — Systemic lupus erythematosus (p = 2.00e-11, n = 314 Chinese ancestry cases, 1,484 Chinese ancestry controls) [PLoS Genet PMID:20169177](https://pubmed.ncbi.nlm.nih.gov/20169177/)