Table 2.
Immunological Protein Functions
| Abbreviation | Full Name | Function in Relation to Viral Immunitya |
|---|---|---|
| MAVS | Mitochondrial Antiviral Signaling Protein | Required for innate immune defense against viruses, acts downstream of innate immune proteins that detect intracellular dsRNA produced during viral replication, leads to activation of NFκB, IRF3, and IRF7 and to subsequent induction of antiviral cytokines. |
| TBK1 | TANK Binding Kinase 1 | Serine/threonine kinase that plays an essential role in regulating inflammatory responses to viruses. Following activation of toll-like receptors by viral components, TBK1 associates with TRAF3 and TANK and phosphorylates IRF3 and IRF7. |
| NFκB | Nuclear Factor Kappa B | NFκB is a major transcription factor that regulates genes responsible for both the innate and adaptive immune response to viral infections. Activation of NFκB results in systemic inflammation. |
| IFIH1/MDA5 | Interferon Induced With Helicase C Domain 1/Melanoma Differentiation-Associated Protein 5 | Innate immune receptor that acts as a cytoplasmic sensor of viral nucleic acids and plays a major role in sensing viral infection and in the activation of a cascade of antiviral responses, including the induction of type I interferons and pro-inflammatory cytokines. |
| IRF3 and IRF7 | Interferon Regulatory Factor 3 and 7 | Key transcriptional regulators of type I IFN-dependent immune responses and plays a critical role in the innate immune response against DNA and RNA viruses. Regulates the transcription of type I IFN genes (IFN-alpha and IFN-beta) and ISG by binding to an ISRE in their promoters. IRF3 acts as a more potent activator of the IFN-beta gene than the IFN-alpha gene, IRF7 can efficiently activate both the IFN-beta and the IFN-alpha genes. |
| STAT1 | Signal Transducer And Activator Of Transcription 1 | Signal transducer and activator of transcription that mediates signaling by type I, II, and III IFNs |
| STAT2 | Signal Transducer And Activator Of Transcription 2 | Signal transducer and activator of transcription that mediates signaling by type I IFNs and type III IFNs |
| IFNAR | Interferon Alpha/Beta Receptor Subunit 1 | Component of the receptor for type I interferons, a heterodimer with IFNAR2. Activation leads to downstream STAT proteins, ISGs, as well as type I IFN themselves. |
| IL28RA | IL-28 Receptor Subunit Alpha | The IL28RA/IL10RB dimer is a receptor for type III IFNs, IFN-lambda 2 and IFN-lambda 3 and mediates their antiviral activity. |
| IFNGR | Interferon gamma receptor | Heterodimer of IFNGR1 and IFNGR2, the receptor for type II IFN (IFNγ) |
| Type I IFNs | Type I Interferons | IFN-alpha (IFNα), IFN-beta (IFNβ) |
| Type III IFNs | Type III Interferons | IFN-lambda (IFNλ) |
| IL-2 | Interleukin 2 | Produced by T-cells in response to antigenic or mitogenic stimulation, required for T-cell proliferation and other activities crucial to regulation of the immune response. |
| IL-6 | Interleukin 6 | Produced by macrophages and endothelia cells in response to tissues damage and acts as a potent inducer of the acute immune response. Plays an essential role in the final differentiation of B-cells into Ab-secreting cells and involved in lymphocyte and monocyte differentiation. |
| IL-7 | Interleukin 7 | An important growth factor for T- and B-cell development and maturation. |
| IL-8 | Interleukin 8 | A chemotactic factor that attracts neutrophils, basophils, and T cells, but not monocytes. |
| IL-10 | Interleukin 10 | Major immune regulatory cytokine that has anti-inflammatory functions, limiting excessive tissue disruption caused by inflammation. Mainly produced by monocytes and to a lesser extent by lymphocytes. |
| IL-18 | Interleukin 18 | A proinflammatory cytokine primarily produced by macrophages as a result of inflammasome activation. |
| IL-1β | Interleukin 1 beta | A proinflammatory cytokine primarily produced by macrophages as a result of inflammasome activation. |
| IFNγ | Interferon gamma | Produced by lymphocytes activated by specific antigens or mitogens, has antiviral activity, and is a potent activator of macrophages. |
| G-CSF/CSF3 | Granulocyte Colony-Stimulating Factor | Granulocyte/macrophage colony-stimulating factors are cytokines that act in hematopoiesis by controlling the production, differentiation, and function of 2 related white cell populations of the blood, the granulocytes and the monocytes-macrophages. |
| MCP-1/CCL2 | Monocyte Chemotactic Protein 1 | Chemokine that exhibits a chemotactic activity for monocytes and basophils but not neutrophils or eosinophils. |
| IP-10/CXCL10 | Interferon-Inducible Protein 10 | Chemokine that plays an important role during viral infections by stimulating the activation and migration of immune cells to the site of infection. |
| MIP-1α/CCL3 | Macrophage Inflammatory Protein 1α | Monokine with inflammatory and chemokinetic properties. |
| TNF | Tumor Necrosis Factor | Cytokine mainly secreted by macrophages, which is a potent pyrogen causing fever by direct action or by stimulation of interleukin-1. |
| GM-CSF/CSF2 | Granulocyte-macrophage colony-stimulating factor | Cytokine that stimulates the growth and differentiation of hematopoietic precursor cells from various lineages, including granulocytes, macrophages, eosinophils and erythrocytes. |
| ACE2 | Angiotensin I Converting Enzyme 2 | The organ- and cell-specific expression of this gene suggests that it may play a role in the regulation of cardiovascular, renal and lung function, as well as fertility. The encoded protein is a functional receptor for the spike glycoprotein of the human coronavirus HCoV-NL63 and the human severe acute respiratory syndrome coronaviruses, SARS-CoV and SARS-CoV-2 (COVID-19 virus). |
aFunctional descriptions adapted from https://www.genecards.org/.
TRAF3=TNF Receptor Associated Factor 3; ISG= interferon stimulated gene; ISRE= Interferon-sensitive response element.